DR ANTHONY MELVIN CRASTO Ph.D

DR ANTHONY MELVIN CRASTO, Worlddrugtracker, Born in Mumbai in 1964 and graduated from Mumbai University, Completed his PhD from ICT ,1991, Mumbai, India, in Organic chemistry, The thesis topic was Synthesis of Novel Pyrethroid Analogues, Currently he is working with AFRICURE PHARMA as ADVISOR earlier GLENMARK LS Research centre as consultant,Principal Scientist, Process Research (bulk actives) at Mahape, Navi Mumbai, India. Prior to joining Glenmark, he worked with major multinationals like Hoechst Marion Roussel, now sSanofi, Searle India ltd, now Rpg lifesciences, etc. he is now helping millions, has million hits on google on all organic chemistry websites. His New Drug Approvals, Green Chemistry International, Eurekamoments in organic chemistry are some most read blogs He has hands on experience in initiation and developing novel routes for drug molecules and implementation them on commercial scale over a 32 year tenure, good knowledge of IPM, GMP, Regulatory aspects, he has several international drug patents published worldwide . He gas good proficiency in Technology transfer, Spectroscopy, Stereochemistry, Synthesis, polymorphism etc He suffered a paralytic stroke in dec 2007 and is bound to a wheelchair, this seems to have injected feul in him to help chemists around the world, he is more active than before and is pushing boundaries, he has one lakh connections on all networking sites, He makes himself available to all, contact him on +91 9323115463, amcrasto@gmail.com

Difelikefalin

Phase 3 drug Comments Off

May 302016

Difelikefalin, CR-845; MR-13A-9; MR-13A9

4-amino-1- (D-phenylalanyl-D-phenylalanyl-D-leucyl-D-lysyl) piperidine-4-carboxylic acid

C36H53N7O6, 679.40573

Originator	Ferring Pharmaceuticals
Developer	Cara Therapeutics
Class	Analgesic drugs (peptides)
Mechanism Of Action	Opioid kappa receptor agonists
Who Atc Codes	D04A-X (Other antipruritics), N02A (Opioids)
Ephmra Codes	D4A (Anti-Pruritics, Including Topical Antihistamines, Anaesthetics, etc), N2A (Narcotics)
Indication	Pain, Osteoarthritis, Pruritus

A kappa opioid receptor agonist potentially for treatment of post-operative pain and uremic pruritus.

Difelikefalin, also known CR845, is a novel and potent kappa opioid receptor agonist. CR845 exhibit low P450 CYP inhibition and low penetration into the brain. CR845 may be useful in the prophylaxis and treatment of pain and inflammation associated with a variety of diseases and conditions .

No. CAS 1024828-77-0

2D chemical structure of 1024828-77-0

Difelikefalin ( INN ) (Developmental Code Names CR845 , FE-202845 ), Also Known As D -Phe- D -Phe- D -Leu- D -Lys- [Ganma- (4-N-Piperidinyl) Amino Carboxylic Acid] (As The Acetate Salt ), Is An Analgesic Opioid Peptide ^[2] Acting As A Peripherally-Specific , Highly Selective Agonist Of The kappa-Opioid Receptor (KOR). ^[1]^[3]^[4]^[5] It Is Under Development By Cara Therapeutics As An Intravenous Agent For The Treatment Of Postoperative Pain . ^[1]^[3]^[5] An Oral Formulation Has Also Been Developed. ^[5] Due To Its Peripheral Selectivity, Difelikefalin Lacks The Central Side Effects Like Sedation , Dysphoria , And Hallucinations Of Previous KOR-Acting Analgesics Such As Pentazocine And Phenazocine . ^[1]^[3] In Addition To Use As An Analgesic, Difelikefalin Is Also Being Investigated For The Treatment Of Pruritus (Itching). ^[1]^[3]^{[4 ]} Difelikefalin Has Completed Phase II Clinical Trials For Postoperative Pain And Has Demonstrated Significant And “Robust” Clinical Efficacy, Along With Being Safe And Well-Tolerated. ^[3]^[5] It Is Also In Phase II Clinical Trials For Uremic Pruritus In Hemodialysis Patients. ^[4]

Difelikefalin Acts As An Analgesic By Activating KORs On Peripheral Nerve Terminals And KORs Expressed By Certain Immune System Cells . ^[1] Activation Of KORs On Peripheral Nerve Terminals Results In The Inhibition Of Ion Channels Responsible For Afferent Nerve Activity , Causing Reduced Transmission Of Pain Signals , While Activation Of KORs Expressed By Immune System Cells Results In Reduced Release Of Proinflammatory , Nerve-Sensitizing Mediators (Eg, Prostaglandins ). ^[1]

PATENT

WO 2015198505

κ opioid receptor agonists are known to be useful as therapeutic agents for various pain. Among, kappa opioid receptor agonist with high selectivity for peripheral kappa opioid receptors, are expected as a medicament which does not cause the central side effects. Such as peripherally selective κ opioid receptor agonist, a synthetic pentapeptide has been reported (Patent Documents 1 and 2).

　The following formula among the synthetic pentapeptide (A)

[Formula 1] Being Represented By Compounds Are Useful As Pain Therapeutics. The Preparation Of This Compound, Solid Phase Peptide Synthesis Methods In Patent Documents 1 And 2 Have Been Described.

Document 1 Patent: Kohyo 2010-510966 JP
Patent Document 2: Japanese Unexamined Patent Publication No. 2013-241447

　Compound (1) or a salt thereof and compound (A), for example as shown in the following reaction formula, 4-aminopiperidine-4-carboxylic acid, D- lysine (D-Lys), D- leucine (D-Leu) , it can be prepared by D- phenylalanine (D-Phe) and D- phenylalanine (D-Phe) sequentially solution phase peptide synthesis methods condensation.

[Of 4]

The present invention will next to examples will be described in further detail.

Example
1 (1) Synthesis of Cbz-D-Lys (Boc) -α-Boc-Pic-OMe (3)
to the four-necked flask of 2L, α-Boc-Pic- OMe · HCl [α-Boc-4 – aminopiperidine-4-carboxylic acid methyl hydrochloride] were charged (2) 43.7g (148mmol), was suspended in EtOAc 656mL (15v / w). To the suspension of 1-hydroxybenzotriazole (HOBt) 27.2g (178mmol), while cooling with Cbz-D-Lys (Boc) -OH 59.2g (156mmol) was added an ice-bath 1-ethyl -3 – (3-dimethylcarbamoyl amino propyl) was added to the carbodiimide · HCl (EDC · HCl) 34.1g (178mmol). After 20 minutes, stirring was heated 12 hours at room temperature. After completion of the reaction, it was added and the organic layer was 1 N HCl 218 mL of (5.0v / w). NaHCO to the resulting organic layer ₃ Aq. 218ML (5.0V / W), Et ₃ N 33.0 g of (326Mmol) was stirred for 30 minutes, and the mixture was separated. The organic layer HCl 218ML 1N (5.0V / W), NaHCO ₃ Aq. 218mL (5.0v / w), NaClaq . Was washed successively with 218ML (5.0V / W), Na ₂ SO ₄　dried addition of 8.74g (0.2w / w). Subjected to vacuum filtration, was concentrated under reduced pressure resulting filtrate by an evaporator, and pump up in the vacuum pump, the Cbz-D-Lys (Boc) -α-Boc-Pic-OMe (3) 88.9g as a white solid obtained (96.5% yield, HPLC purity 96.5%).

[0033]

(2) D-Lys (Boc) Synthesis Of -Arufa-Boc-Pic-OMe (4)
In An Eggplant-Shaped Flask Of 2L, Cbz-D-Lys (Boc) -Arufa-Boc-Pic-OMe (3) 88.3g (142mmol) were charged, it was added and dissolved 441mL (5.0v / w) the EtOAc. The 5% Pd / C to the reaction solution 17.7g (0.2w / w) was added, After three nitrogen substitution reduced pressure Atmosphere, Was Performed Three Times A Hydrogen Substituent. The Reaction Solution Was 18 Hours With Vigorous Stirring At Room Temperature To Remove The Pd / C And After The Completion Of The Reaction Vacuum Filtration. NaHCO The Resulting Filtrate ₃ Aq. 441ML And (5.0V / W) Were Added For Liquid Separation, And The Organic Layer Was Extracted By The Addition Of EtOAc 200ML (2.3V / W) In The Aqueous Layer. NaHCO The Combined Organic Layer ₃ Aq. 441ML And (5.0V / W) Were Added for liquid separation, and the organic layer was extracted addition of EtOAc 200mL (2.3v / w) in the aqueous layer. NaClaq the combined organic layers. 441mL and (5.0v / w) is added to liquid separation, was extracted by the addition EtOAc 200ML Of (2.3V / W) In The Aqueous Layer. The Combined Organic Layer On The Na ₂ SO ₄　Dried Addition Of 17.7 g of (0.2W / W), Then The Filtrate Was Concentrated Under Reduced Pressure Obtained Subjected To Vacuum Filtration By an evaporator, and pump up in the vacuum pump, D-Lys (Boc) -α-Boc-Pic- OMe (4) to give 62.7g (90.5% yield, HPLC purity 93.6%).

(3) Cbz-D-Leu -D-Lys (Boc) -α-Boc-Pic-OMe synthesis of (5)
in the four-necked flask of 2L, D-Lys (Boc) -α-Boc-Pic-OMe (4) was charged 57.7 g (120 mmol), was suspended in EtOAc 576mL (10v / w). HOBt 19.3g (126mmol) to this suspension, was added EDC · HCl 24.2g (126mmol) while cooling in an ice bath added Cbz-D-Leu-OH 33.4g (126mmol). After 20 minutes, after stirring the temperature was raised 5 hours at room temperature, further the EDC · HCl and stirred 1.15 g (6.00 mmol) was added 16 h. After completion of the reaction, it was added liquid separation 1N HCl 576mL (10v / w) . NaHCO to the resulting organic layer ₃ Aq. 576ML (10V / W), Et ₃ N 24.3 g of (240Mmol) was stirred for 30 minutes, and the mixture was separated. The organic layer HCl 576ML 1N (10V / W), NaHCO ₃ Aq. 576mL (10v / w), NaClaq . Was washed successively with 576ML (10V / W), Na ₂ SO ₄　dried addition of 11.5g (0.2w / w). After the filtrate was concentrated under reduced pressure obtained subjected to vacuum filtration by an evaporator, and pump up in the vacuum pump, the Cbz-D-Leu-D- Lys (Boc) -α-Boc-Pic-OMe (5) 85.8g It was obtained as a white solid (98.7% yield, HPLC purity 96.9%).

(4) D-Leu-D -Lys (Boc) -α-Boc-Pic-OMe synthesis of (6)
in an eggplant-shaped flask of 1L, Cbz-D-Leu- D-Lys (Boc) -α-Boc-Pic -OMe the (5) 91.9g (125mmol) were charged, was added and dissolved 459mL (5.0v / w) the EtOAc. The 5% Pd / C to the reaction solution 18.4g (0.2w / w) was added, After three nitrogen substitution reduced pressure atmosphere, was performed three times a hydrogen substituent. The reaction solution was subjected to 8 hours with vigorous stirring at room temperature to remove the Pd / C and after the completion of the reaction vacuum filtration. NaHCO the resulting filtrate ₃ Aq. 200mL (2.2v / w) were added to separate liquid, NaHCO to the organic layer ₃ Aq. 200mL (2.2v / w), NaClaq . It was sequentially added washed 200mL (2.2v / w). To the resulting organic layer Na ₂ SO ₄　dried added 18.4g (0.2w / w), to the filtrate concentrated under reduced pressure obtained subjected to vacuum filtration by an evaporator, and a pump-up with a vacuum pump. The resulting amorphous solid was dissolved adding EtOAc 200mL (2.2v / w), was crystallized by the addition of heptane 50mL (1.8v / w). Was filtered off precipitated crystals by vacuum filtration, the crystals were washed with a mixed solvent of EtOAc 120mL (1.3v / w), heptane 50mL (0.3v / w). The resulting crystal 46.1g to added to and dissolved EtOAc 480mL (5.2v / w), was crystallized added to the cyclohexane 660mL (7.2v / w). Was filtered off under reduced pressure filtered to precipitate crystals, cyclohexane 120mL (1.3v / w), and washed with a mixed solvent of EtOAc 20mL (0.2v / w), and 30 ° C. vacuum dried, D-Leu- as a white solid D-Lys (Boc) -α- Boc-Pic-OMe (6) to give 36.6 g (48.7% yield, HPLC purity 99.9%).

(5) Synthesis of Cbz-D-Phe-D- Leu-D-Lys (Boc) -α-Boc-Pic-OMe (7)
to the four-necked flask of 1L, D-Leu-D- Lys (Boc) -α-Boc-Pic-OMe with (6) 35.8g (59.6mmol) was charged, it was suspended in EtOAc 358mL (10v / w). To this suspension HOBt 9.59g (62.6mmol), Cbz- D-Phe-OH 18.7g was cooled in an ice bath is added (62.6mmol) while EDC · HCl 12.0g (62.6mmol) It was added. After 20 minutes, a further EDC · HCl After stirring the temperature was raised 16 hours was added 3.09 g (16.1 mmol) to room temperature. After completion of the reaction, it was added and the organic layer was 1N HCl 358mL of (10v / w). NaHCO to the resulting organic layer ₃ Aq. 358ML (10V / W), Et ₃ N 12.1 g of (119Mmol) was stirred for 30 minutes, and the mixture was separated. The organic layer HCl 358ML 1N (10V / W), NaHCO ₃ Aq. 358mL (10v / w), NaClaq . Was washed successively with 358ML (10V / W), Na ₂ SO ₄　dried addition of 7.16g (0.2w / w). After the filtrate was concentrated under reduced pressure obtained subjected to vacuum filtration by an evaporator, and pump up in the vacuum pump, Cbz-D-Phe-D -Leu-D-Lys (Boc) -α-Boc-Pic-OMe (7) was obtained 52.5g as a white solid (yield quant, HPLC purity 97.6%).

(6) D-Phe-D -Leu-D-Lys (Boc) synthesis of -α-Boc-Pic-OMe ( 8)
in an eggplant-shaped flask of 2L, Cbz-D-Phe- D-Leu-D-Lys ( Boc) -α-Boc-Pic- OMe (7) the 46.9g (53.3mmol) were charged, the 840ML EtOAc (18V / W), H ₂ added to and dissolved O 93.8mL (2.0v / w) It was. The 5% Pd / C to the reaction mixture 9.38g (0.2w / w) was added, After three nitrogen substitution reduced pressure atmosphere, was performed three times a hydrogen substituent. The reaction solution was subjected to 10 hours with vigorous stirring at room temperature to remove the Pd / C and after the completion of the reaction vacuum filtration. NaHCO the resulting filtrate ₃ Aq. 235mL (5.0v / w) were added to separate liquid, NaHCO to the organic layer ₃ Aq. 235mL (5.0v / w), NaClaq . It was added sequentially cleaning 235mL (5.0v / w). To the resulting organic layer Na ₂ SO ₄　dried addition of 9.38g (0.2w / w), then the filtrate was concentrated under reduced pressure obtained subjected to vacuum filtration by an evaporator, pump up with a vacuum pump to D-Phe -D-Leu-D-Lys ( Boc) -α-Boc-Pic-OMe (7) was obtained 39.7g (yield quant, HPLC purity 97.3%).

351mL was suspended in (10v / w). To this suspension HOBt 7.92g (51.7mmol), Boc-D-Phe-OH HCl HCl

(8) D-Phe-D -Phe-D-Leu-D-Lys-Pic-OMe Synthesis Of Hydrochloric Acid Salt (1)
In An Eggplant-Shaped Flask Of 20ML Boc-D-Phe-D -Phe-D- Leu-D- lys (Boc) -α -Boc- Pic-OMe (9) and 2.00gg, IPA 3.3mL (1.65v / w), was suspended by addition of PhMe 10mL (5v / w). It was stirred at room temperature for 19 hours by addition of 6N HCl / IPA 6.7mL (3.35v / w). The precipitated solid was filtered off by vacuum filtration and dried under reduced pressure to a white solid of D-Phe-D-Phe- D- Leu-D-Lys-Pic- OMe 1.59ghydrochloride (1) (yield: 99 .0%, HPLC purity 98.2%) was obtained.

(9) D-Phe-D -Phe-D-Leu-D-Lys-Pic-OMe Purification Of The Hydrochloric Acid Salt (1)
In An Eggplant-Shaped Flask Of 20ML-D-Phe-D- Phe D-Leu -D-Lys- pic-OMe hydrochloride crude crystals (1) were charged 200mg, EtOH: MeCN = 1: after stirring for 1 hour then heated in a mixed solvent 4.0 mL (20v / w) was added 40 ° C. of 5 , further at room temperature for 2 was time stirring slurry. Was filtered off by vacuum filtration, the resulting solid was dried under reduced pressure a white solid ((1) Purification crystals) was obtained 161 mg (80% yield, HPLC purity 99.2% ).

(10) D-Phe-D -Phe-D-Leu-D-Lys-Pic Synthesis (Using Purified
(1)) Of (A) To A Round-Bottomed Flask Of 10ML D-Phe-D-Phe-D- -D-Lys Leu-Pic-OMe Hydrochloride Salt (1) Was Charged With Purified Crystal 38.5Mg (0.0488Mmol), H ₂ Was Added And Dissolved O 0.2ML (5.2V / W). 1.5H Was Stirred Dropwise 1N NaOH 197MyuL (0.197mmol) at room temperature. After completion of the reaction, concentrated under reduced pressure by an evaporator added 1N HCl 48.8μL (0.0488mmol), to obtain a D-Phe-D-Phe- D-Leu-D-Lys- Pic (A) (yield: quant , HPLC purity 99.7%).

D-Phe-D-Phe- D-Leu-D-Lys-Pic-OMe (1) physical properties ¹ H NMR (400 MHz, 1M DCl) [delta] ppm by: 0.85-1.02 (yd,. 6 H), 1.34-1.63 ( m, 5 H), 1.65-2.12 ( m, 5 H), 2.23-2.45 (m, 2 H), 2.96-3.12 (m, 4 H), 3.19 (ddt, J = 5.0 & 5.0 & 10.0 Hz), 3.33-3.62 (m, 1 H), 3.68-3.82 (m, 1 H), 3.82-3.95 (m, 4 H), 3.95-4.18 (m, 1 H), 4.25-4.37 (m, 2 H), 4.61-4.77 (M, 2 H), 7.21-7.44 (M, 10 H) ¹³ C NMR (400MHz, 1M DCl) Deruta Ppm: 21.8, 22.5, 24.8, 27.0, 30.5, 30.8, 31.0, 31.2, 31.7, 37.2 , 37.8, 38.4, 39.0, 39.8, 40.4, 40.6, 41.8, 42.3, 49.8, 50.2, 52.2, 52.6, 54.6, 55.2, 57.7, 57.9, 127.6, 128.4, 129.2, 129.6, 129.7, 129.8 dp 209.5 ℃

Example 2
(Trifluoroacetic Acid (TFA)
Use) (1) D-Phe-D-Phe-D-Leu-D-Lys-Pic-OMe TFA Synthesis Of Salt (1)
TFA 18ML Eggplant Flask Of 50ML (18V / W) , 1- Dodecanethiol 1.6ML (1.6V / W), Triisopropylsilane 0.2ML (0.2V / W), H ₂ Sequentially Added Stirring The O 0.2ML (0.2V / W) Did. The Solution To The Boc-D-Phe- D- Phe-D-Leu-D -Lys (Boc) -α-Boc-Pic-OMe the (9) 1.00g (1.01mmol) was added in small portions with a spatula. After completion of the reaction, concentrated under reduced pressure by an evaporator, it was added dropwise the resulting residue in IPE 20mL (20v / w). The precipitated solid was filtered off, the resulting solid was obtained and dried under reduced pressure to D-Phe-D-Phe- D-Leu -D-Lys-Pic-OMe · TFA salt as a white solid (1) (Osamu rate 93.0%, HPLC purity 95.2%).

(2) D-Phe-D -Phe-D-Leu-D-Lys-Pic synthesis of (A)
to a round-bottomed flask of 10mL D-Phe-D-Phe -D-Leu-D-Lys-Pic-OMe TFA were charged salt (1) 83mg (0.0843mmol), was added and dissolved H2O 431μL (5.2v / w). Was 12h stirring dropwise 1N NaOH 345μL (0.345mmol) at room temperature. After completion of the reaction, concentrated under reduced pressure by an evaporator added 1N HCl 84.3μL (0.0843mmol), to obtain a D-Phe-D-Phe- D-Leu-D-Lys-Pic (A) ( yield: quant, HPLC purity 95.4%).

Example
3 (HCl / EtOAc
Use) (1) In An Eggplant-Shaped Flask Of 30ML Boc-D-Phe-D -Phe-D-Leu-D-Lys (Boc) -Arufa-Boc-Pic-OMe (9) 1. It was charged with 00g (1.01mmol ), was added and dissolved EtOAc7.0mL (7.0v / w). 4N HCl / EtOAc 5.0mL (5.0v / w) was added after 24h stirring at room temperature, the precipitated solid was filtered off by vacuum filtration, washed with EtOAc 2mL (2.0v / w). The resulting solid D-Phe-D-Phe- D-Leu-D-Lys-Pic-OMe hydrochloride (1) was obtained 781mg of a white solid was dried under reduced pressure (the 96.7% yield, HPLC purity 95.4%).

(2) D-Phe-D -Phe-D-Leu-D-Lys-Pic (A) Synthesis of
eggplant flask of 10mL D-Phe-D-Phe -D-Leu-D-Lys-Pic-OMe hydrochloride were charged salt (1) 90 mg (0.112 mmol), H ₂ was added and dissolved O 0.47mL (5.2v / w). Was 12h stirring dropwise 1N NaOH 459μL (0.459mmol) at room temperature. After completion of the reaction, concentrated under reduced pressure by an evaporator added 1N HCl 0.112μL (0.112mmol), was obtained D-Phe-D-Phe- D-Leu-D-Lys-Pic (A) ( yield: quant, HPLC purity 93.1%).

4 Example
Compound (1) Of The Compound By Hydrolysis Synthesis Of (The A) (Compound (1) Without
Purification) Eggplant Flask 10ML D-Phe-D-Phe -D-Leu-D-Lys-Pic-OMe (1) Charged Hydrochloride Were (Without Pre-Step Purification) 114.5Mg (0.142Mmol), H ₂ Was Added And Dissolved O 595MyuL (5.2V / W). Was 14H Stirring Dropwise 1N NaOH 586MyuL (0.586Mmol) At Room Temperature. After Completion Of the reaction, concentrated under reduced pressure by an evaporator added 1N HCl 0.15μL (0.150mmol), was obtained D-Phe-D-Phe- D-Leu-D-Lys-Pic (A) (yield: quant, HPLC purity 95.2 %).

Example 1 Comparative
Path Not Via The Compound (1) (Using Whole Guard Boc-D-Phe-D-Phe-D-Leu-D-Lys (Boc) -Alpha-Boc-Pic-OMe
(A)) (1) D–Boc Phe- D-Phe-D-Leu-D-Lys (Boc) -Arufa-Boc-Pic-OH Synthesis Of
Eggplant Flask Of 30ML Boc-D-Phe-D -Phe-D-Leu-D- Lys (Boc) -α- Boc-Pic -OMe (9) were charged 1.00g (1.00mmol), was added and dissolved MeOH 5.0mL (5.0v / w). After stirring for four days by the addition of 1N NaOH 1.1 mL (1.10mmol) at room temperature, further MeOH 5.0mL (5.0v / w), 1N NaOH 2.0mL the (2.0mmol) at 35 ℃ in addition 3h and the mixture was stirred. After completion of the reaction, 1 N HCl 6.1 mL was added, After distilling off the solvent was concentrated under reduced pressure was separated and the organic layer was added EtOAc 5.0mL (5.0mL) .NaClaq. 5.0mL (5.0v / w) Wash the organic layer was added, the organic layer as a white solid was concentrated under reduced pressure to Boc-D-Phe-D- Phe-D-Leu-D-Lys (Boc) – α-Boc-Pic-OH 975.1mg (99.3% yield, HPLC purity 80.8% )

(2) D-Phe-D -Phe-D-Leu-D-Lys-Pic synthesis of (A)
to a round-bottomed flask of 20mL Boc-D-Phe-D -Phe-D-Leu-D-Lys (Boc) It was charged -α-Boc-Pic-OH ( 10) 959mg (0.978mmol), was added and dissolved EtOAc 4.9mL (5.0v / w). And 4h stirring at room temperature was added dropwise 4N HCl / EtOAc 4.9mL (5.0mL) at room temperature. After completion of the reaction, it was filtered under reduced pressure, a white solid as to give D-Phe-D-Phe- D-Leu-D-Lys-Pic the (A) (96.4% yield, HPLC purity 79.2%) .

　If not via the compound of the present invention (1), the purity of the compound obtained (A) was less than 80%.

PATENT

http://www.google.com/patents/US20110212882

References

S. Sinatra Raymond; Jonathan S. Jahr;. J. Michael Watkins-Pitchford (14 October 2010) The Essence Of Analgesia And Analgesics …. Cambridge University Press Pp 490-491 ISBN 978-1-139-49198-3 .
A Janecka, Perlikowska R, Gach K, Wyrebska A, Fichna J (2010) “Development Of Opioid Peptide Analogs For Pain Relief”.. Curr Pharm Des… 16 (9):. 1126-35 Doi : 10.2174 / 138161210790963869 . PMID 20030621 .
Apfelbaum Jeffrey (8 September 2014). Ambulatory Anesthesia, An Issue Of Anesthesiology Clinics, . Elsevier Health Sciences. Pp. 190-. ISBN 978-0-323-29934-3 .
Cowan Alan;. Gil Yosipovitch (10 April 2015) Pharmacology Of Itch …. Springer Pp 307- ISBN 978-3-662-44605-8 .
Allerton Charlotte (2013). Pain Therapeutics: Current And Future Treatment Paradigms …. Royal Society Of Chemistry Pp 56- ISBN 978-1-84973-645-9 .

REFERENCES

1: Cowan A, Kehner GB, Inan S. Targeting Itch With Ligands Selective For kappa Opioid
. Receptors Handb Exp Pharmacol 2015; 226:.. 291-314 Doi:
.. 10.1007 / 978-3-662-44605-8_16 Review PubMed PMID: 25861786.

Difelikefalin
Systematic (IUPAC) Name

Amino–4 1- ( D -Phenylalanyl- D -Phenylalanyl- D -Leucyl- D -Lysyl) Piperidine-4-Carboxylic Acid
Clinical data
Of Routes Administration	Intravenous
Pharmacokinetic Data
Bioavailability	Pasento 100 ( IV ) ^[1]
Metabolism	Metabolized Not ^[1]
Biological half-life	Hours 2 ^[1]
Excretion	As Unchanged Excreted Drug Via Bile And Urine ^[1]
Identifiers
CAS Number	1024828-77-0
ATC code	None
ChemSpider	44208824
Chemical data
Formula	C ₃₆H ₅₃N ₇O ₆
Molar mass	679.85 g / mol

///// Difelikefalin, CR845 , FE-202845,

CC (C) C [C @ H] (C (= O) N [C @ H] (CCCCN) C (= O) N1CCC (CC1) (C (= O) O) N) NC (= O) [ C @@ H] (Cc2ccccc2) NC (= O) [C @@ H] (Cc3ccccc3) N

Rovatirelin Hydrate

Phase 3 drug Comments Off

May 302016

2D chemical structure of 204386-76-5

Rovatirelin Hydrate, S-0373,

Rovatirelin, RN: 204386-76-5
UNII: 9DL0X410PY

(4S,5S)-5-methyl-N-((2S)-1-((2R)-2-methylpyrrolidin-1-yl)-1-oxo-3-((1,3-thiazol-4-yl)methyl)propan-2-yl)-2-oxo-1,3-oxazolidine-4-carboxamide

(4S,5S)-5-methyl-N-((S)-1-((R)-2-methylpyrrolidin-1-yl)-1-oxo-4-(thiazol-4-yl)butan-2-yl)-2-oxooxazolidine-4-carboxamide4-Oxazolidinecarboxamide, 5-methyl-N-[2-(2-methyl-1-pyrrolidinyl)-2-oxo-1-(4-thiazolylmethyl)ethyl]-2-oxo-, [4S-[4α[R*(S*)],5α]]-

A thyrotropin-releasing hormone potentially for the treatment of spinocerebellar ataxia.

CAS No.204386-76-5(Rovatirelin)

879122-87-9(Rovatirelin Hydrate)

C17H24N4O4S
Exact Mass: 380.1518

Rovatirelin is a novel synthetic agent that mimics the actions of thyrotropin-releasing hormone (TRH). Rovatirelin binds to the human TRH receptor with higher affinity (Ki=702nM) than taltirelin (Ki=3877nM). Rovatirelin increased the spontaneous firing of action potentials in the acutely isolated noradrenergic neurons of rat locus coeruleus (LC). Rovatirelin increased locomotor activity. Rovatirelin may have an orally effective therapeutic potential in patients with SCD.

Rovatirelin ([1-[-[(4S,5S)-(5-methyl-2-oxo oxazolidin-4-yl) carbonyl]-3-(thiazol-4-yl)-l-alanyl]-(2R)-2-methylpyrrolidine) is a novel synthetic agent that mimics the actions of thyrotropin-releasing hormone (TRH). The aim of this study was to investigate the electrophysiological and pharmacological effects of rovatirelin on the central noradrenergic system and to compare the results with those of another TRH mimetic agent, taltirelin, which is approved for the treatment of spinocerebellar degeneration (SCD) in Japan. Rovatirelin binds to the human TRH receptor with higher affinity (Ki=702nM) than taltirelin (Ki=3877nM). Rovatirelin increased the spontaneous firing of action potentials in the acutely isolated noradrenergic neurons of rat locus coeruleus (LC). The facilitatory action of rovatirelin on the firing rate in the LC neurons was inhibited by the TRH receptor antagonist, chlordiazepoxide. Reduction of the extracellular pH increased the spontaneous firing of LC neurons and rovatirelin failed to increase the firing frequency further, indicating an involvement of acid-sensitive K+ channels in the rovatirelin action. In in vivo studies, oral administration of rovatirelin increased both c-Fos expression in the LC and extracellular levels of noradrenaline (NA) in the medial prefrontal cortex (mPFC) of rats. Furthermore, rovatirelin increased locomotor activity. The increase in NA level and locomotor activity by rovatirelin was more potent and longer acting than those by taltirelin. These results indicate that rovatirelin exerts a central nervous system (CNS)-mediated action through the central noradrenergic system, which is more potent than taltirelin. Thus, rovatirelin may have an orally effective therapeutic potential in patients with SCD.

PATENT

WO 9808867

PATENT

WO 9945000

PATENT

WO 2002017954

Example

Preparation of the compound represented by Example 1 set (IX)

The second step

Two

(First step)

Method described in the literature (Synth. Commun., 20, 3507 (1990)) synthesized N- in (tert- butoxide deer Lupo sulfonyl) one 3- (4 one-thiazolyl) one L Aranin (1, 21.79 g, 80 mmol) in Torifuruoro and the mixture was stirred acetic acid (80 ml) were added under ice-cooling for 2 hours and a half. Then stirred for 30 minutes at room temperature was added to the reaction mixture p- toluenesulfonic acid hydrate (15.22 g, 80 mmol). The reaction mixture was concentrated to dryness under reduced pressure. To remove excess Torifuruoro acetic acid by the obtained residue concentrated to dryness under reduced pressure by addition of water and methanol.Obtained obtained residue was collected by filtration crystals ether was added to precipitate the compound (2) 29.8 g (quantitative).

NMR (CD ₃ OD): 9.01 (1H, d-, J = 1.8 Hz), 7.70 (2H _; yd), 7.46 (lH, d-, J = 1.8 Hz), 7.23 (2H, yd), 4.38 (1H, dd , J = 4.8 from and 3.8 from Hz), 3.45 (2H _; yd), 2.37 (3H, s).

(Second step)

I 匕合 product (2) 38.85 g E evening Nord (200 ml) of (112.8 mmol) – in THF (600 ml) solution, diphenyl di § zone methane while 攪袢 at room temperature (39 g, 201 mmol) in small portions over 30 minutes were added. The reaction mixture was stirred for 1 hour at room temperature, Ziv E sulfonyl di § zone methane (10 g, 51.5 mmol) was added and stirred for one hour. To the reaction mixture

After decomposing the excess reagent by the addition of acetic acid (0.1 ml), it was concentrated to dryness under reduced pressure and distilled off the solvent. The resulting residue (92 g) with ether (1 L) was crystallized to give compound (3) 49.05 g (96.1%).

mp: 139-140 ° C

[A] _D = -34.7 ° (C = 1.006, CHC1 ₃₎ 23 ° C)

^ Cm IRCKB ” ¹ : 1753, 1602, 1512, 1496, 1260, 1224, 1171, 1124, 1036, 1012. NMR (CD ₃ 0D): 8.92 (1H, D, J = 2 Hz), 7.70 (2H _; M ), 7.2-7.4 (13H, m) , 6.91 (1H, s), 4.62 (1H, t, J = 5.8 Hz), 3.47 (2H, d, J = 5.8 Hz), 2.36 (3H, s).

Elemental analysis (C _2E H _2S N ₂ 0 ₅ S ₂ )

Calculated: C, 61.16; H, 5.13; N, 5.49; S, 12.56.

Measured value: C, 61.14; H, 5.32; N, 5.41; S, 12.46.

(Third step)

Cis-one L one 5-methyl-2-one O Kiso O Kisa ethylbenzthiazoline one 4-carboxylic acid 13.95 g (96.14 mmol), compound (3) 49.09 g (96.14 mmol ), N-hydroxybenzotriazole To Riazoru 2.6 g (19.23 mmol) and under ice-cooling in THF (1L) solution of Toryechiruamin 14.1 ml (lOlmmol), was added to the DCC (20.83g, 101 mmol). The cooling bath was removed after stirring for 10 minutes at the same temperature, and stirred for an additional 2 0 hours at room temperature. After removing the precipitated precipitate and the filtrate concentrated to dryness under reduced pressure an oily residue (82.7 _g was obtained). The residue was filtered off and dissolved by heating to insoluble matter in acetic acid Echiru (700 ml). The filtrate was successively washed with sodium carbonate aqueous solution and water.After the addition of methanol (20 ml) the organic layer was dried with sulfuric acid mug Neshiumu, was concentrated to a small volume under reduced pressure.Precipitated collected by filtration and acetic acid E Ji Le crystals – ether (2: 3) washing to compound with a mixture (4) 35.69 g (79.8% ) was obtained. After addition was concentrated to dryness under reduced pressure of the mother liquor, and crystallized from acetic acid E Chiru ether mixture compound (4) 2.62 g (5.9% ) was obtained.

mp: 176-177 ° C

[A] _D = -39.2 ° (C = 1.007, CHC1 ₃ , 24 ° C)

^ Cm IRiKB ¹ : 1739, 1681, 1508, 1453, 1386, 1237, 1193, 1089.

NMR (CDC1 ₃ ): 8.71 (1H, d-, J = 1.8 Hz), 8.18 (lH, d-‘J = 3.9 from Hz), 7.2-7.4 (10H _; yd), 6.82 (1H, s), 6.66 (1H, d-, J = 1.8 Hz), 5.79 (1H, s), 5.12 (1H, yd), 4.94 (lH, yd), 4.35 (1H _; dd, J = 1.8 and 4.5 from Hz), 3.40 (1H _; dd, J 5.7 and 15 = Hz), 3.29 (1H _; dd, J = 4.5 of and 15 Hz), 1.27 (3H, d-, J = 6.3 Hz).

Elemental analysis (C ₂₄ H ₂₃ N ₃ 0 ₅ S)

Calculated: C, 61.92; H, 4.98; N, 9.03; S, 6.89.

Measured value: C _! 61.95; H, 5.01; N, 8.94; S ₎ 6.62.

(Fourth step)

Compound (4) 41.24 under ice-cooling to g (88.59 mmol), and the mixture was stirred Anisoru (240ml) and To Rifuruoro acetic acid (120 ml) and the mixture for 15 minutes. And the mixture was stirred for 2 hours 3 0 minutes further room temperature after removal of the cooling bath. The reaction mixture was added to the E one ether (500 ml) to the oily residue obtained by concentrated to dryness under reduced pressure was collected by filtration and pulverized. The resulting powder is water (50 ml) – was removed by filtration methanol (300 ml) warming dissolved insoluble matter in a mixture. The filtrate was concentrated to small volume under reduced pressure, and allowed to stand at room temperature for 3 days adding a seed crystal and methanol. The precipitated crystals were obtained Shi preparative filtration compound (5) 14.89 g (56.1%). The mother liquor was concentrated to dryness under reduced pressure, to give again further compound was crystallized from methanol one ether mixture of the (5) 10.3 g (38%). mp: 214-215 ° C

[]. -4.2 ° = (C = 0.5, H ₂ 0, 22 ° C)

^ Cm IRCKB ¹ : 1753, 1707, 1655, 1548, 1529, 1409, 1343, 1264, 1236, 1102, 1092. NMR (DMS0-D6): 9.02 (1H, D, J = 1.8 Hz), 8.46 (1H, d- _; J = 3.9 from Hz), 7.74 (1H, s),

7.38 (1H, d, J = 1.8 Hz), 4.77 (1H, dq, J = 6.6 and 8.7 Hz), 4.66 (1H, m), 4.21 (1H, d,

J = 8.7 Hz), 3.24 (IH, dd, J = 5.1 and 15 Hz), 3.13 (1H, dd, J = 8.4 and 15 Hz),

1.13 (3H, d, J = 6.6 Hz).

Elemental analysis (C _U H ₁₃ N ₃ 0 ₅ S)

Calculated: C _; 44.14; H, 4.38; N, 14.04; S ₎ 10.71.

Measured value: C, 43.94; H, 4.478; N, 14.09; S, 10.58.

(Fifth step)

Compound (5) 12.1 g, (40.48 mmol) and N- hydroxysuccinimide (4.66 g, 40,48 mM) under ice-cooling to THF (242 ml) suspension of,: DCC (8.35 g, 40.48 mmol) was added to 3 and the mixture was stirred for 10 minutes. The cooling bath was removed, and the mixture was further stirred at room temperature for 2 hours. The resulting compound N- hydroxysuccinimide ester solution of (5) was synthesized in a way described in the literature (Tetrahedron, 27, 2599 (1971 )) (R) – (+) – 2- Mechirupiro lysine hydrochloride (5.42 g) and Toryechiruamin (8.46 ml, was added at room temperature to THF (121 ml) suspension of 60.72 mmol). The reaction mixture was stirred for an additional 1 5 hrs. The filtrate after removal of the insoluble matter that has issued analysis was concentrated to dryness under reduced pressure. Residue (24.6 _Ga) the insoluble material was removed by filtration was dissolved in water (150 ml). The filtrate was purified by gel filtration column chromatography one (MCI Gel CHP-20P, 600 ml). 4 0% aqueous methanol solution compound of the collected crude eluted cut off fractionated (IX) was obtained 8.87 g. Then after purification by silica gel column chromatography (black port Holm one methanol mixture), to give the compound was freeze-dried (IX) 5.37 g (35.7% ).

mp: 192-194 ° C

[A] _D = -1.9 ° (C = 1.005, H ₂ 0, 25 ° C)

KB Cm- IR ¹ : 1755, 1675, 1625, 1541, 1516, 1448, 1232, 1097.

NMR (CD ₃ 0D): 8.97 (1H, t, J = 2.1 Hz), 7.34 (1H, t, J = 2.1 Hz), 5.19 and 5.04 (total the IH, the each t, J = 7.5 Hz), 4.92 (1H , Dq, J = 6.6 And 8.7 Hz), 4.36 And 4.35 (1H, D, J = 8.7 Hz), 4.07 And 3.92 (Total IH, Eac M), 3.78 (1H _; M), 3.42 (1¾ M), 3.22 (2H, m), 1.5-2.0 ( 4H, m), 1.28 and 1.22 (total 3H, each d, J = 6.6 Hz), 1.21 and 1.02 (total 3H, each d, J = 6.6 Hz).

Elemental analysis (C ₁₆ H ₂₂ N ₄ 0 ₄ S H ₂ 0)

Calculated: C, 49.99; H, 6.29; N, 14.57; S, 8.34.

Measured value: C, 49.99; H, 6.29; N, 14.79; S, 8.36.

PATENT

WO 2006028277

Example

Example 1

Step 1 l-N-[N<tert-butoxycarbonyl)-3-(^^^

N.N-dicyclohexylcarbodiimide (10.83 g, 52.5 mmol), N-hydroxybenzotriazole (2.03 g, 15 mmol) and triethylamine (7.7 ml, 55.2 mmol) were added to a solution (130 ml) of N-(tert-butoxycarbonyl)-3-(thiazol-4-yl)-L-alanine (1) (13.62 g, 50 mmol) obtained by the method described in literatures (J. Am. Chem. Soc. 73, 2935 (1951) and Chem. Pharm. Bull. 38, 103 (1950)) and 2(R)-2-methylpyrrolidine p-toluenesulfonic acid (2) (12.79 g, 50 mmol) obtained by the method described in a literature (HeIv. Chim. Acta, 34, 2202 (1951)) in tetrahydrofuran. The mixture was stirred for 20 hours at room temperature. After the precipitates are filtered off, the obtained filtrate was concentrated under reduced pressure. Thus-obtained residue was dissolved in ethyl acetate (200 ml) and the solution were washed with an aqueous solution of sodium hydrogencarbonate and water, successively. The organic layers were dried over magnesium sulfate and concentrated under reduced pressure to give a title compound (3) (16.45 g, 100%) as oil.

NMR (CDCl₃): O_H 8.76 and 8.75 (1 H, each d, J=2.1Hz, Thia-H-2), 7.08 (1 H, d, J=2.fflz, thia-H-5), 5.45 (1 H, m, NH), 3.45-3.64 (1 H, m, AIa-CoH), 4.14 and 3.81 (1 H, each m, Pyr-CαH), 3.51 (1 H, m, PVr-NCH₂), 3.1-3.4 (3 H, m, Pyr-CH₂and AIa-CH₂), 1.39 (9 H, s, BOC), 1.3-2.0 (4 H, m, PyT-CH₂), 1.06 (3 H, d, J=6Hz, Pyr-Me)

Step 2 l-N-[3-(thiazol-4-yl)-L-alanyl]-(2R)-2-methylpyrroHdine di-p-toluenesulfcnate (4)

Compound (3) (33.77 g, 99.48 mmol) and p-toluenesulfonic acid hydrate (37.85 g, 199 mmol) were dissolved in ethyl acetate (101 ml) and the solution was cooled with ice. To the mixture, 4 mol/L solution of hydrogen chloride-ethyl acetate (125 ml) was added, and the mixture was stirred for 2 hours 45 minutes. After the mixture was concentrated under reduced pressure, methanol was added to the residue. The mixture was concentrated. Methanol-toluene (1: 1) was added to the residue and concentrated under reduced pressure to give crystalline residue. The residue was washed with acetone and filtered to give compound (4) as crystals (36 g, 62%). After the mother liquor was concentrated under reduced pressure, methanol and toluene were added to the residue and concentrated. Obtained crystalline residue was washed with acetone to give compound (4) (10.67 g, 18.4%). mp 188-189 ⁰C [α]_D ²⁴ +2.2 (c, 1.0, MeOH) IR(KBr)Cm^“1: 3431, 3125, 3080, 2963, 1667, 1598, 1537, 1497, 1451, 1364, 1229, 1198, 1170, 1123, 1035, 1011.

NMR (CD₃OD): δ_H 9.04 and 9.03 (1 H, each d, J=2.1Hz, Thia-H-2), 7.70 (2 H, m, aromaticH), 7.46 (1H, d, J=2.1Hz, thia-H-5), 7.23 (2H, m, aromaticH), 4.49and4.46 (1 H, each d, J=6.9Hz, Ala-CαH), 4.14 and 3.75 (1 H, each m, Pyr-CαH), 3.51 (1 H, m, pyr-NCH₂), 3.2-3.4 (3 H, m, PyT-CH₂ and AIa-CH₂), 2.36 (3 H, s, aromatic Me), 1.3-2.0 (4 H, m, pyr-CH₂), 1.19 and 1.07 (3 H, each d, J=6.3Hz, Pyr-Me) Anal Calcd For C₁₁H₁₇N₃OS 2C₇H₈O₃S Calculated: C, 51.44%; H₁ 5.70%; N, 7.20%; S, 16.48%. Found: C, 51.36%; H, 5.69%; N, 7.23%; S, 16.31%.

Step 3 l-[N-[(4S,5S)-(5-methyl-2-oxooxazolidin-4-yl)carbonyl]-3-(thiazol-4-yl)-L-alanyl-(2R)-2- methylpyrrolidine trihydrate (I- 1) Step 3 (1) Method A

(4S, 5S)-5-methyl-2-oxooxazolidin-4-yl carboxylic acid (5) (1.368 g, 9.43 mmol) obtained by the method described in literatures (J. Chem. Soc. 1950, 62; Tetrahedron 48; 2507 (1992) and Angew. Chem. 101, 1392 (1989)), Compound (4) (5 g, 8.56 mmol) and N-hydiOxysuccinimide (217 mg, 1.89 mmol) were dissolved in N, N-dimethylformamide (10 ml), and tetrahydrofuran (65 ml) was added. After the mixture was cooled with ice in a cool bath, triethylamine (2.63 ml, 18.86 mmol) and N, N-dicyclohexylcarbodiimide (2.04 g, 9.89 mmol) were added with stirred and the mixture was stirred for additional 30 minutes. The cooling bath was removed and the mixture was stirred for 15 hours at room temperature. The precipitated were filtered off and the filtrate was concentrated under reduced pressure. Water (100 ml) was added to thus-obtained residue (9.95 g) and the mixture was stirred for 1.5 hours at room temperature. After insoluble substance was filtered off, the filtrate was concentrated until it was reduced to about half volume under reduced pressure. The small amount of insoluble substance was filtered off and the filtrate was concentrated until it was reduced to about 2O g under reduced pressure. After the mixture was allowed to stand in a refrigerator for 3 days, the precipitated crystals (2.98 g) were collected by filtration and washed with cold water. The filtrate was extracted twice with chloroform, dried over magnesium sulfate and concentrated under reduced pressure. Ethyl acetate (5 ml) was added to oil residue (1.05 g) and the mixture was stirred to give crystals (136 mg). The obtained crystals were combined and dissolved in purified water (45 ml) with heating. After the solution was allowed to cool to room temperature, the precipitated insoluble substance was filtered off The filtrate was concentrated under reduced pressure and allowed to stand at room temperature overnight. The mixture was cooled with ice, and the crystals were collected by filtration to give Compound (1-1, 2.89 g, 80.3%). mp 194-196 ⁰C

[α]_D ²² -2.0 ± 0.4 ° (c, 1.008, H₂O), [α]₃₆₅ +33.1 ± 0.7 ° (c, 1.008, H₂O)

IR(Nujor)cm”¹: 3517, 3342, 3276, 3130, 3092, 3060, 1754, 1682, 1610, 1551, 1465, 1442,

1379, 1235, 1089. NMR(CD₃OD): δ_H 8.97 and 8.96 (total 1 H, d, J=2.1Hz, Thia-H-2), 7.34 and 7.33 (total 1

H, d, J=2.1Hz, Thia-H-5), 5.18 and 5.04 (total 1 H, each t, J=7.5Hz, Ala-CαH), 4.92 (1

H, dq, J=6.6 and 8.7Hz, Oxa-H-5), 4.36 and 4.35 (total 1 H, d, J=8.7Hz, Oxa-H-4), 4.07 and 3.92 (total 1 H, each m, Pyr-Cα-H), 3.78 (1 H, m, Pyr-NCH₂), 3.42 (1 H, m, Pyr- 5 NCH₂), 3.22 (2 H, m, AIa-CH₂), 1.5-2.0 (4 H, m, Pyr-CH₂), 1.28 and 1.22 (total 3 H, each d, J=6.6Hz, Oxa-5-Me), 1.21 and 1.02 (total 3 H, each d, J=6.6Hz, Pyr-2-Me)

Anal. Calcd For C₁₆H₂₂N₄O₄S 3H₂O

Calculated: C, 45.00%; H, 6.71%; N, 13.33%; S, 7.63%.

Found: C, 45.49%; H, 6.60%; N, 13.58%, S, 7.88%. 10

Step 3 (2)

Method B

After Compound (1-2) (410 g, 1.119 mmol) was dissolved in purified water (6.3 L) with heating, the solution was concentrated until the total weight of the mixture was 15 reduced to 1370 g under reduced pressure. The concentrated solution was allowed to stand at room temperature overnight. The solution was cooled with ice for 1 hour and filtered to give the precipitated crystals. The obtained crystals were washed with cold water to give

Compound (T- 1) (448 g, 95.2%) as colorless crystals. Mother liquor was mixed with purified water (300 mL) with heating and the solution was concentrated to 55 g under reduced pressure. 20 After the concentrated solution was allowed to stand at room temperature overnight, the solution was filtered to give the precipitated crystals (T-1, 16.3 g, 3.5%, total amount 464.3 g, 98.7%). mp 194-196 ⁰C

[α]_D ²² -0.9 ± 0.4 ° (c, 1.007, H₂O), [α]₃₆₅ + 35.4 ± 0.8 ° (c, 1.007, H₂O)

IR(NuJOr)Cm^“1: 3511, 3348, 3276, 3130, 3093, 3060, 1755, 1739, 1682, 1611, 1551, 1465, 25. 1442, 1379, 1235, 1089.

AnalCalcdFor: C₁₆H₂₂N₄O₄S 3H₂O

Calculated: C, 45.00%;H, 6.71%;N, 13.33%; S, 7.63%.

Found: C, 45.56%; H, 6.66%; N, 13.43%, S, 7.69%.

30 Step 4 l-[N-[(4S₎5S)-(5-methyl-2-oxooxazolidin-4-yl)carbonyl]-3-(thiazol-4-yl)-L-alanyl-(2R)-2- methylpyrrolidine (1-2)

Method A

After l-[N-[(4S,5S)-(5-methyl-2-oxooxazolidin-4-yl)carbonyl]-3-(thiazol-4-yl)-L- 35 alanyl-(2R)-2-methylpyrrolidine monohydrate (4.77 g) obtained by the method described in Patent Literature 8 was crushed in a mortar, it was dried under reduced pressure (66.5 Pa) at 100 ⁰C for 15 hours to give 4.54 g of Compound (1-2). mp 194.5-196.5 ⁰C [α]_D ²⁵ -2.1 +. 0.4 ° (c, 1.004, H₂O), [α]₃₆₅ +36.8 ± 0.8 ° (c, 1.004, H₂O) Water measurement (Karl Fischer method): 0.27%

IR(NuJOr)Cm”¹: 3276, 3180, 3104, 1766, 1654, 1626, 1548, 1517, 1457, 1380, 1235, 1102, 979. NMR(CD₃OD):δ_H 8.97 and 8.96 (total 1 H, d, J 2.1 Hz, Thia-H-2), 7.34 and 7.33 (total 1 H, d, J 2.1 Hz, Thia-H-5), 5.19 and 5.04 (total 1 H, each t, J 7.5 Hz, Ala- CaH), 4.92 (1 H, dq, J 6.6 and 8.7 Hz, Oxa-H-5), 4.36 and 4.35 (total 1 H, d, J 8.7 Hz, Oxa-H-4), 4.07 and 3.92 (total 1 H, each m, Pyr-Cα-H), 3.78 (1 H, m, Pyr-NCH₂), 3.42 (1 H, m, Pyr-NCH₂), 3.22 (2 H, m, AIa-CH₂), 1.5-2.0 (4 H, m, Pyr-CH₂), 1.28 and 1.22 (total 3 H, each d, J 6.6 Hz, Oxa-5-Me), 1.21 and 1.02 (total 3 H, each d, J 6.6 Hz, Pyr-2-Me). Anal Calcd For: C₁₆H₂₂N₄O₄S

Calculated: C, 52.44%; H, 6.05%; N, 15.29%; S, 8.75%. Found: C, 52.24%; H, 5.98%; N, 15.27%, S, 8.57%.

Method B

After Compound (1-1) (17.89 g, 47.3 mmol) was crushed in a mortar, it was dried under reduced pressure (66.5 Pa) at 100 °C for 14 hours to give Compound (1-2, 17.31 g). mp 193-194 ⁰C [α]_D ²⁵ -1.9 ± 0.4 ° (c, 1.002, H₂O), [α]₃₆₅ +37.2 ± 0.8 ° (c, 1.002, H₂O)

Water measurement (Karl Fischer method): 0.22%

IR(NuJOr)Cm^“1: 3273, 3180, 3111, 1765, 1685, 1653, 1626, 1549, 1516, 1456, 1346, 1331,

1277, 1240, 1097, 980.

Anal Calcd For C₁₆H₂₂N₄O₄S Calculated: C, 52.44%; H, 6.05%; N, 15.29%; S, 8.75%.

Found: C, 52.19%; H, 5.98%; N, 15.42%, S, 8.74%.

REFERENCES

1: Ijiro T, Nakamura K, Ogata M, Inada H, Kiguchi S, Maruyama K, Nabekura J,
Kobayashi M, Ishibashi H. Effect of rovatirelin, a novel thyrotropin-releasing
hormone analog, on the central noradrenergic system. Eur J Pharmacol. 2015 Aug
15;761:413-22. doi: 10.1016/j.ejphar.2015.05.047. Epub 2015 Jul 2. PubMed PMID:
26142830.

////////Rovatirelin Hydrate, S-0373, Rovatirelin, 204386-76-5, clinical, phase 3

C[C@@H]1CCCN1C(=O)[C@H](Cc2cscn2)NC(=O)[C@@H]3[C@@H](OC(=O)N3)C

[F-18](2S,4S)-4-(3-Fluoropropyl)glutamine

Uncategorized Comments Off

May 302016

[F-18](2S,4S)-4-(3-Fluoropropyl)glutamine

CAS 1196963-79-7

MF C₈ H₁₅ F N₂ O₃

Heptanoic acid, 2-amino-4-(aminocarbonyl)-7-(fluoro-¹⁸F)-, (2S,4S)-


[¹⁸F](2S,4S)-4-FPGln	[¹⁸F](2S,4S)-4-(3-fluoropropyl)glutamine, 4

The early diagnosis of malignant tumors plays a very important role in the survival prognosis of cancer patients. In this non-invasive diagnosis, diagnostic imaging procedures are an important tool. In the last few years has mainly PET technology (P ositronen- E mission- Tomographie) proved to be particularly useful. The sensitivity and specificity of PET technology depends significantly on the used signal-emitting substance (tracer) and their distribution in the body from. In the search for suitable tracers one tries to take advantage of certain properties of tumors differ, the tumor tissue from healthy, surrounding tissue. The preferred commercially used isotope which finds application for PET, ¹⁸ F ¹⁸ F represents by its short half-life of less than 2 hours special requirements for the preparation of suitable tracer. Complex, long synthetic routes and purifications are with this isotope is not possible, because otherwise a significant portion of the radioactivity of the isotope has already decayed before the tracer can be used for diagnosis. It is therefore often not possible to established synthetic routes for non-radioactive fluorination to be applied to the synthesis of¹⁸ F-tracer. Furthermore, the high specific activity of ¹⁸ F (80 GBq / nmol) at very low substance amounts of ^[18 F] fluoride for the tracer synthesis, which in turn an extreme excess of precursor-related and the success of a non-radioactive fluorination based Radio synthetic strategy designed unpredictable

FDG ^([18 F] F 2 luoro d esoxy lukose g) -PET is a widely accepted and popular tool in the diagnosis and other clinical tracking of tumor diseases. Malignant tumors compete with the host organism to glucose supply to the nutrient supply (Warburg O. About the metabolism of carcinoma cell Biochem;.. Kellof G. Progress and Promise of FDG PET Imaging for Cancer Patient Management and Oncologic Drug Development Clin Cancer Res 2005;.. 11 (8): 2785-2807) where tumor cells compared to surrounding cells of normal tissue usually an increased glucose metabolism. This is used when using fluorodeoxyglucose (FDG), a glucose derivative, which is amplified transported into the cells, but there included metabolically after phosphorylation as FDG-6-phosphate (“Warburg effect”). ¹⁸ F-labeled FDG is Therefore, an effective tracer for the detection of tumors in patients using PET technology. Imaging were looking for new PET tracers in recent years increasingly amino acids for ¹⁸ F PET used (eg (review): Eur J Nucl Med Mol Imaging 2002 May; 29 (5):.. 681-90). In this case, some of the ¹⁸ F-labeled amino acids for the measurement of the speed rate of protein synthesis, the most useful derivatives but for the direct measurement of the cellular uptake in the tumor. Known ¹⁸ F-labeled amino acids are, for example, from tyrosine, phenylalanine, proline, aspartic and unnatural amino acids derived (eg J. Nucl Med 1991; 32:.. 1338-1346, J Nucl Med 1996; 37: 320-325, J Nucl Med 2001; 42: 752-754 J Nucl Med and 1999, 40: 331-338).. Glutamic acid and glutamine than ¹⁸ F-labeled derivatives not known, whereas non-radioactive fluorinated glutamine and glutamic acid derivatives are well known; Thus, for Example those which at γ-position (for Ex (review):Amino Acids (2003) April; 24 (3):… 245-61).. or at β-position (e.g. ExTetrahedron. Lett. .; 30; 14; 1989, 1799-1802, J. Org Chem .; 54; 2; 1989, 498-500, Tetrahedron: Asymmetry, 12, 9; 2001; 1303-1312) havefluorine..

Of glutamic acid having the chemical functionalities protecting groups in β and γ position or a leaving group, has already been reported in the past. So was informed of glutamate as mesylate or bromide in γ-position whose acid and amine functions were provided with ester or Z-protecting groups (J. Chem Soc Perkin Trans. 1;.. 1986, 1323-1328) or, for example, of γ-chloro-glutamic acid without protecting groups(Synthesis, (1973); 44-46). About similar derivatives, but where the leaving group is positioned in β-position has also been reported on several occasions. Z Ex. Chem. Pharm. Bull .; 17; 5; (1969); 879-885,J.Gen.Chem.USSR (Engl.Transl.); 38; (1968); 1645-1648, Tetrahedron Lett .; 27; 19; (1986); 2143-2144, Chem. Pharm. Bull .; EN; 17; 5; 1969;873-878, patent FR 1461184 , Patent JP 13142 .)

The current PET tracers, which are used for tumor diagnosis have some undisputed disadvantages: in FDG accumulates preferably in those cells with increased glucose metabolism on, but there are also other pathological and physiological conditions of increased glucose metabolism in the cells involved and tissues, eg, Ex. of infection or wound healing (summarized in J. Nucl. Med. Technol. (2005), 33, 145-155). It is still often difficult to decide whether a detected by FDG-PET lesion actually neoplastic origin or due to other physiological or pathological state of the tissue. Overall, the diagnostic activity by FDG-PET in oncology has a sensitivity of 84% and a specificity of 88% to(Gambhir et al., ” A tabulated summary of the FDG PET literature “J. Nucl. Med. 2001, 42, 1- 93S). Tumors in the brain can be represented very difficult in healthy brain tissue, for example, by the high accumulation of FDG.

The previously known ¹⁸ F-labeled amino acid derivatives are in some cases well suited to detect tumors in the brain ((review): Eur J Nucl Med Mol Imaging 2002 May; 29 (5):. 681-90), but they can in other tumors do not compete with the imaging properties of the “gold standard” ^[18 F] 2-FDG. The metabolic accumulation and retention of previously F-18 labeled amino acids in tumorous tissue is usually lower than for FDG. Moreover, the accessibility of isomerically pure F-18-labeled non-aromatic amino acids is chemically very demanding.

Similar to glucose increased metabolism in proliferating tumor cells has been described (Medina, J Nutr 1131: 2539S-2542S, 2001; Souba, Ann Surg 218:. 715-728, 1993) for glutamic acid and glutamine. The increased rate of protein and nucleic acid synthesis and energy production per se be accepted as reasons for increased Glutaminkonsum of tumor cells. The synthesis of the corresponding C-11 and C-14 labeled with the natural substrate thus identical compounds, has already been described in the literature (eg. Ex.Antoni, enzymes Catalyzed Synthesis of L- [4-C-11] Aspartate and L – [5-C-11] Glutamate J. Labelled Compd Radiopharm 44; (4) 2001: 287-294) and Buchanan, The biosynthesis of showdomycin: studies with stable isotopes and the determination of principal precursor J….. Chem. Soc. Chem. Commun .; EN; 22; 1984, 1515-1517). First indications with the C-11 labeled compound indicate no significant tumor accumulation.

Although the growth and proliferation of most tumors is fueled by glucose, some tumors are more likely to metabolize glutamine. In particular, tumor cells with the upregulated c-Myc gene are generally reprogrammed to utilize glutamine. We have developed new 3-fluoropropyl analogs of glutamine, namely [(18)F](2S,4R)- and [(18)F](2S,4S)-4-(3-fluoropropyl)glutamine, 3 and 4, to be used as probes for studying glutamine metabolism in these tumor cells. Optically pure isomers labeled with (18)F and (19)F (2S,4S) and (2S,4R)-4-(3-fluoropropyl)glutamine were synthesized via different routes and isolated in high radiochemical purity (≥95%). Cell uptake studies of both isomers showed that they were taken up efficiently by 9L tumor cells with a steady increase over a time frame of 120 min. At 120 min, their uptake was approximately two times higher than that of l-[(3)H]glutamine ([(3)H]Gln). These in vitro cell uptake studies suggested that the new probes are potential tumor imaging agents. Yet, the lower chemical yield of the precursor for 3, as well as the low radiochemical yield for 3, limits the availability of [(18)F](2S,4R)-4-(3-fluoropropyl)glutamine, 3. We, therefore, focused on [(18)F](2S,4S)-4-(3-fluoropropyl)glutamine, 4. The in vitro cell uptake studies suggested that the new probe, [(18)F](2S,4S)-4-(3-fluoropropyl)glutamine, 4, is most sensitive to the LAT transport system, followed by System N and ASC transporters. A dual-isotope experiment using l-[(3)H]glutamine and the new probe showed that the uptake of [(3)H]Gln into 9L cells was highly associated with macromolecules (>90%), whereas the [(18)F](2S,4S)-4-(3-fluoropropyl)glutamine, 4, was not (<10%). This suggests a different mechanism of retention. In vivo PET imaging studies demonstrated tumor-specific uptake in rats bearing 9L xenographs with an excellent tumor to muscle ratio (maximum of ∼8 at 40 min). [(18)F](2S,4S)-4-(3-fluoropropyl)glutamine, 4, may be useful for testing tumors that may metabolize glutamine related amino acids.

[¹⁸F](2S,4S)-4-(3-Fluoropropyl)glutamine as a Tumor Imaging Agent

http://pubs.acs.org/doi/full/10.1021/mp500236y

Zehui Wu†, Zhihao Zha†, Genxun Li†, Brian P. Lieberman†, Seok Rye Choi†, Karl Ploessl†, and Hank F. Kung^*†‡

^†Departments of Radiology and ^‡Pharmacology, University of Pennsylvania, 3700 Market Street, Philadelphia, Pennsylvania 19104, United States

Mol. Pharmaceutics, 2014, 11 (11), pp 3852–3866

DOI: 10.1021/mp500236y

Publication Date (Web): August 05, 2014

*Email: kunghf@sunmac.spect.upenn.edu. Phone: 215-662-3096. Fax: 215-349-5035.

ACS AuthorChoice – This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes.

This article is part of the Positron Emission Tomography: State of the Art special issue.

Abstract

Although the growth and proliferation of most tumors is fueled by glucose, some tumors are more likely to metabolize glutamine. In particular, tumor cells with the upregulated c-Myc gene are generally reprogrammed to utilize glutamine. We have developed new 3-fluoropropyl analogs of glutamine, namely [¹⁸F](2S,4R)- and [¹⁸F](2S,4S)-4-(3-fluoropropyl)glutamine, 3 and 4, to be used as probes for studying glutamine metabolism in these tumor cells. Optically pure isomers labeled with ¹⁸F and ¹⁹F (2S,4S) and (2S,4R)-4-(3-fluoropropyl)glutamine were synthesized via different routes and isolated in high radiochemical purity (≥95%). Cell uptake studies of both isomers showed that they were taken up efficiently by 9L tumor cells with a steady increase over a time frame of 120 min. At 120 min, their uptake was approximately two times higher than that of l-[³H]glutamine ([³H]Gln). These in vitro cell uptake studies suggested that the new probes are potential tumor imaging agents. Yet, the lower chemical yield of the precursor for 3, as well as the low radiochemical yield for 3, limits the availability of [¹⁸F](2S,4R)-4-(3-fluoropropyl)glutamine, 3. We, therefore, focused on [¹⁸F](2S,4S)-4-(3-fluoropropyl)glutamine, 4. The in vitro cell uptake studies suggested that the new probe, [¹⁸F](2S,4S)-4-(3-fluoropropyl)glutamine, 4, is most sensitive to the LAT transport system, followed by System N and ASC transporters. A dual-isotope experiment using l-[³H]glutamine and the new probe showed that the uptake of [³H]Gln into 9L cells was highly associated with macromolecules (>90%), whereas the [¹⁸F](2S,4S)-4-(3-fluoropropyl)glutamine, 4, was not (<10%). This suggests a different mechanism of retention. In vivo PET imaging studies demonstrated tumor-specific uptake in rats bearing 9L xenographs with an excellent tumor to muscle ratio (maximum of ∼8 at 40 min). [¹⁸F](2S,4S)-4-(3-fluoropropyl)glutamine, 4, may be useful for testing tumors that may metabolize glutamine related amino acids.

PATENT

US 20100290991

http://www.google.com/patents/US20100290991

PATENT

WO 2009141091

https://patentscope.wipo.int/search/ko/detail.jsf?docId=WO2009141091&recNum=70&maxRec=287&office=&prevFilter=%26fq%3DOF%3ACU&sortOption=Relevance&queryString=&tab=PCTDescription

PATENT

http://www.google.co.ug/patents/EP2123621A1?cl=en

REFERENCES

https://www.researchgate.net/publication/264538736_F-182S4S-4-3-Fluoropropylglutamine_as_a_Tumor_Imaging_Agent

Molecular Pharmaceutics (2014), 11(11), 3852-3866

EP1923382A1 *	18 Nov 2006	21 May 2008	Bayer Schering Pharma Aktiengesellschaft	[18F] labelled L-glutamic acid, [18F] labelled glutamine, their derivatives, their use and processes for their preparation
FR1461184A				Title not available
JPS58113142A				Title not available
WO2008052788A1 *	30 Oct 2007	8 May 2008	Bayer Schering Pharma Aktiengesellschaft	[f-18]-labeled l-glutamic acid, [f-18]-labeled l-glutamine, derivatives thereof and use thereof and processes for their preparation

////////

FDA approves new diagnostic imaging agent FLUCICLOVINE F-18 to detect recurrent prostate cancer

FDA 2016, Uncategorized Comments Off

May 282016

FLUCICLOVINE F-18

Cyclobutanecarboxylic acid, 1-amino-3-(fluoro-¹⁸F)-, trans- [

Molecular FormulaC₅H₈¹⁸FNO₂
Average mass132.124 Da

Axumin (fluciclovine F 18)

fluciclovinum (¹⁸F)

GE-148

NMK36

trans-1-Amino-3-(¹⁸F)fluorcyclobutancarbonsäure [German] [ACD/IUPAC Name]

trans-1-Amino-3-(¹⁸F)fluorocyclobutanecarboxylic acid [ACD/IUPAC Name]

UNII-38R1Q0L1ZE

anti-1-amino-3-[18F]fluorocyclobutane-1-carboxylic acid

cas 222727-39-1

FDA approves new diagnostic imaging agent to detect recurrent prostate cancer

05/27/2016 11:27 AM EDT

The U.S. Food and Drug Administration today approved Axumin, a radioactive diagnostic agent for injection. Axumin is indicated for positron emission tomography (PET) imaging in men with suspected prostate cancer recurrence based on elevated prostate specific antigen (PSA) levels following prior treatment.

May 27, 2016

Release

Prostate cancer is the second leading cause of death from cancer in U.S. men. In patients with suspected cancer recurrence after primary treatment, accurate staging is an important objective in improving management and outcomes.

“Imaging tests are not able to determine the location of the recurrent prostate cancer when the PSA is at very low levels,” said Libero Marzella, M.D., Ph.D., director of the Division of Medical Imaging Products in the FDA’s Center for Drug Evaluation and Research. “Axumin is shown to provide another accurate imaging approach for these patients.”

Two studies evaluated the safety and efficacy of Axumin for imaging prostate cancer in patients with recurrent disease. The first compared 105 Axumin scans in men with suspected recurrence of prostate cancer to the histopathology (the study of tissue changes caused by disease) obtained by prostate biopsy and by biopsies of suspicious imaged lesions. Radiologists onsite read the scans initially; subsequently, three independent radiologists read the same scans in a blinded study.

The second study evaluated the agreement between 96 Axumin and C11 choline (an approved PET scan imaging test) scans in patients with median PSA values of 1.44 ng/mL. Radiologists on-site read the scans, and the same three independent radiologists who read the scans in the first study read the Axumin scans in this second blinded study. The results of the independent scan readings were generally consistent with one another, and confirmed the results of the onsite scan readings. Both studies supported the safety and efficacy of Axumin for imaging prostate cancer in men with elevated PSA levels following prior treatment.

Axumin is a radioactive drug and should be handled with appropriate safety measures to minimize radiation exposure to patients and healthcare providers during administration. Image interpretation errors can occur with Axumin PET imaging. A negative image does not rule out the presence of recurrent prostate cancer and a positive image does not confirm the presence of recurrent prostate cancer. Clinical correlation, which may include histopathological evaluation of the suspected recurrence site, is recommended.

The most commonly reported adverse reactions in patients are injection site pain, redness, and a metallic taste in the mouth.

Axumin is marketed by Blue Earth Diagnostics, Ltd., Oxford, United Kingdom

Patent

http://www.google.com/patents/WO2014023775A1?cl=en

The non-natural amino acid [ F]-l-amino-3-fluorocyclobutane-l-carboxylic acid

([¹⁸F]-FACBC, also known as [¹⁸F]-Fluciclovine) is taken up specifically by amino acid transporters and has shown promise for tumour imaging with positron emission tomography (PET).

A known synthesis of [¹⁸F]-FACBC begins with the provision of the protected precursor compound 1 -(N-(t-butoxycarbonyl)amino)-3 –

[((trifluoromethyl)sulfonyl)oxy]-cyclobutane-l-carboxylic acid ethyl ester. This precursor compound is first labelled with [¹⁸F]-fluoride:

II before removal of the two protecting groups:

IT III

EP2017258 (Al) teaches removal of the ethyl protecting group by trapping the [¹⁸F]- labelled precursor compound (II) onto a solid phase extraction (SPE) cartridge and incubating with 0.8 mL of a 4 mol/L solution of sodium hydroxide (NaOH). After 3 minutes incubation the NaOH solution was collected in a vial and a further 0.8 mL 4 mol/L NaOH added to the SPE cartridge to repeat the procedure. Thereafter the SPE cartridge was washed with 3 mL water and the wash solution combined with the collected NaOH solution. Then 2.2 mL of 6 mol/L HCl was then added with heating to 60°C for 5 minutes to remove the Boc protecting group. The resulting solution was purified by passing through (i) an ion retardation column to remove Na⁺ from excess NaOH and Cl^~ from extra HCl needed to neutralise excess of NaOH to get a highly acidic solution before the acidic hydrolysis step, (ii) an alumina column, and (iii) a reverse-phase column. There is scope for the deprotection step(s) and/or the

purification step in the production of [¹⁸F]-FACBC to be simplified.

Example 1: Synthesis of f FIFACBC

No-carrier- added [¹⁸F]fluoride was produced via the ¹⁸0(p,n)¹⁸F nuclear reaction on a GE PETtrace 6 cyclotron (Norwegian Cyclotron Centre, Oslo). Irradiations were performed using a dual-beam, 30μΑ current on two equal Ag targets with HAVAR foils using 16.5 MeV protons. Each target contained 1.6 ml of > 96% [¹⁸0]water (Marshall Isotopes). Subsequent to irradiation and delivery to a hotcell, each target was washed with 1.6 ml of [¹⁶0]water (Merck, water for GR analysis), giving approximately 2-5 Gbq in 3.2 ml of [¹⁶0]water. All radiochemistry was performed on a commercially available GE FASTlab™ with single-use cassettes. Each cassette is built around a one-piece-moulded manifold with 25 three-way stopcocks, all made of polypropylene. Briefly, the cassette includes a 5 ml reactor (cyclic olefin copolymer), one 1 ml syringe and two 5 ml syringes, spikes for connection with five prefilled vials, one water bag (100 ml) as well as various SPE cartridges and filters. Fluid paths are controlled with nitrogen purging, vacuum and the three syringes. The fully automated system is designed for single-step fluorinations with cyclotron-produced [¹⁸F]fluoride. The FASTlab was programmed by the software package in a step-by-step time-dependent sequence of events such as moving the syringes, nitrogen purging, vacuum, and temperature regulation. Synthesis of

[¹⁸F]FACBC followed the three general steps: (a) [¹⁸F]fluorination, (b) hydrolysis of protection groups and (c) SPE purification.

Vial A contained K₂₂₂ (58.8 mg, 156 μπιοΐ), K₂C0₃ (8.1 mg, 60.8 μπιοΐ) in 79.5% (v/v)

MeCN(a_q) (1105 μΐ). Vial B contained 4M HC1 (2.0 ml). Vial C contained MeCN

(4.1ml). Vial D contained the precursor (48.4 mg, 123.5 μιηοΐ) in its dry form (stored at -20 °C until cassette assembly). Vial E contained 2 M NaOH (4.1 ml). The 30 ml product collection glass vial was filled with 200 mM trisodium citrate (10 ml). Aqueous

[¹⁸F]fluoride (1-1.5 ml, 100-200 Mbq) was passed through the QMA and into the ¹⁸0-

H₂0 recovery vial. The QMA was then flushed with MeCN and sent to waste. The trapped [¹⁸F]fluoride was eluted into the reactor using eluent from vial A (730 μΐ) and then concentrated to dryness by azeotropic distillation with acetonitrile (80 μΐ, vial C). Approximately 1.7 ml of MeCN was mixed with precursor in vial D from which 1.0 ml of the dissolved precursor (corresponds to 28.5 mg, 72.7 mmol precursor) was added to the reactor and heated for 3 min at 85°C. The reaction mixture was diluted with water and sent through the tC18 cartridge. Reactor was washed with water and sent through the tC18 cartridge. The labelled intermediate, fixed on the tC18 cartridge was washed with water, and then incubated with 2M NaOH (2.0 ml) for 5 min after which the 2M NaOH was sent to waste. The labelled intermediate (without the ester group) was then eluted off the tC18 cartridge into the reactor using water. The BOC group was hydrolysed by adding 4M HC1 (1.4 ml) and heating the reactor for 5 min at 60 °C. The reactor content with the crude [¹⁸F]FACBC was sent through the HLB and Alumina cartridges and into the 30 ml product vial. The HLB and Alumina cartridges were washed with water (9.1 ml total) and collected in the product vial. Finally, 2M NaOH (0.9 ml) and water (2.1 ml) was added to the product vial, giving a purified formulation of [¹⁸F]FACBC with a total volume of 26 ml. Radiochemical purity was measured by radio-TLC using a mixture of MeCN:MeOH:H₂0:CH₃COOH (20:5:5: 1) as the mobile phase. The radiochemical yield (RCY) was expressed as the amount of radioactivity in the [¹⁸F]FACBC fraction divided by the total used [¹⁸F]fluoride activity (decay corrected). Total synthesis time was 43 min.

The RCY of [¹⁸F]FACBC was 62.5% ± 1.93 (SD), n=4.

/////FDA, diagnostic imaging agent, recurrent prostate cancer, fda 2016, Axumin, marketed, Blue Earth Diagnostics, Ltd., Oxford, United Kingdom, fluciclovine F 18

C1[C@@](C[C@H]1[18F])(N)C(=O)O

Flow approach towards AZD 6906

flow synthesis, PROCESS Comments Off

May 272016

Scheme 1: Flow approach towards AZD6906 (65).

PIC CREDIT, The synthesis of active pharmaceutical ingredients (APIs) using continuous flow chemistry, Marcus Baumann and Ian R. Baxendale, Beilstein J. Org. Chem. 2015, 11, 1194–1219.,doi:10.3762/bjoc.11.134

In 2012 researchers from AstraZeneca (Sweden) reported upon a scale-up campaign for their gastroesophageal reflux inhibitor programme. Specifically, flow chemical synthesis was used to efficiently and reliably provide sufficient quantities of the target compound AZD6906 (65), which had been prepared previously in batch. From these earlier batch studies concerns had been raised regarding exothermic reaction profiles as well as product instability which needed to be addressed when moving to larger scale synthesis. Flow was identified as a potential way of circumventing these specific problems and so was extensively investigated. The developed flow route [1 ] started with the reaction of methyl dichlorophosphine (66) and triethyl orthoacetate (67), which in batch could only be performed under careful addition of the reagent and external cooling using dry ice/acetone. Pleasingly, a simple flow setup in which the two streams of neat reagents were mixed in a PTFE T-piece maintained at 25 °C was found effective in order to prepare the desired adduct 68 in high yield and quality showcasing the benefits of superior heat dissipation whilst also safely handling the toxic and pyrophoric methyl dichlorophosphine reagent (Scheme 1).

As the subsequent Claisen condensation step was also known to generate a considerable exotherm, a similar flow setup was used in order to allow the reaction heat to dissipate. The superiority of the heat transfer process even allowed this step to be performed on kilogram quantities of both starting materials (68, 69) at a reactor temperature of 35 °C giving the desired product 72 within a residence time of only 90 seconds. Vital to the successful outcome was the efficient in situ generation of LDA from n-BuLi and diisopropylamine as well as the rapid quenching of the reaction mixture prior to collection of the crude product. Furthermore, flow processing allowed for the reaction of both substrates in a 1:1 ratio (rather than 2:1 as was required in batch) as the immediate quenching step prevented side reactions taking place under the strongly basic conditions. Having succeeded in safely preparing compound 72 on kilogram scale, the target compound 65 was then generated by global deprotection and subsequent recrystallisation where batch was reverted to as the conditions had been previously devised and worked well.

Marcus

Dr Marcus Baumann
Postdoc

Marcus Baumann studied chemistry at the Philipps-University Marburg/Germany, from where he graduated in 2007. His studies involved a 6 month period as an Erasmus student at the Innovative Technology Centre at the University of Cambridge, UK (with Prof. Steven V. Ley and Dr Ian R. Baxendale), where he developed a new flow-based oxazole synthesis. He soon returned to Cambridge to pursue his doctoral studies with Prof. Steven V. Ley where he developed flow processes for Curtius rearrangements, different fluorination reactions as well as important heterocycle syntheses. Upon completion of his PhD in 2010 Marcus was awarded a Feodor Lynen Postdoctoral Fellowship (Alexander von Humboldt Foundation, Germany) allowing him to join the group of Prof. Larry E. Overman at UC Irvine, USA (2011-2013). During his time in California his research focused on the synthesis of naturally occurring terpenes as well as analogues of ETP-alkaloids. The latter project generated potent and selective histone methyltransferase inhibitors and opened routes towards new probes for epigenetic diseases which are currently under further investigation. In early 2013 Marcus returned to the UK and took up a postdoctoral position with Prof. Ian R. Baxendale at the University of Durham, where his interests concentrate on the development of flow and batch based strategies towards valuable compounds en route for regenerative medicines.

Prof. Ian R. Baxendale

Personal web page

Professor in the Department of Chemistry

Telephone: +44 (0) 191 33 42185

Member in the Centre for Sustainable Chemical Processes

(email at i.r.baxendale@durham.ac.uk)

Research Interests

My general areas of interest are: Organic synthesis (natural products, heterocyclic and medicinal chemistry), Organometallic chemistry, Catalyst design and application, Meso flow chemistry, Microfluidics, Microwave assisted synthesis, Solid supported reagents and scavengers, and facilitated reaction optimisation using Robotics and Automation.

My primary research direction is the synthesis of biologically potent molecules which encompasses the design, development and integration of new processing techniques for their preparation and solving challenges associated with the syntheses of new pharmaceutical and agrochemical compounds. In our work we utilise the latest synthesis tools and enabling technologies such as microwave reactors, solid supported reagents and scavengers, enzymes, membrane reactors and flow chemistry platforms to facilitate the bond making sequence and expedite the purification procedure. A central aspect of our investigations is our pioneering work on flow chemical synthesis and microreactor technology as a means of improving the speed, efficiency, and safety of various chemical transformations. As a part of these studies we are attempting to devise new chemical reactions that are not inherently feasible or would be problematic under standard laboratory conditions. It is our further challenge to enhance the automation associated with these reactor devices to impart a certain level of intelligence to their function so that repetitive wasteful actions currently performed by chemists can be delegated to a machine; for example, reagent screening or reaction optimisation. We use these technologies as tools to enhance our synthetic capabilities but strongly believe in not becoming slaves to any methodology or equipment.

For those interested in our research and wishing to find out more we invite you to visit our website at: http://www.dur.ac.uk/i.r.baxendale/

Early scale-up work of a promising reflux inhibitor AZD6906 is described. Two steps of an earlier route were adapted to be performed in continuous flow to avoid issues related to batch procedures, resulting in a robust method with reduced cost of goods and improved product quality. Toxic and reactive reagents and starting materials could be handled in a flow regime, thereby allowing safer and more convenient reaction optimization and production.

Gustafsson, T.; Sörensen, H.; Pontén, F. Org. Process Res. Dev. 2012, 16, 925–929. doi:10.1021/op200340c

Development of a Continuous Flow Scale-Up Approach of Reflux Inhibitor AZD6906

Tomas Gustafsson, Henrik Sörensen, and Fritiof Pontén*

Medicinal Chemistry, AstraZeneca R&D Mölndal, SE-431 83 Mölndal, Sweden

Org. Process Res. Dev., 2012, 16 (5), pp 925–929

DOI: 10.1021/op200340c

Publication Date (Web): February 21, 2012

*Telephone: +46 31 776 16 65. Email: fritiof.ponten@astrazeneca.com.

This article is part of the Continuous Processes 2012 special issue.

One benefit of flow reactors is improved control over reaction temperature, due to reduced reaction volume at a given time, higher surface area, and the movement of the reaction mixture. This is particularly helpful for very exothermic reactions, which often require cryogenic cooling to prevent runaway reactions – this type of cooling is very expensive and resource-intensive on a large scale. One such reaction is described in a recent paper from AstraZeneca, in which a phosphinate anion adds into a glycine derivative. The product of this reaction is an intermediate in the synthesis of a gastroesophageal reflux inhibitor drug candidate called AZD6906.

////Flow synthesis, AZD 6906

Flow synthesis of Fluoxetine

Uncategorized Comments Off

May 272016

Scheme 1: Flow synthesis of fluoxetine (46).

One of the early published examples of industry-based research on multi-step flow synthesis of a pharmaceutical was reported in 2011 by scientists from Eli Lilly/UK and detailed the synthesis of fluoxetine 46, the API of Prozac[1]. In this account each step was performed and optimised individually in flow, with analysis and purification being accomplished off-line. The synthesis commences with the reduction of the advanced intermediate ketone 47 using a solution of pre-chilled borane–THF complex (48) to yield alcohol 49 (Scheme 1).

Conversion of the pendant chloride into iodide 51 was attempted via Finckelstein conditions, however, even when utilising phase-transfer conditions in order to maintain a homogeneous flow regime the outcome was not satisfactory giving only low conversions. Alternatively direct amination of chloride 49 utilising high temperature flow conditions (140 °C) allowed the direct preparation of amine 50 in excellent yield.

Flow processing using a short residence time (10 min) at the elevated temperature allowed for a good throughput; in addition, the handling of the volatile methylamine within the confines of the flow reactor simplifies the practical aspects of the transformation, however, extra precautions were required in order to address and remove any leftover methylamine that would pose a significant hazard during scaling up.

The final arylation of 50 was intended to be performed as a S_NAr reaction, however, insufficient deprotonation of the alcohol 50 under flow conditions (NaHMDS or BEMP instead of using a suspension of NaH as used in batch) required a modification to the planned approach. To this end a Mitsunobu protocol based on the orchestrated mixing of four reagent streams (50, 54 and reagents 52 and 53) was developed and successfully applied to deliver fluoxetine (46) in high yield.

Overall, this study is a good example detailing the intricacies faced when translating an initial batch synthesis into a sequence of flow steps for which several adaptations regarding choice of reagents and reaction conditions are mandatory in order to succeed.

Ahmed-Omer, B.; Sanderson, A. J. Org. Biomol. Chem. 2011, 9, 3854–3862. doi:10.1039/C0OB00906G
Paper

Preparation of fluoxetine by multiple flow processing steps

Batoul Ahmed-Omer^a and Adam J. Sanderson*^a

*Corresponding authors

^aEli Lilly and Co. Ltd., Lilly Research Centre, Erl Wood Manor, Windlesham, Surrey, UK

Org. Biomol. Chem., 2011,9, 3854-3862

DOI: 10.1039/C0OB00906G

http://pubs.rsc.org/en/Content/ArticleLanding/2011/OB/c0ob00906g#!divAbstract

Microflow technology is established as a modern and fashionable tool in synthetic organic chemistry, bringing great improvement and potential, on account of a series of advantages over flask methods. The study presented here focuses on the application of flow chemistry process in performing an efficient multiple step syntheses of (±)-fluoxetine as an alternative to conventional synthetic methods, and one of the few examples of total synthesis accomplished by flow technique.

Graphical abstract: Preparation of fluoxetine by multiple flow processing steps

1 The general method set-up of flow process used for the synthesis of (±)- fluoxetine.

Scheme 1 Synthesis of (±)-fluoxetine in flow: (i) BH3·THF, r.t., 5 min (77%); (ii) NaI, toluene: water, 100 °C, 20 min (43%); (iii); MeNH2 (aq), …

//////////Flow synthesis, fluoxetine

SETIPIPRANT

Uncategorized Comments Off

May 272016

Setipiprant, KYTH-105

CAS 866460-33-5

2-(2-(1-naphthoyl)-8-fluoro-1,2,3,4-tetrahydropyrido[4,3-b]indol-5-yl)acetic acid

2-[8-fluoro-2-(naphthalene-1-carbonyl)-3,4-dihydro-1H-pyrido[4,3-b]indol-5-yl]acetic acid

5H-Pyrido(4,3-b)indole-5-acetic acid, 8-fluoro-1,2,3,4-tetrahydro-2-(1-naphthalenylcarbonyl)-

MF C24H19FN2O3

MW 402.4176632

IND FILED BY ALLERGAN FOR Alopecia

ACT-129968, a CRTH2 receptor antagonist, had been in phase II clinical trials at Actelion

Setipiprant; UNII-BHF20LA2GM; ACT-129968; 866460-33-5;

Setipiprant is a prostaglandin D2 (PGD2) antagonist. Essentially, it inhibits PGD2 receptor activity

KYTH-105 had previously been studied as a potential allergic inflammation treatment and had undergone eight clinical trials, resulting in a safety database of more than 1,000 patients. Treatment in all studies was well tolerated across all treatment groups.

Intellectual Property
KYTHERA acquired exclusive worldwide rights to KYTH-105, as well as certain patent rights covering the use of PGD2 receptor antagonists for the treatment of hair loss (often presenting as male pattern baldness, or androgenic alopecia).

Next Steps
KYTHERA plans to file an Investigational New Drug (IND) application and initiate a proof-of-concept study to establish the efficacy of KYTH-105 in male subjects with androgenic alopecia (AGA).

In 2015, Allergan acquired Kythera.

2-(2-(1-Naphthoyl)-8-fluoro-3,4-dihydro-1H-pyrido[4,3-b]indol-5(2H)-yl)acetic Acid

mp 224.0 °C.

LC(1)/ESI-MS t_R = 0.83 min; m/z [M + H⁺] = 403.09.

¹H NMR (DMSO-d₆), 65:35 mixture of two rotamers, δ: 8.02 (m, 2 H), 7.76 (d, J = 7.8 Hz, 0.65 H), 7.72 (m, 0.35 H), 7.49–7.64 (m, 3.35 H), 7.35–7.49 (m, 2.35 H), 6.98 (ddd, J_H–F = 9.3 Hz, J₁ = 9.3 Hz, J₂ = 2.4 Hz, 0.65 H), 6.88 (m, 0.65 H), 4.85–5.14 (m, 3.3 H), 4.42 (m, 0.35 H), 4.32 (m, 0.7 H), 4.06 (m, 0.35 H), 3.50 (t, J = 5.5 Hz, 1.3 H), 2.95 (m, 0.70 H), 2.68 (m, 0.65 H), 2.58 (m, 0.65 H).

¹³C NMR (DMSO-d₆) δ: 170.7, 169.2, 157.7 (d, J_C–F = 232 Hz), 157.4 (d, J_C–F = 233 Hz), 137.1, 136.2, 135.1, 134.9, 134.0, 133.8, 133.5, 129.6, 129.5, 129.4, 129.3, 128.9, 128.8, 127.5, 127.4, 127.0, 126.9, 126.0, 125.9, 125.7 (d, J_C–F = 10 Hz), 125.2, 125.1, 125.0, 124.1, 123.9, 110.9 (d, J_C–F = 10 Hz), 110.8 (m), 109.3 (d, J_C–F = 26 Hz), 109.1 (d, J_C–F = 26 Hz), 106.7 (m), 103.3 (d, J_C–F = 23 Hz), 103.0 (d, J_C–F = 23 Hz), 44.73, 44.70, 44.5, 44.4, 39.5, 39.3, 23.1, 22.3.

HRMS (ESI): m/zcalcd for C₂₄H₂₀N₂O₃F [M + H⁺] 403.1458, found 403.1458.

SYNTHERSIS

Setipiprant (INN) (developmental code names ACT-129,968, KYTH-105) is a drug originally developed by Actelion which acts as a selective, orally available antagonist of the prostaglandin D₂ receptor 2 (DP₂).^[1] It was initially researched as a treatment for allergies and inflammatory disorders, particularly asthma, but despite being well tolerated in clinical trials and showing reasonable efficacy against allergen-induced airway responses in asthmatic patients,^[2]^[3] it failed to show sufficient advantages over existing drugs and was discontinued from further development in this application.^[4]

However, following the discovery in 2012 that the prostaglandin D₂ receptor (DP/PGD₂) is expressed at high levels in the scalp of men affected by male pattern baldness,^[5] the rights to setipiprant were acquired by Kythera with a view to potentially developing this drug as a novel treatment for baldness, with a previously unexploited mechanism of action.^[6] While it is too early to tell whether setipiprant will be an effective treatment for this condition, the favorable pharmacokinetics and relative lack of side effects seen in earlier clinical trials mean that fresh clinical trials for this new application can be conducted fairly quickly.^[7]

Prostaglandin D2 is a known agonist of the thromboxane A2 (TxA2) receptor, the PGD2 (DP) receptor and the recently identified G-protein-coupled “chemoattractant receptor- homologous molecule expressed on Th2 cells” (CRTH2).

The response to allergen exposure in a previously sensitized host results in a cascade effect involving numerous cell types and release of a number of cytokines, chemokines, and multiple mediators. Among these critical initiators are the cytokines interleukin (IL)-4, IL-13, and IL-5, which play critical roles in Th2 cell differentiation, immunoglobulin (Ig)E synthesis, mast cell growth and differentiation, upregulation of CD23 expression, and the differentiation, recruitment, and activation of eosinophils. The stimulated release of the array of mediators, causes end-organ damage, including constriction and hyperresponsi- veness, vascular permeability, edema, mucous secretion, and further inflammation.

Because of the number of responses targeted, corticosteroids have proven to be the most effective therapy. Rather than antagonizing these specific responses in a directed way, another approach is to alter the immune response, that is, to change the nature of the immunological response to allergen. CRTH2 is preferentially expressed on Th2 cells and is a chemoattractant receptor for PGD2 that mediates PGD2-dependent migration of blood Th2 cells. Chemoattractants are responsible for the recruitment of both Th2 cells and other effector cells of allergic inflammation, which can provide the conceptual basis for the development of new therapeutic strategies in allergic conditions.

So far, few compounds having CRTH2 antagonistic activity have been reported in the patent literature. Bayer AG claims the use of Ramatroban ((3R)-3-(4-fluorobenzene- sulfonamido)-l,2,3,4-tetrahydrocarbazole-9-propionic acid) for the prophylaxis and treatment of allergic diseases, such as asthma, allergic rhinitis or allergic conjuvatitis

(GB 2388540). Further, (2-tert.-butoxycarbonyl-l, 2, 3, 4-tetrahydro-pyrido[4,3-b]indol-5- yl)-acetic acid and (2-ethoxycarbonyl-l, 2, 3, 4-tetrahydro-pyrido[4,3-b]indol~5-yl)-acetic acid are disclosed by Kyle F. et al in two patent applications (US 5817756 and WO 9507294, respectively).

Furthermore, oral bioavailability of the Ramatroban and its ability to inhibit prostaglandin D2-induced eosinophil migration in vitro has been reported (Journal of Pharmacology and Experimental Therapeutics, 305(1), p.347-352 (2003)).

Description of the invention:

It has now been found that compounds of the general Formulae (I) and (II) of the present invention are CRTH2 receptor antagonists. These compounds are useful for the treatment of both chronic and acute allergic/immune disorders such as allergic asthma, rhinitis, chronic obstructive pulmonary disease (COPD), dermatitis, inflammatory bowel disease, rheumatoid arthritis, allergic nephritis, conjunctivitis, atopic dermatitis, bronchial asthma, food allergy, systemic mast cell disorders, anaphylactic shock, urticaria, eczema, itching, inflammation, ischemia-reperfusion injury, cerebrovascular disorders, pleuritis, ulcerative colitis, eosinophil-related diseases, such as Churg-Strauss syndrome and sinusitis, basophil- related diseases, such as basophilic leukemia and basophilic leukocytosis.

The compounds of general Formulae (I) and (II), especially those mentioned as being preferred, display high selectivity towards the CRTH2 receptor. No antagonistic effects (IC₅₀ >10 μM) are observed on e.g. prostaglandin D2 receptor DPI; PGI2 receptor (IP), PGE2 receptors (EPl, EP2, EP3, EP4), PGF2 receptor (FP), thromboxane receptor A2 (TxA2), leukotriene receptors (CysLTl, CysLT2, LTB4), complement receptor (C5a), angiotensin receptors (ATI, AT2) or serotonin receptor 5HT2c.

The solubility of compounds of general Formulae (I) and (II) in buffer at pH 7 is generally >800 μg/ml.

In vitro assays with rat and dog liver microsomes, or with rat and human hepatocytes revealed high metabolic stability for compounds of general Foπnulae (I) and (II), especially for those compounds mentioned as being preferred.

The compounds of general Formulae (I) and (II), especially those mentioned as being preferred, do not interfere with cytochrome P-450 enzymes, e.g. they are neither degraded by, nor do they inhibit such enzymes.

Excellent pharmacokinetic profiles have been observed for compounds of general Formulae (I) and (II), especially for those compounds mentioned as being preferred, after oral administration (10 mg/kg) to rats and dogs (bioavailability 20-80%, T_max 30 min, C_max 2000- 6000 ng/ml, low clearance, T_{] 2}4-8 h). The compounds of general Formulae (I) and (II), especially those mentioned as being preferred, are efficacious in vitro, inhibiting PGD2-induced migration of eosinophils or other CRTH2 expressing cells in a cell migration assay. A number of techniques have been developed to assay such chemotactic migration (see, e.g., Leonard et al., 1995, “Measurement of α- and β-Chemokines”, in Current Protocols in Immunology, 6.12.1- 6.12.28, Ed. Coligan et al, John Wiley & Sons, Inc. 1995). The compounds of the present invention are tested using a protocol according to H. Sugimoto et al. (J Pharmacol Exp Ther. 2003, 305(1), 347-52), or as described hereinafter: Purified eosinophils are labeled with a fluorescent dye, i.e. Calcein-AM and loaded in BD Falcon FluoroBlock upper inserts. Test compounds are diluted and incubated with eosinophils in the BD Falcon

FluoroBlock upper inserts for 30 min at 37 °C in a humidified CO₂ incubator. A constant amount of PGD2 is added to BD Falcon FluoroBlock lower chamber, at a concentration known to have a chemotactic effect on CRTH2 cells. As a control, at least one aliquot in the upper well does not contain test compound. The inserts are combined with the chambers and are incubated for 30 min at 37 °C in a humidified CO₂ incubator. After an incubation period, the number of migrating cells on the lower chamber is counted using a fluorescent reader, i.e. an Applied Biosystems Cyto Fluor 4000 plate reader. The contribution of a test compound to the chemotactic activity of PGD2 is measured by comparing the chemotactic activity of the aliquots containing only dilution buffer with the activity of aliquots containing a test compound. If addition of the test compound to the solution results in a decrease in the number of cells detected in the lower chamber relative to the number of cells detected using a solution containing only PGD2, then there is identified an antagonist of PGD2 induction of chemotactic activity of eosinophils.

PAPER

Journal of Medicinal Chemistry (2013), 56(12), 4899-4911

http://pubs.acs.org/doi/abs/10.1021/jm400122f

Identification of 2-(2-(1-Naphthoyl)-8-fluoro-3,4-dihydro-1H-pyrido[4,3-b]indol-5(2H)-yl)acetic Acid (Setipiprant/ACT-129968), a Potent, Selective, and Orally Bioavailable Chemoattractant Receptor-Homologous Molecule Expressed on Th2 Cells (CRTH2) Antagonist

Heinz Fretz*, Anja Valdenaire, Julien Pothier, Kurt Hilpert, Carmela Gnerre, Oliver Peter, Xavier Leroy, and Markus A. Riederer

Drug Discovery Unit, Actelion Pharmaceuticals Ltd., Gewerbestrasse 16, CH-4123 Allschwil, Switzerland

J. Med. Chem., 2013, 56 (12), pp 4899–4911

DOI: 10.1021/jm400122f

Herein we describe the discovery of the novel CRTh2 antagonist 2-(2-(1-naphthoyl)-8-fluoro-3,4-dihydro-1H-pyrido[4,3-b]indol-5(2H)-yl)acetic acid 28 (setipiprant/ACT-129968), a clinical development candidate for the treatment of asthma and seasonal allergic rhinitis. A lead optimization program was started based on the discovery of the recently disclosed CRTh2 antagonist 2-(2-benzoyl-3,4-dihydro-1H-pyrido[4,3-b]indol-5(2H)-yl)acetic acid 5. An already favorable and druglike profile could be assessed for lead compound 5. Therefore, the lead optimization program mainly focused on the improvement in potency and oral bioavailability. Data of newly synthesized analogs were collected from in vitro pharmacological, physicochemical, in vitro ADME, and in vivo pharmacokinetic studies in the rat and the dog. The data were then analyzed using a traffic light selection tool as a visualization device in order to evaluate and prioritize candidates displaying a balanced overall profile. This data-driven process and the excellent results of the PK study in the rat (F = 44%) and the dog (F = 55%) facilitated the identification of 28 as a potent (IC₅₀ = 6 nM), selective, and orally available CRTh2 antagonist.

PAtent

WO 2005095397

http://www.google.co.in/patents/WO2005095397A1?cl=en

Formula 6.

Scheme 1

Step a)

Step b)

Scheme 2

Formula (I).

References

Fretz H, Valdenaire A, Pothier J, Hilpert K, Gnerre C, Peter O, Leroy X, Riederer MA. Identification of 2-(2-(1-naphthoyl)-8-fluoro-3,4-dihydro-1H-pyrido[4,3-b]indol-5(2H)-yl)acetic acid (setipiprant/ACT-129968), a potent, selective, and orally bioavailable chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2) antagonist. J Med Chem. 2013 Jun 27;56(12):4899-911. doi: 10.1021/jm400122f PMID 23721423
Sidharta PN, Diamant Z, Dingemanse J. Single- and multiple-dose tolerability and pharmacokinetics of the CRTH2 antagonist setipiprant in healthy male subjects. Fundam Clin Pharmacol. 2014 Dec;28(6):690-9. doi: 10.1111/fcp.12079 PMID 24734908
Diamant Z, Sidharta PN, Singh D, O’Connor BJ, Zuiker R, Leaker BR, Silkey M, Dingemanse J. Setipiprant, a selective CRTH2 antagonist, reduces allergen-induced airway responses in allergic asthmatics. Clin Exp Allergy. 2014 Aug;44(8):1044-52. doi: 10.1111/cea.12357 PMID 24964348
Norman P. Update on the status of DP2 receptor antagonists; from proof of concept through clinical failures to promising new drugs. Expert Opin Investig Drugs. 2014 Jan;23(1):55-66. doi: 10.1517/13543784.2013.839658 PMID 24073896
Garza LA, et al. Prostaglandin D2 inhibits hair growth and is elevated in bald scalp of men with androgenetic alopecia. Science Translational Medicine, 21 March 2012; 4(126):126ra34. doi: 10.1126/scitranslmed.3003122
George Cotsarelis, Garret Fitzgerald, Luis Garza. Compositions and methods for regulating hair growth. US Patent application 2015/0072963
Pipeline KYTH-105 (setipiprant)
http://files.shareholder.com/downloads/AMDA-MFNLA/4023632629x0x817836/4E5AC47A-B9EE-4296-9D97-631C0F6B7C97/KYTH-105_setipiprant_.pdf

Patent ID	Date	Patent Title
US2015072963	2015-03-12	COMPOSITIONS AND METHODS FOR REGULATING HAIR GROWTH
US2014328861	2014-11-06	Combination of CRTH2 Antagonist and a Proton Pump Inhibitor for the Treatment of Eosinophilic Esophagitis
US2010234396	2010-09-16	Tetrhydropyridoindole Derivatives
US7714132	2010-05-11	Tetrahydropyridoindole derivatives

S etipiprant
Systematic (IUPAC) name

2-[8-fluoro-2-(naphthalene-1-carbonyl)-3,4-dihydro-1H-pyrido[4,3-b]indol-5-yl]acetic acid
Clinical data
Administration	Oral
Identifiers
CASRN	866460-33-5
ATC code	none
PubChem	CID 49843471
Chemical data
Formula	C₂₄H₁₉FN₂O₃
Molar mass	402.417 g/mol

///////Setipiprant, KYTH-105, 866460-33-5, ALLERGAN, Alopecia, KYTHERA

c15ccccc5cccc1C(=O)N(CC3)Cc2c3n(CC(O)=O)c(cc4)c2cc4F

Crisil rings warning bell for pharma on US slowdown

regulatory Comments Off

May 262016

Companies like Dr. Reddy’s Laboratories and Sun Pharma derive close to 60% of their revenue from exports to the US. Lupin too, gets 45% of its revenue from generic formulation sales to the US, while others like Cadila Healthcare, Torrent Pharma ……………

Crisil rings warning bell for pharma on US slowdown

////Crisil, warning bell, pharma, US slowdown

EU GMP Annex 1 Revision 2016 – what does the pharmaceutical industry expect?

regulatory Comments Off

May 262016

Dr Friedrich Haefele, Vice President Fill & Finish Biopharma at Boehringer Ingelheim

Dr Friedrich Haefele, Vice President Fill & Finish Biopharma at Boehringer Ingelheim talked in his keynote speech at the Pharma Congress 2016 about the revision of Annex 1 of the EU GMP Guide. Read here what the pharmaceutical industry expects form the new Annex 1.

http://www.gmp-compliance.org/enews_05326_EU-GMP-Annex-1-Revision-2016—what-does-the-pharmaceutical-industry-expect_15160,15266,15265,15432,Z-PEM_n.html

Europe’s biggest Pharma Congress of its kind took place in Düsseldorf on 12 and 13 April. With more than 1000 participants, 90 exhibitors and 10 GMP conferences this Congress 2016 has been the biggest since the first one 18 years ago. 50 lectures, almost exclusively case studies from pharmacuetical companies such as Pfizer, Novartis, Boehringer Ingelheim and many more were discussed. Special attention was paid to the keynotes at the beginning of each congress day.

Dr Friedrich Haefele, Vice President Fill & Finish Biopharma at Boehringer Ingelheim talked in his keynote speech about the revision of Annex 1 of the EU Guidelines to Good Manufacturing Practice. The first version dates already back to the year 1972. Dr Haefele stated that there had already been five revisions since this time but no fundamental review. This means the time has come to revise this fundamental document on the regulation of sterile manufacture in Europe.

Dr Haefele demonstrated the need for action on one hand by a comparison with the FDA Aseptic Guide and on the other hand by means of his own commenting. Friedrich Haefele said that priority should be given to harmonisation. He basically believes that Annex 1 should remain reserved for sterile parenteral products and that other sterile products or active pharmaceutical ingredients should be regulated in other documents or in specific annexes. He also wants a separation between aseptically manufactured and terminally sterilised products in the new Annex 1.

He considers DIN ISO 14644-1 to be a central document that is used for the classification of clean rooms in the European Guideline but also in the US Guide. Dr Haefele is not bothered by the fact that the limit for 5 µm particles has been deleted from the grade ISO 5 (ISO 4.8). According to him it should also be deleted from the European requirements. Deviations in the case of 0.5 and 5 µm particles occur essentially in parallel so that it should be possible to renounce to the limit for 5 µm particles.

Dr Haefele also proposed a simplification for the microbiological environmental monitoring. Settle plates as well as microbial air sampling are required in Europe at the moment. According to Dr Haefele only the microbial air sampling should be compulsory whereas the use of settle plates should be optional or additional. The use of average values in the microbiological monitoring in the clean room should be dismissed. With the use of isolators with validated decontamination cycles the microbiological monitoring could be reduced to the essential pursuant to ICH Q9 Quality Risk Management.

In contrast to the FDA Aseptic Guide the European Annex 1 contains requirements concerning the crimping process as well as a differentiation between aseptic and clean processes. For the latter Dr Haefele wants a clear definition of “Grade A Air Supply” that should be used for protection during the process according to Annex 1. Dr Haefele stated that the industry has its opinion concerning this but that it should also be recorded in the relevant official document. By this he meant the use of air filtered according to the requirements of grade A without considering the microbiological requirements.

There are important differences between Annex 1 and the Aseptic Guide in the area of sterilisation. The US document contains no indications for a terminal product sterilisation. It is contained in the EU document. Dr Haefele proposes to limit the requirement for a sterilisation with pure steam primariliy to the terminal product sterilisation and to also allow other methods e.g. sterilisation with ethylene oxide for example for so-called ready-to-use materials.

He sees further potential for improvement concerning the topic sterile filtration. He considers that the integrity testing after sterilisation immediately before filling can be omitted since the data of the filter validation and the integrity testing after filling give adequate security. To renounce to the obligatory integrity testing after sterilisation and before use, reduces the complexity of the aseptic set-up and when constructing facilities.

A further difference concerns the quality oversight. In Europe there is no requirement that the quality assurance (physically) must take place on-site during aseptic processes. But the Aseptic Guide requires a QC oversight and here, especially the media fill is mentioned. Dr Haefele invoked a harmonisation of the requirements, in order to strengthen the European philosophy, however. Quality assurance is a system and not an organisation. Mr. Haefele proposed a further change concerning the media fill in isolators. Here, interventions are carried out from the outside when carrying gloves. This means that they are “person-neutral”. The requirement that the qualification of interventions during the media fill has to be done person-specific should therefore be omitted for media fills in isolators.

As concerns the topic disinfection Mr. Haefele would prefer the admission of hydrogen peroxide for the decontamination of surfaces in isolators and material locks as well as the dispensation with the mandatory rotation when using disinfectants.
A further topic in Annex 1 is the monitoring of the integrity of containers containing sterile medicinal products. At the moment, the Annex requires a 100% integrity testing only for containers closed by fusion (glass ampoules and BFS containers). Dr Haefele would prefer more openness up to suitable controls for all packaging systems or pharmaceutical dosage forms.

Finally, he reaffirmed the use of modern barrier techniques for the aseptic manufacture as state-of-the-art and repeated his wish for a harmonisation of the requirements for sterile and aseptically produced medicinal products. MRA, mutual recognition agreements, could reduce the number of regulatory inspections at the companies.

Currently, the publication of the draft of the new EU GMP Annex 1 is planned for autumn 2016.

Source: Pharma Kongress 2016 (companies who wish to book a booth in 2017 can register here)
/////Dr Friedrich Haefele, Vice President, Fill & Finish Biopharma, Boehringer Ingelheim, EU GMP Annex 1 Revision 2016, pharmaceutical industry,

WHO issues revised Guideline on HVAC Systems

regulatory Comments Off

May 262016

The World Health Organization (WHO) recently issued a guideline for commenting which describes the requirements for HVAC systems for the manufacture of non-sterile forms. As most guidelines on this topic address the requirements for sterile dosage forms, the previous version was gladly accepted by industry. Learn more about the revised guideline on HVAC systems.

http://www.gmp-compliance.org/enews_05358_WHO-issues-revised-Guideline-on-HVAC-Systems_15160,15221,15661,15612,Z-PEM_n.html

The World Health Organization (WHO) recently issued a guideline for commenting which describes the requirements for HVAC systems used for the manufacture of non-sterile dosage forms. As most guidelines on this topic address the requirements for sterile forms, the previous version (TRS 961, Annex 1) from 2011 was gladly accepted by industry. Mentioned are non-sterile dosage forms as tablets, capsules, liquids or ointments, but also for the final steps in the manufacture of APIs. The WHO guideline means to provide guidance specifically for the areas design, installation, qualification and maintenance of ventilation systems. For the manufacture of highly potent materials the WHO refers to their Guideline TRS 961, Annex 3.

The biggest changes comprise:

The chapter “Premises” was moved to the front to emphasize its importance. The chapter now further comprises some sample layouts
The section “Commissioning, Qualification and Validation” was revised to match it with the WHO Guideline TRS 937, Annex 4 (Supplementary guidelines on good manufacturing practices: validation)
The part “Maintenance” was removed from the part “Commissioning, Qualification and Validation” and is now a separte chapter
In addition a number of comments were added, graphs revised, and the overall readability was improved

Due to the many references and the numerous and improved illustrations the document is a good source for the (exemplary) requirements in the manufacture of solid and non-sterile dosage forms.

To find out more please visit the WHO website where you will find the draft document SUPPLEMENTARY GUIDELINES ON GOOD MANUFACTURING PRACTICES FOR HEATING, VENTILATION AND AIR-CONDITIONING SYSTEMS FOR NON-STERILE PHARMACEUTICAL DOSAGE FORMS. The deadline for comments is the 12 July 2016. The results are expected to be discussed during the 51st WHO expert committee meeting in October.

///////////WHO, revised Guideline, HVAC Systems