(Z and E)-4-(Methylamino)-3-(4-nitrobenzoyl)-2-oxobut-3-enoic Acid Ethyl Ester

Uncategorized Comments Off

Feb 232018

(Z and E)-4-(Methylamino)-3-(4-nitrobenzoyl)-2-oxobut-3-enoic Acid Ethyl Ester (2a)

Light yellow solid; yield: 0.276 g (90%); Z/E ratio in CDCl₃: 80/20; mp 143.8–145.3 °C;

¹H NMR (300.06 MHz, CDCl₃) δ (ppm) (Z) 1.29 (t, 3H, J = 7.2 Hz, O–CH₂–CH₃), 3.24 (dd, 3H, J = 5.2, 0.7 Hz, NH-CH₃), 4.17 (q, 2H, J = 7.2 Hz, O–CH₂-CH₃), 7.64 (dd, 1H, J = 14.1, 0.7 Hz, H4), 7.75 (d, 2H, J = 8.8 Hz, 4-NO₂C₆H₄), 8.28 (d, 2H, J = 8.9 Hz, 4-NO₂C₆H₄), 10.67 (bs, 1H, NH); (E) 1.14 (t, 3H, J = 7.2 Hz, O–CH₂–CH₃), 3.34 (dd, 3H, J = 5.2, 0.8 Hz, NH-CH₃), 3.81 (q, 2H, J = 7.2 Hz, O–CH₂-CH₃), 7.62 (d, 2H, J = 8.8 Hz, 4-NO₂C₆H₄), 8.20 (dd, 1H, J = 14.3, 0.8 Hz, H4), 8.23 (d, 2H, J= 8.8 Hz, 4-NO₂C₆H₄), 10.79 (bs, 1H, NH);

¹³C NMR (75.46 MHz, CDCl₃) δ (ppm) (Z) 13.9 (O–CH₂–CH₃), 37.2 (NH-CH₃), 61.8 (O-CH₂–CH₃), 107.0 (C3), 123.7, 129.5, 144.5, 149.2 (4-NO₂C₆H₄), 163.1 (C4), 164.9 (COOEt), 186.9 (C2), 190.8 (C3′); (E) 13.7 (O–CH₂–CH₃), 37.1 (NH-CH₃), 62.0 (O-CH₂–CH₃), 106.7 (C3), 123.4, 128.6, 146.4, 148.8 (4-NO₂C₆H₄), 163.3 (C4), 164.4 (COOEt), 183.3 (C2), 193.7 (C3′);

HRMS (ESI+): calcd for C₁₄H₁₅N₂O₆⁺, [M+H]⁺: 307.0925, found 307.0938.

J. Org. Chem., 2017, 82 (23), pp 12590–12602

DOI: 10.1021/acs.joc.7b02361

//////////////https://pubs.acs.org/doi/abs/10.1021/acs.joc.7b02361

Pfizer’s monobactam PF-?

PRECLINICAL, Uncategorized Comments Off

Feb 232018

Pfizer’s monobactam PF-?

1380110-34-8, C₂₀ H₂₄ N₈ O₁₂ S_2, 632.58

Propanoic acid, 2-[[(Z)-[1-(2-amino-4-thiazolyl)-2-[[(2R,3S)-2-[[[[[(1,4-dihydro-1,5-dihydroxy-4-oxo-2-pyridinyl)methyl]amino]carbonyl]amino]methyl]-4-oxo-1-sulfo-3-azetidinyl]amino]-2-oxoethylidene]amino]oxy]-2-methyl-

2-((Z)-1-(2-Aminothiazol-4-yl)-2-((2R,3S)-2-((((1,5-dihydroxy-4-oxo-1,4-dihydropyridin-2-yl)methoxy)carbonylamino)methyl)-4-oxo-1-sulfoazetidin-3-ylamino)-2-oxoethylideneaminooxy)-2-methylpropanoic Acid

2-[[(Z)-[1-(2-Amino-4-thiazolyl)-2-[[(2R,3S)-2-[[[[[(1,4-dihydro-1,5-dihydroxy-4-oxo-2-pyridinyl)methyl]amino]carbonyl]amino]methyl]-4-oxo-1-sulfo-3-azetidinyl]amino]-2-oxoethylidene]amino]oxy]-2-methylpropanoic acid

Monobactams are a class of antibacterial agents which contain a monocyclic beta-lactam ring as opposed to a beta-lactam fused to an additional ring which is found in other beta-lactam classes, such as cephalosporins, carbapenems and penicillins. The drug Aztreonam is an example of a marketed monobactam; Carumonam is another example. The early studies in this area were conducted by workers at the Squibb Institute for Medical Research, Cimarusti, C. M. & R.B. Sykes: Monocyclic β-lactam antibiotics. Med. Res. Rev. 1984, 4, 1 -24. Despite the fact that selected

monobacatams were discovered over 25 years ago, there remains a continuing need for new antibiotics to counter the growing number of resistant organisms.

Although not limiting to the present invention, it is believed that monobactams of the present invention exploit the iron uptake mechanism in bacteria through the use of siderophore-monobactam conjugates. For background information, see: M. J. Miller, et al. BioMetals (2009), 22(1 ), 61-75.

The mechanism of action of beta-lactam antibiotics, including monobactams, is generally known to those skilled in the art and involves inhibition of one or more penicillin binding proteins (PBPs), although the present invention is not bound or limited by any theory. PBPs are involved in the synthesis of peptidoglycan, which is a major component of bacterial cell walls.

WO 2012073138

https://www.google.com/patents/WO2012073138A1?cl=en

Inventors	Matthew Frank Brown, Seungil Han, Manjinder Lall, Mark. J. Mitton-Fry, Mark Stephen Plummer, Hud Lawrence Risley, Veerabahu Shanmugasundaram, Jeremy T. Starr,
Applicant	Pfizer Inc.

Example 4, Route 1

2-({[(1Z)-1 -(2-amino-1 ,3-thiazol-4-yl)-2-({(2f?,3S)-2-[({[(1 ,5-dihydroxy-4-oxo-1 ,4- dihydropyridin-2-yl)methyl]carbamoyl}amino)methyl]-4-oxo-1 -sulfoazetidin-3- yl}amino)-2-oxoethylidene]amino}oxy)-2-methylpropanoic acid, bis sodium salt

(C92-Bis Na Salt).

C92-bis Na salt

Step 1 : Preparation of C90. A solution of C26 (16.2 g, 43.0 mmol) in tetrahydrofuran (900 mL) was treated with 1 , 1 ‘-carbonyldiimidazole (8.0 g, 47.7 mmol). After 5 minutes, the reaction mixture was treated with a solution of C9 (15 g, 25.0 mmol) in anhydrous tetrahydrofuran (600 mL) at room temperature. After 15 hours, the solvent was removed and the residue was treated with ethyl acetate (500 mL) and water (500 mL). The layers were separated and the aqueous layer was back extracted with additional ethyl acetate (300 mL). The organic layers were combined, washed with brine solution (500 mL), dried over sodium sulfate, filtered and concentrated in vacuo. The crude product was purified via chromatography on silica gel (ethyl acetate / 2-propanol) to yield C90 as a yellow foam. Yield: 17.44 g, 19.62 mmol, 78%. LCMS m/z 889.5 (M+1 ). ¹H NMR (400 MHz, DMSO-d₆) 1 1 .90 (br s, 1 H), 9.25 (d, J=8.7 Hz, 1 H), 8.40 (br s, 1 H), 7.98 (s, 1 H), 7.50-7.54 (m, 2H), 7.32-7.47 (m, 8H), 7.28 (s, 1 H), 6.65 (br s, 1 H), 6.28 (br s, 1 H), 5.97 (s, 1 H), 5.25 (s, 2H), 5.18 (dd, J=8.8, 5 Hz, 1 H), 4.99 (s, 2H), 4.16-4.28 (m, 2H), 3.74-3.80 (m, 1 H), 3.29-3.41 (m, 1 H), 3.13-3.23 (m, 1 H), 1.42 (s, 9H), 1.41 (s, 3H), 1.39 (br s, 12H).

Step 2: Preparation of C91. A solution of C90 (8.5 g, 9.6 mmol) in anhydrous N,N- dimethylformamide (100 mL) was treated sulfur trioxide /V,/V-dimethylformamide complex (15.0 g, 98.0 mmol). The reaction was allowed to stir at room temperature for 20 minutes then quenched with water (300 mL). The resulting solid was collected by filtration and dried to yield C91 as a white solid. Yield: 8.1 g, 8.3 mmol, 87%. LCMS m/z 967.6 (M-1 ). ¹H NMR (400 MHz, DMSO-d₆) δ 1 1.62 (br s, 1 H), 9.29 (d, J=8.8 Hz, 1 H), 9.02 (s, 1 H), 7.58-7.61 (m, 2H), 7.38-7.53 (m, 9H), 7.27 (s, 1 H), 7.07 (s, 1 H), 6.40 (br d, J=8 Hz, 1 H), 5.55 (s, 2H), 5.25 (s, 2H), 5.20 (dd, J=8.8, 5.6 Hz, 1 H), 4.46 (br dd, half of ABX pattern, J=17, 5 Hz, 1 H), 4.38 (br dd, half of ABX pattern, J=17, 6 Hz, 1 H), 3.92-3.98 (m, 1 H), 3.79-3.87 (m, 1 H), 3.07-3.17 (m, 1 H), 1.40 (s, 9H), 1 .39 (s, 3H), 1 .38 (s, 12H).

Step 3: Preparation of C92. A solution of C91 (8.1 g, 8.3 mmol) in anhydrous dichloromethane (200 mL) was treated with 1 M boron trichloride in p-xylenes (58.4 mL, 58.4 mmol) and allowed to stir at room temperature for 15 minutes. The reaction mixture was cooled in an ice bath, quenched with 2,2,2-trifluoroethanol (61 mL), and the solvent was removed in vacuo. A portion of the crude product (1 g) was purified via reverse phase chromatography (C-18 column; acetonitrile / water gradient with 0.1 % formic acid modifier) to yield C92 as a white solid. Yield: 486 mg, 0.77 mmol. LCMS m/z 633.3 (M+1 ). ¹H NMR (400 MHz, DMSO-d₆) δ 9.22 (d, J=8.7 Hz, 1 H), 8.15 (s, 1 H), 7.26-7.42 (br s, 2H), 7.18-7.25 (m, 1 H), 6.99 (s, 1 H), 6.74 (s, 1 H), 6.32-6.37 (m, 1 H), 5.18 (dd, J=8.7, 5.7 Hz, 1 H), 4.33 (br d, J=4.6 Hz, 2H), 3.94-4.00 (m, 1 H), 3.60-3.68 (m, 1 H), 3.19-3.27 (m, 1 H), 1.40 (s, 3H), 1.39 (s, 3H).

Step 4: Preparation of C92-Bis Na Salt. A flask was charged with C92 (388 mg, 0.61 mmol) and water (5.0 mL). The mixture was cooled in an ice bath and treated dropwise with a solution of sodium bicarbonate (103 mg, 1.52 mmol) in water (5.0 mL). The sample was lyophilized to yield C92-Bis Na Salt as a white solid. Yield: 415 mg, 0.61 mmol, quantitative. LCMS m/z 633.5 (M+1 ). ¹H NMR (400 MHz, D₂0) δ 7.80 (s, 1 H), 6.93 (s, 1 H), 6.76 (s, 1 H), 5.33 (d, J=5.7 Hz, 1 H), 4.44 (ddd, J=6.0, 6.0, 5.7 Hz, 1 H), 4.34 (AB quartet, J_AB=17.7 Hz, Δν_ΑΒ=10.9 Hz, 2H), 3.69 (dd, half of ABX pattern, J=14.7, 5.8 Hz, 1 H), 3.58 (dd, half of ABX pattern, J=14.7, 6.2 Hz, 1 H), 1.44 (s, 3H), 1.43 (s, 3H).

Alternate preparation of C92

Step 1 : Preparation of C93. An Atlantis pressure reactor was charged with 10% palladium hydroxide on carbon (0.375 g, John Matthey catalyst type A402028-10), C91 (0.75 g, 0.77 mmol) and treated with ethanol (35 mL). The reactor was flushed with nitrogen and pressurized with hydrogen (20 psi) for 20 hours at 20 °C. The reaction mixture was filtered under vacuum and the filtrate was concentrated using the rotary evaporator to yield C93 as a tan solid. Yield: 0.49 g, 0.62 mmol, 80%. LCMS m/z 787.6 (M-1 ). ¹H NMR (400 MHz, DMSO-d₆) δ 1 1.57 (br s, 1 H), 9.27 (d, J=8.5 Hz, 1 H), 8.16 (s, 1 H), 7.36 (br s, 1 H), 7.26 (s, 1 H), 7.00 (s, 1 H), 6.40 (br s, 1 H), 5.18 (m, 1 H), 4.35 (m, 2H), 3.83 (m, 1 H), 3.41 (m, 1 H), 3.10 (m, 1 H), 1.41 (s, 6H), 1.36 (s, 18H).

Step 2: Preparation of C92. A solution of C93 (6.0 g, 7.6 mmol) in anhydrous dichloromethane (45 mL) at 0 °C was treated with trifluoroacetic acid (35.0 mL, 456 mmol). The mixture was warmed to room temperature and stirred for 2 hours. The reaction mixture was cannulated into a solution of methyl ferf-butyl ether (100 mL) and heptane (200 mL). The solid was collected by filtration and washed with a mixture of methyl ferf-butyl ether (100 mL) and heptane (200 mL) then dried under vacuum. The crude product (~5 g) was purified via reverse phase chromatography (C-18 column; acetonitrile / water gradient with 0.1 % formic acid modifier) and lyophilized to yield C92 as a pink solid. Yield: 1.45 g, 2.29 mmol. LCMS m/z 631.0 (M-1). ¹H NMR (400 MHz, DMSO-de) δ 9.20 (d, J=8.7 Hz, 1H), 8.13 (s, 1H), 7.24-7.40 (br s, 2H), 7.16-7.23 (m, 1H), 6.97 (s, 1H), 6.71 (s, 1H), 6.31-6.35 (m, 1H), 5.15 (dd, J=8.7, 5.7 Hz, 1H), 4.31 (br d, J=4.6 Hz, 2H), 3.92-3.98 (m, 1H), 3.58-3.67 (m, 1H), 3.17-3.25 (m, 1H), 1.37 (s, 3H), 1.36 (s, 3H).

Example 4, route 2

2-({[(1Z)-1-(2-amino-1,3-thiazol-4-yl)-2-({(2 ?,3S)-2-[({[(1,5-dihydroxy-4-oxo-^ dihydropyridin-2-yl)methyl]carbamoyl}amino)methyl]-4-oxo-1-sulfoazetidin-3- yl}amino)-2-oxoethylidene]amino}oxy)-2-methylpropanoic acid (C92).

single

enantiomer

Step 1. Preparation of C95. A solution of C94 (50.0 g, 189.9 mmol) in

dichloromethane (100 mL) was treated with trifluoroacetic acid (50.0 mL, 661.3 mmol). The reaction mixture was stirred at room temperature for 24 hours. The dichloromethane and trifluoroacetic acid was displaced with toluene (4 x 150 mL) using vacuum, to a final volume of 120 mL. The solution was added to heptane (250 mL) and the solid was collected by filtration. The solid was washed with a mixture of toluene and heptane (1 : 3, 60 mL), followed by heptane (2 x 80 mL) and dried under vacuum at 50 °C for 19 hours to afford C95 as a solid. Yield: 30.0 g, 158 mmol, 84%. ¹H NMR (400 MHz, CDCI3) δ 9.66 (s, 1 H), 7.86 – 7.93 (m, 2H), 7.73 – 7.80 (m, 2H), 4.57 (s, 2H). HPLC retention time 5.1 minutes; column: Agilent Extended C-18 column (75 mm x 3 mm, 3.5 μηη); column temperature 45 °C; flow rate 1.0 mL / minute; detection UV 230 nm; mobile phase: solvent A = acetonitrile (100%), solvent B = acetonitrile (5%) in 10 mM ammonium acetate; gradient elusion: 0-1.5 minutes solvent B (100%), 1.5-10.0 minutes solvent B (5%), 10.0-13.0 minutes solvent B (100%); total run time 13.0 minutes.

Step 2: Preparation of C96-racemic. A solution of C95 (32.75 g; 173.1 mmol) in dichloromethane (550 mL) under nitrogen was cooled to 2 °C. The solution was treated with 2,4-dimethoxybenzylamine (28.94 g, 173.1 mmol) added dropwise over 25 minutes, maintaining the temperature below 10 °C. The solution was stirred for 10 minutes at 2 °C and then treated with molecular sieves (58.36 g, UOP Type 3A). The cold bath was removed and the reaction slurry was stirred for 3 hours at room temperature. The slurry was filtered through a pad of Celite (34.5 g) and the filter cake was rinsed with dichloromethane (135 mL). The dichloromethane filtrate (imine solution) was used directly in the following procedure.

A solution of A/-(ferf-butoxycarbonyl)glycine (60.6 g, 346.1 mmol) in

tetrahydrofuran (622 mL) under nitrogen was cooled to -45 °C and treated with triethylamine (38.5 g, 380.8 mmol). The mixture was stirred for 15 minutes at -45 °C and then treated with ethyl chloroformate (48.8 g, 450 mmol) over 15 minutes. The reaction mixture was stirred at -50 °C for 7 hours. The previously prepared imine solution was added via an addition funnel over 25 minutes while maintaining the reaction mixture temperature below -40 °C. The slurry was treated with triethylamine (17.5 g, 173 mmol) and the reaction mixture was slowly warmed to room temperature over 5 hours and stirred for an additional 12 hours. The reaction slurry was charged with water (150 mL) and the volatiles removed using a rotary evaporator. The reaction mixture was charged with additional water (393 mL) and the volatiles removed using a rotary evaporator. The mixture was treated with methyl ferf-butyl ether (393 mL) and vigorously stirred for 1 hour. The solid was collected by vacuum filtration and the filter cake was rinsed with a mixture of methyl ferf-butyl ether and water (1 : 1 , 400 mL). The solid was collected and dried in a vacuum oven at 50 °C for 16 hours to afford C96- racemic. Yield: 55.8 g, 1 13 mmol, 65%. ¹H-NMR (400 MHz, DMSO-d₆) δ 7.85 (s, NH), 7.80 (s, 4H), 6.78 (d, J=7.8 Hz, 1 H), 6.25 (m, 1 H), 6.10 (m, 1 H), 4.83 (m, 1 H), 4.38 (d, J=9.5 Hz, 1 H), 3.77-3.95 (m, 3H), 3.62 (s, 3H), 3.45 (m, 1 H), 3.40 (s, 3H), 1.38 (s, 9H). HPLC retention time 6.05 minutes; XBridge C8 column (4.6 x 75 mm, 3.5 μηη); column temperature 45 °C; flow rate 2.0 mL/minute; detection UV 210 nm, 230 nm, and 254 nm; mobile phase: solvent A = methanesulfonic acid (5%) in 10 mmol sodium octylsulfonate, solvent B = acetonitrile (100%); gradient elusion: 0-1.5 minutes solvent A (95%) and solvent B (5%), 1.5-8.5 minutes solvent A (5%) and solvent B (95%), 8.5- 10.0 minutes solvent A (5%) and solvent B (95%), 10.01 -12.0 minutes solvent A (95%) and solvent B (5%); total run time 12.0 minutes.

Step 3: Preparation of C97-racemic. A solution of C96-racemic (15.0 g, 30.3 mmol) in ethyl acetate (150 mL) under nitrogen was treated with ethanolamine (27.3 mL, 454.1 mmol). The reaction mixture was heated at 90 °C for 3 hours and then cooled to room temperature. The mixture was charged with water (150 mL) and the layers separated. The aqueous layer was extracted with ethyl acetate (75 mL) and the combined organic layers washed with water (2 x 150 mL) followed by saturated aqueous sodium chloride (75 mL). The organic layer was dried over magnesium sulfate, filtered and the filtrate concentrated to a volume of 38 mL. The filtrate was treated with heptane (152 mL) and the solid was collected by filtration. The solid was washed with heptane and dried at 50 °C in a vacuum oven overnight to yield C97-racemic as a solid. Yield: 9.68 g, 26.5 mmol, 88%. LCMS m/z 967.6 (M-1 ). ¹H NMR (400 MHz, DMSO-d₆) δ 7.64 (d, J=9.4 Hz, 1 H), 7.14 (d, J=8.2 Hz, 1 H), 6.56 (s, 1 H), 6.49 (dd, J=8.20, 2.3 Hz, 1 H), 4.78 (dd, J=9.37, 5.1 Hz, 1 H), 4.30 (d, J=14.8 Hz, 1 H), 4.14 (d, J=14.8 Hz, 1 H), 3.77 (s, 3H), 3.75 (s, 3H), 3.45 – 3.53 (m, 1 H), 2.65 – 2.75 (m, 1 H), 2.56 – 2.64 (m, 1 H), 1.38 (s, 9H), 1.30 – 1.35 (m, 2H). HPLC retention time 5.1 minutes; column: Agilent Extended C-18 column (75 mm x 3 mm, 3.5 μΐη); column temperature 45 °C; flow rate 1.0 mL / minute;

detection UV 230 nm; mobile phase: solvent A = acetonitrile (100%), solvent B = acetonitrile (5%) in 10 mM ammonium acetate; gradient elusion: 0-1 .5 minutes solvent B (100%), 1 .5-10.0 minutes solvent B (5%), 10.0-13.0 minutes solvent B (100%); total run time 13.0 minutes. Step 4: Preparation of C97-(2R,3S) enantiomer. A solution of C97-racemic (20.0 g, 54.7 mmol) in ethyl acetate (450 mL) was treated with diatomaceous earth (5.0 g) and filtered through a funnel charged with diatomaceous earth. The filter cake was washed with ethyl acetate (150 mL). The filtrate was charged with diatomaceous earth (20.0 g) and treated with (-)-L-dibenzoyltartaric acid (19.6 g, 54.7 mmol). The slurry was heated at 60 °C for 1.5 hours and then cooled to room temperature. The slurry was filtered and the solid washed with ethyl acetate (90 mL). The solid was collected and dried at 50 °C in a vacuum oven for 17 hours to yield C97-(2R,3S) enantiomer as a solid (mixed with diatomaceous earth). Yield: 17.3 g, 23.9 mmol, 43.6%, 97.6% ee. ¹H NMR (400 MHz, DMSO-de) δ 7.89 – 7.91 (m, 4H), 7.59 – 7.65 (m, 3H), 7.44 – 7.49 (m, 4H), 7.09 (d, J=8.3 Hz, 1 H), 6.53 (d, J=2.3 Hz, 1 H), 6.49 (dd, J=8.3, 2.3 Hz, 1 H), 5.65 (s, 2H), 4.85 (dd, J=9.3, 4.9 Hz, 1 H), 4.30 (d, J=15.3 Hz, 1 H), 4.10 (d, J=15.3 Hz, 1 H), 3.74 (s, 3H), 3.72 (s, 3H), 3.68 – 3.70 (m, 1 H), 2.92 – 2.96 (dd, J=13.6, 5.4 Hz, 1 H), 2.85 – 2.90 (dd, J=13.6, 6.3 Hz, 1 H), 1.36 (s, 9H). HPLC retention time 5.1 minutes; column: Agilent Extended C-18 column (75 mm x 3 mm, 3.5 μηη); column temperature 45 °C; flow rate 1.0 mL / minute; detection UV 230 nm; mobile phase: solvent A = acetonitrile (100%), solvent B = acetonitrile (5%) in 10 mM ammonium acetate; gradient elusion: 0-1 .5 minutes solvent B (100%), 1.5-10.0 minutes solvent B (5%), 10.0-13.0 minutes solvent B (100%); total run time 13.0 minutes. Chiral HPLC retention time 9.1 minutes; column: Chiralcel OD-H column (250 mm x 4.6 mm); column temperature 40 °C; flow rate 1 .0 mL / minute; detection UV 208 nm; mobile phase: solvent A = ethanol (18%), solvent B = heptane (85%); isocratic elusion; total run time 20.0 minutes.

Step 5: Preparation of C98-(2R,3S) enantiomer. A solution of C97-(2R,3S) enantiomer. (16.7 g, 23.1 mmol) in ethyl acetate (301 mL) was treated with diatomaceous earth (18.3 g) and 5% aqueous potassium phosphate tribasic (182 mL). The slurry was stirred for 30 minutes at room temperature, then filtered under vacuum and the filter cake washed with ethyl acetate (2 x 67 mL). The filtrate was washed with 5% aqueous potassium phosphate tribasic (18 mL) and the organic layer dried over magnesium sulfate. The solid was filtered and the filter cake washed with ethyl acetate (33 mL). The filtrate was concentrated to a volume of 42 mL and slowly added to heptane (251 mL) and the resulting solid was collected by filtration. The solid was washed with heptane and dried at 50 °C in a vacuum oven for 19 hours to yield C98- (2R,3S) enantiomer as a solid. Yield: 6.4 g, 17.5 mmol, 76%, 98.8% ee. ¹H NMR (400 MHz, DMSO-de) δ 7.64 (d, J=9.4 Hz, 1 H), 7.14 (d, J=8.2 Hz, 1 H), 6.56 (s, 1 H), 6.49 (dd, J=8.20, 2.3 Hz, 1 H), 4.78 (dd, J=9.37, 5.1 Hz, 1 H), 4.30 (d, J=14.8 Hz, 1 H), 4.14 (d, J=14.8 Hz, 1 H), 3.77 (s, 3H), 3.75 (s, 3H), 3.45 – 3.53 (m, 1 H), 2.65 – 2.75 (m, 1 H), 2.56 – 2.64 (m, 1 H), 1.38 (s, 9H), 1.30 – 1.35 (m, 2H). HPLC retention time 5.2 minutes; column: Agilent Extended C-18 column (75 mm x 3 mm, 3.5 μηη); column temperature 45 °C; flow rate 1.0 mL / minute; detection UV 230 nm; mobile phase: solvent A = acetonitrile (100%), solvent B = acetonitrile (5%) in 10 mM ammonium acetate; gradient elusion: 0-1 .5 minutes solvent B (100%), 1.5-10.0 minutes solvent B (5%), 10.0-13.0 minutes solvent B (100%); total run time 13.0 minutes. Chiral HPLC retention time 8.7 minutes; column: Chiralcel OD-H column (250 mm x 4.6 mm); column temperature 40 °C; flow rate 1.0 mL / minute; detection UV 208 nm; mobile phase: solvent A = ethanol (18%), solvent B = heptane (85%); isocratic elusion; total run time 20.0 minutes.

Step 6: Preparation of C99. A solution of potassium phosphate tribasic N-hydrate (8.71 g, 41 .05 mmol) in water (32.0 mL) at 22 °C was treated with a slurry of C26- mesylate salt (12.1 g, 27.4 mmol, q-NMR potency 98%) in dichloromethane (100.00 mL). The slurry was stirred for 1 hour at 22 °C. The reaction mixture was transferred to a separatory funnel and the layers separated. The aqueous layer was back extracted with dichloromethane (50.0 mL). The organic layers were combined, dried over magnesium sulfate, filtered under vacuum and the filter cake washed with

dichloromethane (2 x 16 mL). The filtrate (-190 mL, amine solution) was used directly in the next step.

A solution of 1 ,1 ‘-carbonyldiimidazole (6.66 g, 41 .0 mmol) in dichloromethane (100 mL) at 22 °C under nitrogen was treated with the previously prepared amine solution (-190 mL) added dropwise using an addition funnel over 3 hour at 22 °C with stirring. After the addition, the mixture was stirred for 1 hour at 22 °C, then treated with C98-(2R,3S) enantiomer. (10.0 g, 27.4 mmol) followed by /V,/V-dimethylformamide (23.00 mL). The reaction mixture was stirred at 22 °C for 3 hours and then heated at 40 °C for 12 hours. The solution was cooled to room temperature and the dichloromethane was removed using the rotary evaporator. The reaction mixture was diluted with ethyl acetate (216.0 mL) and washed with 10% aqueous citric acid (216.0 mL), 5% aqueous sodium chloride (2 x 216.0 mL), dried over magnesium sulfate and filtered under vacuum. The filter cake was washed with ethyl acetate (3 x 13 mL) and the ethyl acetate solution was concentrated on the rotary evaporator to a volume of (-1 10.00 mL) providing a suspension. The suspension (~1 10.00 mL) was warmed to 40 °C and transferred into a stirred solution of heptane (22 °C) over 1 hour, to give a slurry. The slurry was stirred for 1 hour and filtered under vacuum. The filter cake was washed with heptane (3 x 30 mL) and dried under vacuum at 50 °C for 12 hours to afford C99 as a solid. Yield: 18.1 g, 24.9 mmol, 92%. LCMS m/z 728.4 (M+1 ). ¹H NMR (400 MHz, DMSO-d₆) δ 8.09 (s, 1 H), 7.62 (d, J=9.4 Hz, 1 H), 7.33-7.52 (m, 10H), 7.07 (d, J=8.3 Hz, 1 H), 6.51 (d, J=2.3 Hz, 1 H), 6.50 (m, 1 H), 6.44 (dd, J=8.3, 2.3 Hz, 1 H), 6.12 (m, 1 H), 6.07 (s, 1 H), 5.27 (s, 2H), 5.00 (s, 2H), 4.73 (dd, J=9.4, 5.2 Hz, 1 H), 4.38 (d, J=15.0 Hz, 1 H), 4.19 (m, 2H), 3.99 (d, J=15.0 Hz, 1 H), 3.72 (s, 3H), 3.71 (s, 3H), 3.48 (m, 1 H), 3.28 (m, 1 H), 3.12 (m, 1 H), 1 .37 (s, 9H).

Step 7: Preparation of C100. A solution of C99 (46.5 g, 63.9 mmol) in acetonitrile (697 mL and water (372 mL) was treated with potassium persulfate (69.1 g, 255.6 mmol) and potassium phosphate dibasic (50.1 g, 287.5 mmol). The biphasic mixture was heated to 75 °C and vigorously stirred for 1.5 hours. The pH was maintained between 6.0-6.5 by potassium phosphate dibasic addition (-12 g). The mixture was cooled to 20 °C, the suspension was filtered and washed with acetonitrile (50 mL). The filtrate was concentrated using the rotary evaporator and treated with water (50 mL) followed by ethyl acetate (200 mL). The slurry was stirred for 2 hours at room temperature, filtered and the solid dried under vacuum at 40 °C overnight. The solid was slurried in a mixture of ethyl acetate and water (6 : 1 , 390.7 mL) at 20 °C for 1 hour then collected by filtration. The solid was dried in a vacuum oven to yield C100. Yield: 22.1 g, 38.3 mmol, 60%. ¹H NMR (400 MHz, DMSO-d₆) δ 8.17 (br s, 1 H), 7.96 (s, 1 H), 7.58 (d, J=9.6 Hz, 1 H), 7.29-7.50 (m, 10H), 6.49 (dd, J=8.0, 6.0 Hz, 1 H), 6.08 (dd, J=5.6, 5.2 Hz, 1 H), 5.93 (s, 1 H), 5.22 (s, 2H), 4.96 (s, 2H), 4.77 (dd, J=9.6, 5.0 Hz, 1 H), 4.16 (m, 2H), 3.61 (m, 1 H), 3.1 1 (m, 2H), 1.36 (s, 9H). HPLC retention time 6.17 minutes; XBridge C8 column (4.6 x 75 mm, 3.5 μηη); column temperature 45 °C; flow rate 2.0 mL/minute; detection UV 210 nm, 230 nm, and 254 nm; mobile phase: solvent A = methanesulfonic acid (5%) in 10 mmol sodium octylsulfonate, solvent B = acetonitrile (100%); gradient elusion: 0-1 .5 minutes solvent A (95%) and solvent B (5%), 1.5-8.5 minutes solvent A (5%) and solvent B (95%), 8.5-10.0 minutes solvent A (5%) and solvent B (95%), 10.01- 12.0 minutes solvent A (95%) and solvent B (5%); total run time 12.0 minutes.

Step 8: Preparation of C101. A solution of trifluoroacetic acid (120 mL, 1550 mmol) under nitrogen was treated with methoxybenzene (30 mL, 269 mmol) and cooled to -5 °C. Solid C100 (17.9 g, 31.0 mmol) was charged in one portion at -5 °C and the resulting mixture stirred for 3 hours. The reaction mixture was cannulated with nitrogen pressure over 15 minutes to a stirred mixture of Celite (40.98 g) and methyl ferf-butyl ether (550 mL) at 10 °C. The slurry was stirred at 16 °C for 30 minutes, then filtered under vacuum. The filter cake was rinsed with methyl ferf-butyl ether (2 x 100 mL). The solid was collected and slurried in methyl ferf-butyl ether (550 mL) with vigorous stirring for 25 minutes. The slurry was filtered by vacuum filtration and washed with methyl ferf-butyl ether (2 x 250 mL). The solid was collected and dried in a vacuum oven at 60 °C for 18 hours to afford C101 on Celite. Yield: 57.6 g total = C101 + Celite; 16.61 g C101 , 28.1 mmol, 91%. ¹H NMR (400 MHz, DMSO-d₆) δ 8.75-8.95 (br s, 2H), 8.65 (s, 1 H), 8.21 (s, 1 H), 7.30-7.58 (m, 10H), 6.83 (br s, 1 H), 6.65 (br s, 1 H), 6.17 (s, 1 H), 5.30 (s, 2H), 5.03 (s, 2H), 4.45 (br s, 1 H), 4.22 (br s, 2H), 3.77 (m, 1 H), 3.36 (m, 1 H), 3.22 (m, 1 H). ¹⁹F NMR (376 MHz, DMSO-d₆) δ -76.0 (s, 3F). HPLC retention time 5.81 minutes; XBridge C8 column (4.6 x 75 mm, 3.5 μηη); column temperature 45 °C; flow rate 2.0 mL/minute; detection UV 210 nm, 230 nm, and 254 nm; mobile phase: solvent A = methanesulfonic acid (5%) in 10 mmol sodium octylsulfonate, solvent B = acetonitrile (100%); gradient elusion: 0-1.5 minutes solvent A (95%) and solvent B (5%), 1.5-8.5 minutes solvent A (5%) and solvent B (95%), 8.5-10.0 minutes solvent A (5%) and solvent B (95%), 10.01-12.0 minutes solvent A (95%) and solvent B (5%); total run time 12.0 minutes.

Step 9: Preparation of C90. A suspension of C101 (67.0 g, 30% activity on Celite = 33.9 mmol) in acetonitrile (281 .4 mL) was treated with molecular sieves 4AE (40.2 g), C5 (17.9 g, 33.9 mmol), 4-dimethylaminopyridine (10.4 g, 84.9 mmol) and the mixture was stirred at 40°C for 16 hours. The reaction mixture was cooled to 20 °C, filtered under vacuum and the filter cake washed with acetonitrile (2 x 100 mL). The filtrate was concentrated under vacuum to a volume of -50 mL. The solution was diluted with ethyl acetate (268.0 mL) and washed with 10% aqueous citric acid (3 x 134 mL) followed by 5% aqueous sodium chloride (67.0 mL). The organic layer was dried over magnesium sulfate and filtered under vacuum. The filter cake was washed with ethyl acetate (2 x 50 mL) and the filtrate was concentrated to a volume of -60 mL. The filtrate was added slowly to heptane (268 mL) with stirring and the slurry was stirred at 20 °C for 1 hour. The slurry was filtered under vacuum and the filter cake washed with a mixture of heptane and ethyl acetate (4: 1 , 2 x 27 mL). The solid was collected and dried under vacuum for 12 hours at 50 °C to afford a solid. The crude product was purified via chromatography on silica gel (ethyl acetate / 2-propanol), product bearing fractions were combined and the volume was reduced to -60 mL. The solution was added dropwise to heptane (268 mL) with stirring. The slurry was stirred at room temperature for 3 hours, filtered and washed with heptane and ethyl acetate (4: 1 , 2 x 27 mL). The solid was collected and dried under vacuum for 12 hours at 50 °C to afford C90 as a solid. Yield: 16.8 g, 18.9 mmol, 58%. LCMS m/z 889.4 (M+1 ). ¹H NMR (400 MHz, DMSO-cfe) 1 1.90 (br s, 1 H), 9.25 (d, J=8.7 Hz, 1 H), 8.40 (br s, 1 H), 7.98 (s, 1 H), 7.50-7.54 (m, 2H), 7.32- 7.47 (m, 8H), 7.28 (s, 1 H), 6.65 (br s, 1 H), 6.28 (br s, 1 H), 5.97 (s, 1 H), 5.25 (s, 2H), 5.18 (dd, J=8.8, 5 Hz, 1 H), 4.99 (s, 2H), 4.16-4.28 (m, 2H), 3.74-3.80 (m, 1 H), 3.29-3.41 (m, 1 H), 3.13-3.23 (m, 1 H), 1 .42 (s, 9H), 1 .41 (s, 3H), 1.39 (br s, 12H).

Step 10: Preparation of C91. A solution of C90 (14.5 g, 16.3 mmol) in anhydrous N,N- dimethylformamide (145.0 mL) was treated with sulfur trioxide /V,/V-dimethylformamide complex (25.0 g, 163.0 mmol). The reaction mixture was stirred at room temperature for 45 minutes, then transferred to a stirred mixture of 5% aqueous sodium chloride (290 mL) and ethyl acetate (435 mL) at 0 °C. The mixture was warmed to 18 °C and the layers separated. The aqueous layer was extracted with ethyl acetate (145 mL) and the combined organic layers washed with 5% aqueous sodium chloride (3 x 290 mL) followed by saturated aqueous sodium chloride (145 mL). The organic layer was dried over magnesium sulfate, filtered through diatomaceous earth and the filter cake washed with ethyl acetate (72 mL). The filtrate was concentrated to a volume of 36 mL and treated with methyl ferf-butyl ether (290 mL), the resulting slurry was stirred at room temperature for 1 hour. The solid was collected by filtration, washed with methyl ferf- butyl ether (58 mL) and dried at 50 °C for 2 hours followed by 20 °C for 65 hours in a vacuum oven to yield C91 as a solid. Yield: 15.0 g, 15.4 mmol, 95%. LCMS m/z 967.6 (M-1 ). ¹H NMR (400 MHz, DMSO-d₆) δ 1 1.62 (br s, 1 H), 9.29 (d, J=8.8 Hz, 1 H), 9.02 (s, 1 H), 7.58-7.61 (m, 2H), 7.38-7.53 (m, 9H), 7.27 (s, 1 H), 7.07 (s, 1 H), 6.40 (br d, J=8.0 Hz, 1 H), 5.55 (s, 2H), 5.25 (s, 2H), 5.20 (dd, J=8.8, 5.6 Hz, 1 H), 4.46 (br dd, half of ABX pattern, J=17.0, 5.0 Hz, 1 H), 4.38 (br dd, half of ABX pattern, J=17.0, 6.0 Hz, 1 H), 3.92- 3.98 (m, 1 H), 3.79-3.87 (m, 1 H), 3.07-3.17 (m, 1 H), 1.40 (s, 9H), 1.39 (s, 3H), 1.38 (s, 12H).

Step 11 : Preparation of C92. A solution of C91 (20.0 g, 20.6 mmol) in

dichloromethane (400 mL) was concentrated under reduced pressure (420 mmHg) at 45 °C to a volume of 200 mL. The solution was cooled to -5 °C and treated with 1 M boron trichloride in dichloromethane (206.0 mL, 206.0 mmol) added dropwise over 40 minutes. The reaction mixture was warmed to 15 °C over 1 hour with stirring. The slurry was cooled to -15 °C and treated with a mixture of 2,2,2-trifluoroethanol (69.2 mL) and methyl ferf-butyl ether (400 mL), maintaining the temperature at -15 °C. The reaction mixture was warmed to 0 °C over 1 hour. The suspension was filtered using nitrogen pressure and the solid washed with methyl ferf-butyl ether (2 x 200 mL).

Nitrogen was passed over the solid for 2 hours. The solid was collected and suspended in methyl ferf-butyl ether (400 mL) for 1 hour with stirring at 18 °C. The suspension was filtered using nitrogen pressure and the solid washed with methyl ferf-butyl ether (2 x 200 mL). Nitrogen was passed over the resulting solid for 12 hours. A portion of the crude product was neutralized with 1 M aqueous ammonium formate to pH 5.5 with minimal addition of /V,/V-dimethylformamide to prevent foaming. The feed solution was filtered and purified via reverse phase chromatography (C-18 column; acetonitrile / water gradient with 0.2% formic acid modifier). The product bearing fractions were combined and concentrated to remove acetonitrile. The solution was captured on a GC-161 M column, washed with deionized water and blown dry with nitrogen pressure. The product was released using a mixture of methanol / water (10: 1 ) and the product bearing fractions were added to a solution of ethyl acetate (6 volumes). The solid was collected by filtration to afford C92 as a solid. Yield: 5.87 g, 9.28 mmol. LCMS m/z 633.3 (M+1 ). ¹H NMR (400 MHz, DMSO-d₆) δ 9.22 (d, J=8.7 Hz, 1 H), 8.15 (s, 1 H), 7.26-7.42 (br s, 2H), 7.18-7.25 (m, 1 H), 6.99 (s, 1 H), 6.74 (s, 1 H), 6.32-6.37 (m, 1 H), 5.18 (dd, J=8.7, 5.7 Hz, 1 H), 4.33 (br d, J=4.6 Hz, 2H), 3.94-4.00 (m, 1 H), 3.60-3.68 (m, 1 H), 3.19-3.27 (m, 1 H), 1.40 (s, 3H), 1.39 (s, 3H).

PAPER

Journal of Medicinal Chemistry (2014), 57(9), 3845-3855

Siderophore Receptor-Mediated Uptake of Lactivicin Analogues in Gram-Negative Bacteria

^†Medicinal Chemistry, ^⧧Computational Chemistry, ^§Antibacterials Research Unit, and ^¶Structural Biology, Pfizer Global Research and Development, Eastern Point Road, Groton, Connecticut 06340, United States

J. Med. Chem., 2014, 57 (9), pp 3845–3855

DOI: 10.1021/jm500219c

Publication Date (Web): April 2, 2014

*Phone: (860)-686-1788. E-mail: seungil.han@pfizer.com.

Cite this:J. Med. Chem. 57, 9, 3845-3855

Abstract

Multidrug-resistant Gram-negative pathogens are an emerging threat to human health, and addressing this challenge will require development of new antibacterial agents. This can be achieved through an improved molecular understanding of drug–target interactions combined with enhanced delivery of these agents to the site of action. Herein we describe the first application of siderophore receptor-mediated drug uptake of lactivicin analogues as a strategy that enables the development of novel antibacterial agents against clinically relevant Gram-negative bacteria. We report the first crystal structures of several sideromimic conjugated compounds bound to penicillin binding proteins PBP3 and PBP1a from Pseudomonas aeruginosa and characterize the reactivity of lactivicin and β-lactam core structures. Results from drug sensitivity studies with β-lactamase enzymes are presented, as well as a structure-based hypothesis to reduce susceptibility to this enzyme class. Finally, mechanistic studies demonstrating that sideromimic modification alters the drug uptake process are discussed.

PAPER

Pyridone-Conjugated Monobactam Antibiotics with Gram-Negative Activity

^†Worldwide Medicinal Chemistry, ^‡Computational Chemistry, ^§Antibacterials Research Unit, ^∥Pharmacokinetics, Dynamics & Metabolism, ^⊥Structural Biology, Pfizer Global Research and Development, Eastern Point Road, Groton, Connecticut 06340, United States

J. Med. Chem., 2013, 56 (13), pp 5541–5552

DOI: 10.1021/jm400560z

Publication Date (Web): June 11, 2013

*Phone: 860-441-3522. E-mail: matthew.f.brown@pfizer.com.

Herein we describe the structure-aided design and synthesis of a series of pyridone-conjugated monobactam analogues with in vitro antibacterial activity against clinically relevant Gram-negative species including Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli. Rat pharmacokinetic studies with compound 17 demonstrate low clearance and low plasma protein binding. In addition, evidence is provided for a number of analogues suggesting that the siderophore receptors PiuA and PirA play a role in drug uptake in P. aeruginosa strain PAO1.

17 as a solid. Yield: 5.87 g, 9.28 mmol. LCMS m/z 633.3 (M+1). 1H NMR (400 MHz, DMSOd6) δ 9.22 (d, J=8.7 Hz, 1H), 8.15 (s, 1H), 7.26-7.42 (br s, 2H), 7.18-7.25 (m, 1H), 6.99 (s, 1H), 6.74 (s, 1H), 6.32-6.37 (m, 1H), 5.18 (dd, J=8.7, 5.7 Hz, 1H), 4.33 (br d, J=4.6 Hz, 2H), 3.94-4.00 (m, 1H), 3.60-3.68 (m, 1H), 3.19-3.27 (m, 1H), 1.40 (s, 3H), 1.39 (s, 3H).

Nc1nc(cs1)\C(=N\OC(C)(C)C(=O)O)C(=O)N[C@@H]3C(=O)N([C@@H]3CNC(=O)NCC2=CC(=O)C(O)=CN2O)S(=O)(=O)O

PAPER

Process Development for the Synthesis of Monocyclic β-Lactam Core 17

Manjinder S. Lall^*

, Yong Tao^*, Joel T. Arcari, David C. Boyles, Matthew F. Brown, David B. Damon, Susan C. Lilley, Mark J. Mitton-Fry, Jeremy Starr

, Andrew Morgan Stewart III, and Jianmin Sun

Pfizer Worldwide Research and Development, Eastern Point Road, Groton, Connecticut 06340, United States

Org. Process Res. Dev., Article ASAP

DOI: 10.1021/acs.oprd.7b00359

Publication Date (Web): January 4, 2018

*E-mail: manjinder.lall@pfizer.com., *E-mail: yong.tao@pfizer.com.

Process development and multikilogram synthesis of the monocyclic β-lactam core 17 for a novel pyridone-conjugated monobactam antibiotic is described. Starting with commercially available 2-(2,2-diethoxyethyl)isoindoline-1,3-dione, the five-step synthesis features several telescoped operations and direct isolations to provide significant improvement in throughput and reduced solvent usage over initial scale-up campaigns. A particular highlight in this effort includes the development of an efficient Staudinger ketene–imine [2 + 2] cycloaddition reaction of N-Boc-glycine ketene 12 and imine 9 to form racemic β-lactam 13 in good isolated yield (66%) and purity (97%). Another key feature in the synthesis involves a classical resolution of racemic amine 15 to afford single enantiomer salt 17 in excellent isolated yield (45%) with high enantiomeric excess (98%).

https://pubs.acs.org/doi/suppl/10.1021/acs.oprd.7b00359/suppl_file/op7b00359_si_001.pdf

Nc1nc(cs1)\C(=N\OC(C)(C)C(=O)O)C(=O)N[C@@H]3C(=O)N([C@@H]3CNC(=O)NCC2=CC(=O)C(O)=CN2O)S(=O)(=O)O

////////////////////////////////////////////////////////////////////////

J. Med. Chem., 2013, 56 (13), pp 5541–5552

DOI: 10.1021/jm400560z

OXYGEN ANALOGUE…………..

1380110-45-1, C₂₀ H₂₃ N₇ O₁₃ S_2, 633.57

Propanoic acid, 2-[[(Z)-[1-(2-amino-4-thiazolyl)-2-[[(2R,3S)-2-[[[[(1,4-dihydro-1,5-dihydroxy-4-oxo-2-pyridinyl)methoxy]carbonyl]amino]methyl]-4-oxo-1-sulfo-3-azetidinyl]amino]-2-oxoethylidene]amino]oxy]-2-methyl-

2-[[(Z)-[1-(2-Amino-4-thiazolyl)-2-[[(2R,3S)-2-[[[[(1,4-dihydro-1,5-dihydroxy-4-oxo-2-pyridinyl)methoxy]carbonyl]amino]methyl]-4-oxo-1-sulfo-3-azetidinyl]amino]-2-oxoethylidene]amino]oxy]-2-methylpropanoic acid

18 as a light yellow solid. Yield: 43 mg, 0.068 mmol, 51%. LCMS m/z 634.4 (M+1). 1H NMR (400 MHz, DMSO-d6), characteristic peaks: δ 9.29 (d, J=8.5 Hz, 1H), 8.10 (s, 1H), 7.04-7.10 (m, 1H), 7.00 (s, 1H), 6.75 (s, 1H), 5.05-5.30 (m, 3H), 4.00-4.07 (m, 1H), 1.42 (s, 3H), 1.41 (s, 3H).

Nc1nc(cs1)\C(=N\OC(C)(C)C(=O)O)C(=O)N[C@@H]3C(=O)N([C@@H]3CNC(=O)OCC2=CC(=O)C(O)=CN2O)S(=O)(=O)O

Step 4: Preparation of 18-Bis Na salt. A suspension of 5 (212 mg, 0.33 mmol) in water (10 mL) was cooled to 0 oC and treated with a solution of sodium bicarbonate (56.4 mg, 0.67 mmol) in water (2 mL), added dropwise. The reaction mixture was cooled to -70 oC (frozen) and lyophilized to afford 18-Bis Na salt as a white solid. Yield: 210 mg, 0.31 mmol, 93%. LCMS m/z 632.5 (M-1). 1H NMR (400 MHz, D2O) δ 7.87 (s, 1H), 6.94 (s, 1H), 6.92 (s, 1H), 5.35 (d, J=5 Hz, 1H), 5.16 (s, 2H), 4.46-4.52 (m, 1H), 3.71 (dd, half of ABX pattern, J=14.5, 6 Hz, 1H), 3.55 (dd, half of ABX pattern, J=14.5, 6 Hz, 1H), 1.43 (s, 3H), 1.42 (s, 3H).

WO 2012073138

Inventors	Matthew Frank Brown, Seungil Han, Manjinder Lall, Mark. J. Mitton-Fry, Mark Stephen Plummer, Hud Lawrence Risley, Veerabahu Shanmugasundaram, Jeremy T. Starr,
Applicant	Pfizer Inc.

Example 5

disodium 2-({[(1Z)-1 -(2-amino-1 ,3-thiazol-4-yl)-2-({(2R,3S)-2-[({[(1 ,5-dihydroxy-4- oxo-1 ,4-dihydropyridin-2-yl)methoxy]carbonyl}amino)methyl]-4-oxo-1 – sulfonatoazetidin-3-yl}amino)-2-oxoethylidene]amino}oxy)-2-methylpropanoate

(C104-Bis Na salt).

Step 1 : Preparation of C102. A solution of C28 (300 mg, 0.755 mmol) in

tetrahydrofuran (10 mL) was treated with 1 , 1 ‘-carbonyldiimidazole (379 mg, 2.26 mmol) at room temperature and stirred for 20 hours. The yellow reaction mixture was treated with a solution of C9 (286 mg, 0.543 mmol) in tetrahydrofuran (25 mL). The mixture was stirred for 6 hours at room temperature, then treated with water (20 mL) and extracted with ethyl acetate (3 x 25 mL). The combined organic layers were dried over sodium sulfate, filtered and concentrated in vacuo. The crude material was purified via chromatography on silica gel (heptane / ethyl acetate / 2-propanol) to afford C102 as a light yellow solid. Yield: 362 mg, 0.381 mmol, 62%. LCMS m/z 950.4 (M+1 ). ¹H NMR (400 MHz, DMSO-de), characteristic peaks: δ 9.31 (d, J=8.4 Hz, 1 H), 8.38 (s, 1 H), 8.00 (s, 1 H), 7.41 (br d, J=8.2 Hz, 2H), 7.36 (br d, J=8.8 Hz, 2H), 7.26 (s, 1 H), 6.10 (s, 1 H), 5.20 (s, 2H), 4.92 (br s, 4H), 3.77 (s, 3H), 3.76 (s, 3H), 1.45 (s, 9H), 1.38 (s, 9H). Step 2: Preparation of C103. A solution of C102 (181 mg, 0.191 mmol) in anhydrous /V,/V-dimethylformamide (2.0 mL) was treated with sulfur trioxide pyridine complex (302 mg, 1.91 mmol). The reaction mixture was allowed to stir at room temperature for 6 hours, then cooled to 0 °C and quenched with water. The resulting solid was collected by filtration and dried in vacuo to yield C103 as a white solid. Yield: 145 mg, 0.14 mmol, 74%. APCI m/z 1028.5 (M-1 ). ¹H NMR (400 MHz, DMSO-d₆), characteristic peaks: δ 1 1.65 (br s, 1 H), 9.37 (d, J=8.6 Hz, 1 H), 8.87 (s, 1 H), 7.49 (br d, J=8.6 Hz, 2H), 7.43 (br d, J=8.6 Hz, 2H), 7.26 (s, 1 H), 7.01 (br d, J=8.9 Hz, 2H), 7.00 (br d, J=8.8 Hz, 2H), 5.43 (s, 2H), 5.20 (dd, J=8.4, 6 Hz, 1 H), 4.01-4.07 (m, 1 H), 3.78 (s, 3H), 3.77 (s, 3H), 3.50- 3.58 (m, 1 H), 3.29-3.37 (m, 1 H), 1.44 (s, 9H), 1.37 (s, 9H). Step 3: Preparation of C104. A solution of C103 (136 mg, 0.132 mmol) in anhydrous dichloromethane (5 mL) was treated with 1 M boron trichloride in p-xylenes (0.92 mL, 0.92 mmol) and allowed to stir at room temperature for 40 minutes. The reaction mixture was cooled in an ice bath, quenched with water (0.4 mL), and transferred into a solution of methyl ferf-butyl ether: heptane (1 :2, 12 mL). The solvent was removed in vacuo and the crude product was purified via reverse phase chromatography (C-18 column; acetonitrile / water gradient with 0.1 % formic acid modifier) to yield C104 as a light yellow solid. Yield: 43 mg, 0.068 mmol, 51 %. LCMS m/z 634.4 (M+1 ). ¹H NMR (400 MHz, DMSO-de), characteristic peaks: δ 9.29 (d, J=8.5 Hz, 1 H), 8.10 (s, 1 H), 7.04- 7.10 (m, 1 H), 7.00 (s, 1 H), 6.75 (s, 1 H), 5.05-5.30 (m, 3H), 4.00-4.07 (m, 1 H), 1 .42 (s, 3H), 1 .41 (s, 3H).

Step 4: Preparation of C104-Bis Na salt. A suspension of C104 (212 mg, 0.33 mmol) in water (10 mL) was cooled to 0 °C and treated with a solution of sodium bicarbonate (56.4 mg, 0.67 mmol) in water (2 mL), added dropwise. The reaction mixture was cooled to -70 °C (frozen) and lyophilized to afford C104-Bis Na salt as a white solid. Yield: 210 mg, 0.31 mmol, 93%. LCMS m/z 632.5 (M-1 ). ¹H NMR (400 MHz, D₂0) δ 7.87 (s, 1 H), 6.94 (s, 1 H), 6.92 (s, 1 H), 5.35 (d, J=5 Hz, 1 H), 5.16 (s, 2H), 4.46-4.52 (m, 1 H), 3.71 (dd, half of ABX pattern, J=14.5, 6 Hz, 1 H), 3.55 (dd, half of ABX pattern, J=14.5, 6 Hz, 1 H), 1.43 (s, 3H), 1 .42 (s, 3H).

////////////Pfizer, monobactam, PF-?, preclinical, pf, pfizer

p-Aminophenol

Uncategorized Comments Off

Feb 232018

p-Aminophenol [123-30-8].

M.p. 182 °C; 1H NMR (300 MHz, d6-DMSO): 4.37 (br s, 2H, NH2), 6.37-6.44 (m, 2HAr), 6.44-6.50 (m, 2HAr), 8.33 (br s, 1H, OH);

13C NMR (75 MHz, d6-DMSO): δ 115.2 (2 CHAr), 115.5 (2 CHAr), 140.7 (Cq Ar), 148.2 (Cq Ar);

IR (ATR) max: 3338, 3279, 1471; MS (ESI+ ): 110.1 ([M+H]+ , 100).

1D 1H, 7.4 spectrum for 4-Aminophenol

1D 1H ABOVE

2D [1H,1H]-TOCSY, 7.4 spectrum for 4-Aminophenol

2D [1H,1H]-TOCSY ABOVE

1D 13C, 7.4 spectrum for 4-Aminophenol

1D 13C ABOVE

1D DEPT90, 7.4 spectrum for 4-Aminophenol

1D DEPT90 ABOVE

1D DEPT135, 7.4 spectrum for 4-Aminophenol

1D DEPT135 ABOVE

2D [1H,13C]-HSQC, 7.4 spectrum for 4-Aminophenol

2D [1H,13C]-HSQC ABOVE

2D [1H,13C]-HMBC, 7.4 spectrum for 4-Aminophenol

2D [1H,13C]-HMBC ABOVE

NKTR 214

phase 2, Uncategorized Comments Off

Feb 232018

Image result for NKTR 214

CAS 946414-94-4

BMS 936558
MDX 1106
NKTR 214
ONO 4538
Opdivio
NIVOLUMAB

Pegylated engineered interleukin-2 (IL-2) with altered receptor binding

NKTR-214 is a cytokine (investigational agent) that is designed to target CD122, a protein which is found on certain immune cells (known as CD8+ T Cells and Natural Killer Cells) to expand these cells to promote their anti-tumor effects. Nivolumab is a full human monoclonal antibody that binds to a molecule called PD-1 (programmed cell death protein 1) on immune cells and promotes anti-tumor effects.

Protein Sequence

Sequence Length: 1308, 440, 440, 214, 214multichain; modified (modifications unspecified)

NKTR-214 is a CD122-biased cytokine in phase II clinical trials at the M.D. Anderson Cancer Center for the treatment of advanced sarcoma in combination with nivolumab.

Image result for NKTR 214

M.D. Anderson Cancer Center, PHASE 2, SARCOMA

NKTR-214 in combination with OPDIVO^® (nivolumab)

RESEARCH FOCUS: Immuno-oncology

DISCOVERED AND WHOLLY OWNED BY NEKTAR

In clinical collaboration with

About NKTR-214, Nektar’s Lead Immuno-oncology Candidate

NKTR-214 is a CD122-biased agonist designed to stimulate the patient’s own immune system to fight cancer. NKTR-214 is designed to grow specific cancer-killing T cells and natural killer (NK) cell populations in the body which fight cancer, which are known as endogenous tumor-infiltrating lymphocytes (TILs). NKTR-214 stimulates these cancer-killing immune cells in the body by targeting CD122 specific receptors found on the surface of these immune cells, known as CD8+ effector T cells and Natural Killer (NK) cells. CD122, which is also known as the Interleukin-2 receptor beta subunit, is a key signaling receptor that is known to increase proliferation of these effector T cells.¹ In preclinical studies, treatment with NKTR-214 results in a rapid expansion of these cells and mobilization into the tumor micro-environment. NKTR-214 has an antibody-like dosing regimen similar to the existing checkpoint inhibitor class of approved medicines.

In preclinical studies, NKTR-214 demonstrated a mean ratio of 450:1 within the tumor micro-environment of CD8-positive effector T cells, which promote tumor destruction, compared with CD4-positive regulatory T cells, which are a type of cell that can suppress tumor-killing T cells.²Furthermore, a single dose of NKTR-214 resulted in a 500-fold AUC exposure within the tumor compared with an equivalent dose of the existing IL-2 therapy, enabling, for the first time, an antibody-like dosing regimen for a cytokine.² In dosing studies in non-human primates, there was no evidence of severe side effects such as low blood pressure or vascular leak syndrome with NKTR-214 at predicted clinical therapeutic doses.² NKTR-214 has a range of potential uses against multiple tumor types, including melanoma (the most serious type of skin cancer), kidney cancer and non-small cell lung cancer (the most common form of lung cancer).

A Phase 1 study evaluating NKTR-214 as a single agent in patients with locally recurrent or metastatic solid tumors including melanoma, renal cell carcinoma (RCC), bladder, colorectal and other solid tumors is ongoing with patient enrollment complete. Results from this Phase 1 trial were presented at the Society for Immunotherapy of Cancer (SITC) 2016 Annual Meeting and showed encouraging evidence of anti-tumor activity, and a favorable safety and tolerability profile. (Poster #387)

In September 2016, Nektar entered into a clinical collaboration with Bristol-Myers Squibb to evaluate NKTR-214 as a potential combination treatment regimen with Opdivo (nivolumab) in five tumor types and eight potential indications. The Phase 1/2 PIVOT clinical trials, known as PIVOT-02 and PIVOT-04 will enroll up to 260 patients and will evaluate the potential for the combination of Opdivo (nivolumab) and NKTR-214 to show improved and sustained efficacy and tolerability above the current standard of care in melanoma, kidney, triple-negative breast cancer, bladder and non-small cell lung cancer patients.

In May 2017, Nektar entered into a research collaboration with Takeda to explore the combination of NKTR-214 with five oncology compounds from Takeda’s cancer portfolio including a SYK-inhibitor and a proteasome inhibitor. The collaboration will explore the anti-cancer activity of NKTR-214 combined with five different targeted mechanisms in preclinical tumor models of lymphoma, melanoma and colorectal cancer to identify which combination treatment regimens show the most promise for possible advancement into the clinic.

Under the terms of the collaboration, the companies will share costs related to the preclinical studies and each will contribute their respective compounds to the research collaboration. Nektar and Takeda will each maintain global commercial rights to their respective drugs and/or drug candidates.

Additional development plans for NKTR-214 include combination studies with additional checkpoint inhibitors, cell therapies and vaccines.

About the Excel NKTR-214 Phase 1/2 Study

The dose-escalation stage of the Excel Phase 1/2 study is designed to evaluate safety, efficacy, and define the recommended Phase 2 dose of NKTR-214 in approximately 20 patients with solid tumors. In addition to a determination of the recommended Phase 2 dose, the study will assess preliminary anti-tumor activity, including objective response rate (ORR). The immunologic effect of NKTR-214 on tumor-infiltrating lymphocytes (TILs) and other immune infiltrating cells in both blood and tumor tissue will also be assessed. Enrollment in the dose escalation study is completed. More information on the Excel Phase 1/2 study can be found on clinicaltrials.gov.

About the PIVOT Phase 1/2 Program: NKTR-214 in combination with OPDIVO^® (nivolumab)

The dose escalation stage of the PIVOT program (PIVOT-02 Phase 1/2 study) is underway and will determine the recommended Phase 2 dose of NKTR-214 administered in combination with nivolumab. The study is first evaluating the clinical benefit, safety, and tolerability of combining NKTR-214 with nivolumab in approximately 30 patients with melanoma, renal cell carcinoma or non-small cell lung cancer. Once the recommended Phase 2 dose is achieved, the study will expand into additional patients for each tumor type. The second phase of the expansion cohorts in the PIVOT program (PIVOT-04 Phase 2 study) will evaluate safety and efficacy of the combination in up to 260 patients, in five tumor types and eight indications, including first and second-line melanoma, second-line renal cell carcinoma in immune-oncology therapy (IO) naïve and IO-relapsed patients, second-line non-small cell lung cancer in IO-naïve and IO-relapsed patients, first-line urothelial carcinoma, and second-line triple negative breast cancer. This study is expected to initiate in the second quarter of 2017.

Information on the PIVOT-02 study can be found on clinicaltrials.gov.

About the PROPEL Phase 1/2 Program: NKTR-214 in combination with TECENTRIQ^® (atezolizumab) or KEYTRUDA^®(pembrolizumab)

The dose escalation stage of the PROPEL program will determine the recommended Phase 2 dose of NKTR-214 administered in combination with anti-PD-L1 agent, atezolizumab or anti-PD-1 agent, pembrolizumab. The study will evaluate the clinical benefit, safety and tolerability of combining NKTR-214 with atezolizumab or pembrolizumab and will enroll patients into two separate arms concurrently. The first arm will evaluate an every three-week dose regimen of NKTR-214 in combination with atezolizumab in up to 30 patients in approved treatment settings of atezolizumab, including patients with non-small cell lung cancer or bladder cancer. The second arm will evaluate an every three-week dose regimen of NKTR-214 in combination with pembrolizumab in up to 30 patients in approved treatment settings of pembrolizumab, including patients with melanoma, non-small cell lung cancer or bladder cancer.

Information on the PROPEL study can be found on clinicaltrials.gov.

References

1Boyman, J., et al., Nature Reviews Immunology, 2012, 12, 180-190.

2Charych, D., et al., Clin Can Res; 22(3) February 1, 2016

http://www.nektar.com/application/files/7714/7887/7212/2016_SITC_NKTR-214-clinical_poster.pdf

https://www.google.co.in/patents/WO2015125159A1?cl=en

Inventors	Murali Krishna Addepalli, Deborah H. Charych, Seema Kantak, Steven Robert Lee
Applicant	Nektar Therapeutics (India) Pvt. Ltd., Nektar Therapeutics

////////////946414-94-4, BMS 936558, MDX 1106, NKTR 214, ONO 4538, Opdivio, NIVOLUMAB, PHASE 2

Entecavir, энтекавир , إينتيكافير , 恩替卡韦 , エンテカビル

GENERIC, Uncategorized Comments Off

Feb 232018

Entecavir

Molecular FormulaC₁₂H₁₅N₅O₃
Average mass277.279 Da

NNU2O4609D

QA-0464

SQ 34,676

SQ34676

Teviral

UNII:NNU2O4609D

Entecavir; 142217-69-4; Baraclude; BMS 200475; Anhydrous entecavir; UNII-NNU2O4609D

энтекавир [Russian] [INN]

إينتيكافير [Arabic] [INN]

恩替卡韦 [Chinese] [INN]

エンテカビル JAPANESE

2-amino-9-[(1S,3R,4S)-4-hydroxy-3-(hydroxymethyl)-2-methylidenecyclopentyl]-9H-purin-6-ol

6H-Purin-6-one, 2-amino-1,9-dihydro-9-((1S,3R,4S)-4-hydroxy-3-(hydroxymethyl)-2-methylenecyclopentyl)-

6H-Purin-6-one, 2-amino-1,9-dihydro-9-[(1S,3R,4S)-4-hydroxy-3-(hydroxymethyl)-2-methylenecyclopentyl]-

9H-purin-6-ol, 2-amino-9-[(1S,3R,4S)-4-hydroxy-3-(hydroxymethyl)-2-methylenecyclopentyl]-

Baraclude[Trade name]

CAS 142217-69-4

Entecavir monohydrate 209216-23-9

Baraclude (Entecavir) Film Coated Tablets & Oral Solution
Company: Bristol-Myers Squibb Pharmaceutical Co.
Application No.: 021797 & 021798
Approval Date: 03/29/2005

Chemistry Review(s) (PDF)

BARACLUDE® is the tradename for entecavir, a guanosine nucleoside analogue with selective activity against HBV. The chemical name for entecavir is 2-amino-1,9-dihydro-9-[(1S,3R,4S)-4-hydroxy-3-(hydroxymethyl)-2-methylenecyclopentyl]-6H-purin-6-one, monohydrate. Its molecular formula is C₁₂H₁₅N₅O₃•H₂O, which corresponds to a molecular weight of 295.3. Entecavir has the following structural formula:

BARACLUDE® (entecavir) Structural Formula Illustration

Entecavir is a white to off-white powder. It is slightly soluble in water (2.4 mg/mL), and the pH of the saturated solution in water is 7.9 at 25° C ± 0.5° C.

BARACLUDE film-coated tablets are available for oral administration in strengths of 0.5 mg and 1 mg of entecavir. BARACLUDE 0.5 mg and 1 mg film-coated tablets contain the following inactive ingredients: lactose monohydrate, microcrystalline cellulose, crospovidone, povidone, and magnesium stearate. The tablet coating contains titanium dioxide, hypromellose, polyethylene glycol 400, polysorbate 80 (0.5 mg tablet only), and iron oxide red (1 mg tablet only). BARACLUDE Oral Solution is available for oral administration as a ready-to-use solution containing 0.05 mg of entecavir per milliliter. BARACLUDE Oral Solution contains the following inactive ingredients: maltitol, sodium citrate, citric acid, methylparaben, propylparaben, and orange flavor.

Title: Entecavir

CAS Registry Number: 142217-69-4

CAS Name: 2-Amino-1,9-dihydro-9-[(1S,3R,4S)-4-hydroxy-3-(hydroxymethyl)-2-methylenecyclopentyl]-6H-purin-6-one

Molecular Formula: C12H15N5O3

Molecular Weight: 277.28

Percent Composition: C 51.98%, H 5.45%, N 25.26%, O 17.31%

Literature References: Deoxyguanine nucleoside analog; inhibits hepatitis B virus (HBV) DNA polymerase. Prepn: R. Zahler, W. A. Slusarchyk, EP481754; eidem,US5206244 (1992, 1993 both to Squibb); G. S. Bisacchi et al.,Bioorg. Med. Chem. Lett.7, 127 (1997). In vitro antiviral activity: S. F. Innaimo et al,Antimicrob. Agents Chemother.41, 1444 (1997). Review of pharmacology and clinical experience: P. Honkoop, R. A. de Man, Expert Opin. Invest. Drugs12, 683-688 (2003); T. Shaw, S. Locarnini, Expert Rev. Anti Infect. Ther.2, 853-871 (2004). Clinical comparisons with lamivudine in chronic hepatitis B: T.-T. Chang et al., N. Engl. J. Med.354, 1001 (2006); C.-L. Lai et al., ibid. 1011.

Derivative Type: Monohydrate

CAS Registry Number: 209216-23-9

Manufacturers’ Codes: BMS-200475; SQ-200475

Trademarks: Baraclude (BMS)

Molecular Formula: C12H15N5O3.H2O

Molecular Weight: 295.29

Percent Composition: C 48.81%, H 5.80%, N 23.72%, O 21.67%

Properties: White to off-white powder, mp >220°. [a]D +35.0° (c = 0.38 in water). Soly in water: 2.4 mg/ml. pH of saturated soln in water is 7.9 at 25°±0.5°.

Melting point: mp >220°

Optical Rotation: [a]D +35.0° (c = 0.38 in water)

Therap-Cat: Antiviral.

Keywords: Antiviral; Purines/Pyrimidinones.

Antiviral agents used against HBV

Entecavir is an oral antiviral drug used in the treatment of hepatitis B infection. It is marketed under the trade name Baraclude (BMS).

Entecavir is a guanine analogue that inhibits all three steps in the viral replication process, and the manufacturer claims that it is more efficacious than previous agents used to treat hepatitis B (lamivudine and adefovir). It was approved by the U.S. Food and Drug Administration (FDA) in March 2005.

For the treatment of chronic hepatitis B virus infection in adults with evidence of active viral replication and either evidence of persistent elevations in serum aminotransferases (ALT or AST) or histologically active disease.

Entecavir (ETV), sold under the brand name Baraclude, is an antiviral medication used in the treatment of hepatitis B virus (HBV) infection.^[1] In those with both HIV/AIDS and HBV antiretroviral medication should also be used.^[1] Entecavir is taken by mouth as a tablet or solution.^[1]

Common side effects include headache, nausea, high blood sugar, and decreased kidney function.^[1] Severe side effects include enlargement of the liver, high blood lactate levels, and liver inflammation if the medication is stopped.^[1] While there appears to be no harm from use during pregnancy, this use has not been well studied.^[4] Entecavir is in the nucleoside reverse transcriptase inhibitors(NRTIs) family of medications.^[1] It prevents the hepatitis B virus from multiplying by blocking reverse transcriptase.^[1]

Entecavir was approved for medical use in 2005.^[1] It is on the World Health Organization’s List of Essential Medicines, the most effective and safe medicines needed in a health system.^[5] In the United States as of 2015 it is not available as a generic medication.^[6]The wholesale price is about 392 USD for a typical month supply as of 2016 in the United States.^[7]

Medical uses

Entecavir is mainly used to treat chronic hepatitis B infection in adults and children 2 years and older with active viral replication and evidence of active disease with elevations in liver enzymes.^[2] It is also used to prevent HBV reinfection after liver transplant^[8] and to treat HIV patients infected with HBV. Entecavir is weakly active against HIV, but is not recommended for use in HIV-HBV co-infected patients without a fully suppressive anti-HIV regimen^[9] as it may select for resistance to lamivudine and emtricitabine in HIV.^[10]

The efficacy of entecavir has been studied in several randomized, double-blind, multicentre trials. Entecavir by mouth is effective and generally well tolerated treatment.^[11]

Pregnancy and breastfeeding

It is considered pregnancy category C in the United States, and currently no adequate and well-controlled studies exist in pregnant women.^[12]

Side effects

The majority of people who use entecavir have little to no side effects.^[13] The most common side effects include headache, fatigue, dizziness, and nausea.^[2] Less common effects include trouble sleeping and gastrointestinal symptoms such as sour stomach, diarrhea, and vomiting.^[14]

Serious side effects from entecavir include lactic acidosis, liver problems, liver enlargement, and fat in the liver.^[15]

Laboratory tests may show an increase in alanine transaminase (ALT), hematuria, glycosuria, and an increase in lipase.^[16] Periodic monitoring of hepatic function and hematology are recommended.^[2]

Mechanism of action

Entecavir is a nucleoside analog,^[17] or more specifically, a deoxyguanosine analogue that belongs to a class of carbocyclic nucleosidesand inhibits reverse transcription, DNA replication and transcription in the viral replication process. Other nucleoside and nucleotide analogues include lamivudine, telbivudine, adefovir dipivoxil, and tenofovir.

Entecavir reduces the amount of HBV in the blood by reducing its ability to multiply and infect new cells.^[18]

Administration

Entecavir is take by mouth as a tablet or solution. Doses are based on a person’s weight.^[15] The solution is recommended for children more than 2 years old who weigh up to 30 kg. Entecavir is recommended on an empty stomach at least 2 hours before or after a meal, generally at the same time every day. It is not used in children less than 2 years old. Dose adjustments are also recommended for people with decreased kidney function.^[15]

History

1992: SQ-34676 at Squibb as part of anti-herpes virus program^[19]
1997: BMS 200475 developed at BMS pharmaceutical research institute as antiviral nucleoside analogue à Activity demonstrated against HBV, HSV-1, HCMV, VZV in cell lines & no or little activity against HIV or influenza^[20]
Superior activity observed against HBV pushed research towards BMS 200475, its base analogues and its enantiomer against HBV in HepG2.2.15 cell line^[20]
Comparison to other NAs, proven more selective potent inhibitor of HBV by virtue of being Guanine NA^[21]
1998: Inhibition of hepadnaviral polymerases was demonstrated in vitro in comparison to a number of NAs-TP^[22]
Metabolic studies showed more efficient phosphorylation to triphosphate active form^[23]
3-year treatment of woodchuck model of CHB à sustained antiviral efficacy and prolonged life spans without detectable emergence of resistance^[24]
Efficacy # LVD resistant HBV replication in vitro^[25]
Superior activity compared to LVD in vivo for both HBeAg+ & HBeAg− patients^[26]^[27]
Efficacy in LVD refractory CHB patients^[28]
Entecavir was approved by the U.S. FDA in March 2005.

Patent information

Bristol-Myers Squibb was the original patent holder for Baraclude, the brand name of entecavir in the US and Canada. The drug patent expiration for Baraclude was in 2015.^[29]^[30]On August 26, 2014, Teva Pharmaceuticals USA gained FDA approval for generic equivalents of Baraclude 0.5 mg and 1 mg tablets;^[31] Hetero Labs received such approval on August 21, 2015;^[32] and Aurobindo Pharma on August 26, 2015.^[33]

Chronic hepatitis B virus infection is one of the most severe liver diseases in morbidity and death rate in the worldwide range. At present, pharmaceuticals for treating chronic hepatitis B (CHB) virus infection are classified to interferon α and nucleoside/nucleotide analogue, i.e. Lamivudine and Adefovir. However, these pharmaceuticals can not meet needs for doctors and patients in treating chronic hepatitis B virus infection because of their respective limitation. Entecavir (ETV) is referred to as 2′-cyclopentyl deoxyguanosine (BMS2000475) which belongs to analogues of Guanine nucleotide and is phosphorylated to form an active triple phosphate in vivo. The triple phosphate of entecavir inhibits HBV polymerase by competition with 2′-deoxyguanosine-5′-triphosphate as a nature substrate of HBV polymerase, so as to achieve the purpose of effectively treating chronic hepatitis B virus infection and have strong anti-HBV effects. Entecavir, [1S-(1α,3α,4β)]-2-amino-1,9-dihydro-9-[4-hydroxy-3-hydroxymethyl]-2-methylenecyclopentyl]-6H-purin-6-one, monohydrate, and has the molecular formula of C₁₂H₁₅N₅O₃.H₂O and the molecular weight of 295.3. Its structural formula is as follows:

Entecavir was successfully developed by Bristol-Myers Squibb Co. of USA first and the trademark of the product formulation is Baraclude™, including two types of formulations of tablet and oral solution having 0.5 mg and 1 mg of dosage. Chinese publication No. CN1310999 made by COLONNO, Richard, J. et al discloses a low amount of entecavir and uses of the composition containing entecavir in combination with other pharmaceutically active substances for treating hepatitis B virus infection, however, the entecavir is non-crystal. In addition, its oral formulations such as tablet and capsule are made by a boiling granulating process. The process is too complicated to control quality of products during humidity heat treatment even though ensuring uniform distribution of the active ingredients.

Entecavir, [1-S-(1α,3α,4β)]-2-amino-1,9-dihydro-9-[4-hydroxy-3-(hydroxymethyl)-2-methylenecyclopentyl]-6H-purin-6-one, is currently used for treating hepatitis B virus infection, whose structure is composed of a cyclopentane ring having purine, exomethylene, hydroxymethyl, and hydroxy substituents at the 1S-, 2-, 3R-, and 4S-positions, respectively. There have been conducted a number of studies to develop methods for preparing entecavir.

For example, U.S. Pat. No. 5,206,244 and WO 98/09964 disclose a method for preparing entecavir shown in Reaction Scheme 1:

The above method, however, has difficulties in that: i) the cyclopentadiene monomer must be maintained at a temperature lower than -30 °C in order to prevent its conversion to dicyclopentadiene; ii) residual sodium after the reaction as well as the sensitivity of the reaction toward moisture cause problems; iii) the process to obtain the intermediate of formula a) must be carried out at an extremely low temperature of below -70 °C in order to prevent the generation of isomers; iv) a decantation method is required when (-)-Ipc₂BH (diisopinocampheylborane) is used for hydroboration; v) the process of the intermediate of formula a) does not proceed smoothly; and, vi) separation by column chromatography using CHP-20P resin is required to purify entecavir.

WO 2004/52310 and U.S. Pat. Publication No. 2005/0272932 disclose a method for preparing entecavir using the intermediate of formula (66), which is prepared as shown in Reaction Scheme 2:

The above preparation method of the intermediate of formula (66) must be carried out at an extremely low temperature of -70 °C or less, and the yield of the desired product in the optical resolution step is less than 50%.

PATENT

https://patents.google.com/patent/EP2382217B1

Image result for Entecavir

(3-4) Preparation of [1-S-(1α,3α,4β)]-2-amino-1,9-dihydro-9-[4-hydroxy-3-(hydroxymethyl)-2-methylenecyclopentyl]-6H-purine-6-one (a compound of formula (1))

34 mg (0.115 mmol) of 4-(2-amino-6-chloro-purine-9-yl)-2-hydroxymethyl-3-methylene-cyclopentanol (a compound of formula (5)) obtained in (3-3) was added to 0.7 ml of 2N aqueous sodium hydroxide, and the resulting mixture was stirred. The solution thus obtained was heated to 72 °C and stirred for 3.5 hrs. After completion of the reaction, the resulting mixture was cooled to 0 °C, controlled to pH 6.3 by adding 2N aqueous hydrochloric acid and 1N aqueous hydrochloric acid, and condensed to obtain 24 mg of the title compound (yield: 70 %, purity: 99 %).

NMR(300MHz, DMSO-d6): δ 10.58 (s, 1H), 7.67 (s, 1H), 6.42 (s, 2H), 5.36 (t, 1H), 5.11 (s, 1H), 4.86 (d, 1H), 4.83 (t, 1H), 4.57 (s, 1H), 4.24 (s, 1H), 3.54 (t, 2H), 2.53(s, 1H), 2.27-2.18 (m, 1H), 2.08-2.01(m, 1H).

PAPER

https://www.sciencedirect.com/science/article/pii/S0040403911020144

Image result for Entecavir

Image result for Entecavir NMR

PAPER

https://www.sciencedirect.com/science/article/pii/S0040402017313029

Image result for Entecavir NMR

PAPER

Total Synthesis of Entecavir: A Robust Route for Pilot Production

Hua Xu‡, Fang Wang‡, Weicai Xue, Yunjie Zheng, Qi Wang, Fayang G. Qiu^*, and Yehua Jin^*

Launch-Pharma Technologies, Ltd., 188 Kaiyuan Boulevard, Building D, Fifth Floor, The Science Park of Guangzhou, Guangzhou 510530, China

Org. Process Res. Dev., Article ASAP

DOI: 10.1021/acs.oprd.8b00007

Publication Date (Web): February 12, 2018

*E-mail: jinyehua@launch-pharma.com., *E-mail: qiufayang@launch-pharma.com.

A practical synthetic route for pilot production of entecavir is described. It is safe, robust, and scalable to kilogram scale. Starting from (S)-(+)-carvone, this synthetic route consists of a series of highly efficient reactions including a Favorskii rearrangement-elimination-epimerization sequence to establish the cyclopentene skeleton, the Baeyer–Villiger oxidation/rearrangement to afford the correct configuration of the secondary alcohol, and a directed homoallylic epoxidation followed by epoxide ring-opening to introduce the hydroxyl group suitable for the Mitsunobu reaction. In addition, the synthesis contains only four brief chromatographic purifications.

1: white crystalline solid; HRMS (m/z) calcd for C₁₂H₁₆N₅O₃ [M + H]⁺ 278.1253, found 278.1255; [α]_D +27.2° [c 1.07, DMF/H₂O (1:1)];

¹H NMR (500 MHz, DMSO) δ 10.55 (s, 1H), 7.65 (s, 1H), 6.40 (s, 2H), 5.36 (dd, J = 10.3, 8.0 Hz, 1H), 5.10 (s, 1H), 4.85 (d, J = 3.1 Hz, 1H), 4.81 (t, J = 5.3 Hz, 1H), 4.56 (s, 1H), 4.23 (s, 1H), 3.54 (t, J = 6.1 Hz, 2H), 2.55–2.50 (m, 1H), 2.26–2.17 (m, 1H), 2.04 (dd, J = 12.5, 7.8 Hz, 1H);

¹³C NMR (126 MHz, DMSO) δ 156.8, 153.4, 151.4, 151.3, 135.9, 116.2, 109.2, 70.4, 63.0, 55.1, 54.1, 39.2.

Clips

EP 0481754; JP 1992282373; US 5206244, WO 9809964

The regioselective reaction of cyclopentadiene (I) and sodium or commercial sodium cyclopentadienide (II) with benzyl chloromethyl ether (III) by means of the chiral catalyst (-)-diisopinocampheylborane in THF, followed by hydroxylation with H2O2/NaOH, gives (1S-trans)-2-(benzyloxymethyl)-3-cyclopenten-1-ol (IV), which is regioselectively epoxidized with tert-butyl hydroperoxide and vanadyl acetylacetonate in 2,2,4-trimethylpentane, yielding [1S-(1alpha,2alpha,3beta,5alpha)-2-(benzyloxymethyl)-6-oxabicyclo[3.1.0]hexan-3-ol (V). The protection of (V) with benzyl bromide and NaH affords the corresponding ether (VI), which is condensed with 6-O-benzylguanine (VII) by means of LiH in DMF to give the guanine derivative (VIII). The protection of the amino group of (VIII) with 4-methoxyphenyl(diphenyl)chloromethane (IX), TEA and DMAP in dichloromethane gives intermediate (X), which is oxidized at the free hydroxyl group with methylphosphonic acid, DCC and oxalic acid in DMSO or Dess Martin periodinane in dichloromethane, yielding the cyclopentanone derivative (XI). The reaction of (XI) with (i) Zn/TiCl4/CH2Br2 complex in THF/CH2Cl2, (ii) activated Zn/PbCl2/CH2I2/TiCl4 in THF/CH2Cl2 (2), (iii) Nysted reagent/TiCl4 in THF/CH2Cl2 or (iv) Tebbe reagent in toluene affords the corresponding methylene derivative (XII), which is partially deprotected with 3N HCl in hot THF, providing the dibenzylated compound (XI). Finally, this compound is treated with BCl3 in dichloromethane

PAPER

Bioorg Med Chem Lett 1997,7(2),127

BMS-200475, a novel carbocyclic 2′-deoxyguanosine analog with potent and selective anti-hepatitis B virus activity in vitro

BMS-200475, a novel carbocyclic analog of 2′-deoxyguanosine, is a potent inhibitor of hepatitis B virus in vitro (ED₅₀ = 3 nM) with relatively low cytotoxicity (CC₅₀ = 21–120 μM). A practical 10-step asymmetric synthesis was developed affording BMS-200475 in 18% overall chemical yield and >99% optical purity. The enantiomer of BMS-200475 as well as the adenine, thymine, and iodouracil analogs are much less active.

BMS-200475, a novel carbocyclic analog of 2′-deoxyguanosine, is a potent inhibitor of hepatitis B virus in vitro (ED₅₀ = 3nM) with relatively low cytotoxicity (CC₅₀ = 21–120 μM).

PATENT

https://patents.google.com/patent/US20140220120

Fourier transform infrared (FTIR) spectrogram: The range of wave numbers is measured by using the Nicolet NEXUS 670 FT-IR spectrometer with KBr pellet method, and the range of wave numbers is about 400 to 4000 cm⁻¹. FIG. 3 is a Fourier transform infrared spectrogram of the sample. The infrared spectrogram shows that there are groups in the molecular structure of the sample, such as NH, NH₂, HN—C═O, C═C, OH.

PAPER

Total Synthesis of Entecavir

Javier Velasco†‡, Xavier Ariza*†§, Laura Badía‡, Martí Bartra‡, Ramon Berenguer‡, Jaume Farràs*†, Joan Gallardo†, Jordi Garcia†§, and Yolanda Gasanz‡

^† Departament de Química Orgànica and Institut de Biomedicina de la Universitat de Barcelona (IBUB), Facultat de Química, Universitat de Barcelona, Martí i Franquès 1, 08028-Barcelona, Spain

^‡ R&D Department, Esteve Química S.A., Caracas 17-19, 08030-Barcelona, Spain

^§ CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), Instituto de Salud Carlos III, Madrid, Spain

J. Org. Chem., 2013, 78 (11), pp 5482–5491

DOI: 10.1021/jo400607v

*Tel.: +34 934021248. Fax: +34 933397878. E-mail: jfarras@ub.edu, xariza@ub.edu.

Entecavir (BMS-200475) was synthesized from 4-trimethylsilyl-3-butyn-2-one and acrolein. The key features of its preparation are: (i) a stereoselective boron–aldol reaction to afford the acyclic carbon skeleton of the methylenecylopentane moiety; (ii) its cyclization by a Cp₂TiCl-catalyzed intramolecular radical addition of an epoxide to an alkyne; and (iii) the coupling with a purine derivative by a Mitsunobu reaction.

2-Amino-9-((1S,3R,4S)-4-hydroxy-3-(hydroxymethyl)-2-methylenecyclopentyl)-1H-purin-6(9H)-one Monohydrate (1)

1 (2.102 g, 64% overall yield, 99.47% HPLC purity) with a 6.7% water content (as determined by Karl Fischer titration). Mp 248 °C. [α]_D²⁵ +35.0 (c 0.4, H₂O). IR (ATR): 3445, 3361, 3296, 3175, 3113, 2951, 2858, 2626, 1709 cm^–1.

¹H NMR (DMSO-d₆, 400 MHz) δ: 10.59 (s, 1H), 7.66 (s, 1H), 6.42 (bs, 2H), 5.36 (ddt, J = 10.6, 7.8, 2.7 Hz, 1H), 5.10 (dd, J = 2.7, 2.2 Hz, 1H), 4.87 (d, J = 3.1 Hz, 1H), 4.84 (t, J = 5.3 Hz, 1H), 4.56 (t, J = 2.4 Hz, 1H), 4.23 (m, 1H), 3.53 (m, 2H), 2.52 (m, 1H), 2.22 (ddd, J = 12.6, 10.8, 4.6 Hz, 1H), 2.04 (ddt, J = 12.6, 7.7, 1.9 Hz, 1H).

¹³C NMR (DMSO-d₆, 101 MHz) δ: 156.9, 153.5, 151.5, 151.3, 136.0, 116.2, 109.3, 70.4, 63.1, 55.2, 54.1, 39.2. HRMS (ESI): m/z calcd for C₁₂H₁₆N₅O₃⁺ [M + H]⁺ 278.1253; found 278.1262.

PATENTS

JP5788398B2 *2009-10-122015-09-30ハンミ・サイエンス・カンパニー・リミテッドNovel production methods and intermediates used to entecavir

US8481728B22010-02-162013-07-09Scinopharm Taiwan, Ltd.Process for preparing entecavir and its intermediates

CA2705953A1 *2010-05-312011-11-30Alphora Research Inc.Carbanucleoside synthesis and intermediate compounds useful therein

CN106928227A2010-07-152017-07-07浙江奥翔药业股份有限公司Synthetic method of entecavir and intermediate compound thereof

EP2474548A12010-12-232012-07-11Esteve Química, S.A.Preparation process of an antiviral drug and intermediates thereof

EP2597096A12011-11-242013-05-29Esteve Química, S.A.Process for preparing entecavir and intermediates thereof

WO2014175974A32013-03-132015-04-09Elitech Holding B.V.Artificial nucleic acids derived from 2-((nucleobase)methyl)butane-1,3-diol

WO2015051900A12013-10-082015-04-16Pharmathen S.A.Process for the preparation of entecavir through novel intermediates

WO2015051903A1 *2013-10-082015-04-16Pharmathen S.A.A novel process for the preparation of chiral cyclopentanone intermediates

CN103675185B *2013-12-102015-10-07上海景峰制药股份有限公司The method of one kind TU entecavir tablet all-trans isomer by high performance liquid chromatography

KR101647061B12014-04-022016-08-10서강대학교산학협력단Path Generation Method and apparatus for Unmanned Autonomous Vehicle

CN105037363B *2015-07-132016-08-24山东罗欣药业集团股份有限公司En one kind of new synthetic method of compound entecavir

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US5220003A1993-06-15Process for the synthesis of 2',3'-dideoxynucleosides

US5684153A1997-11-04Process for the preparation of purine derivatives

EP1626045A12006-02-15Processes for producing 3-substituted 2-chloro-5-fluoropyridine or salt thereof

WO1996017816A11996-06-13Processes and intermediates for preparing macrocycles

US20060211855A12006-09-21Method for the production of oh protected{4-(2.6-diamino-9h-purine-9-yl)-1.3-dioxolane-2-yl] methanol derivatives

Corey et al.1991An effective system for epoxide-initiated cation-olefin cyclization

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Just et al.1980C-Nucleosides and related compounds. XV. The synthesis of d, l-2′-epi-showdomycin and d, l-showdomycin

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ApplicationPriority dateFiling dateTitle

KR20080134756A2008-12-262008-12-26Process for preparing entecavir and intermediates used therein

PCT/KR2009/0077862008-12-262009-12-24Novel intermediate and process for preparing entecavir using same

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External links

Entecavir
Clinical data


Pronunciation	/ɛnˈtɛkəvɪər/ en-TEK-a-vir or en-TE-ka-veer
Trade names	Baraclude^[1]
AHFS/Drugs.com	Monograph
MedlinePlus	a605028
License data	EU EMA: by INN US FDA: Entecavir
Pregnancy category	AU: B3 US: C (Risk not ruled out)
Routes of administration	by mouth
ATC code	J05AF10 (WHO)
Legal status
Legal status	AU: S4 (Prescription only) CA: ℞-only UK: POM (Prescription only) US: ℞-only
Pharmacokinetic data
Bioavailability	n/a (≥70)^[2]
Protein binding	13% (in vitro)
Metabolism	negligible/nil
Biological half-life	128–149 hours
Excretion	Renal 62–73%
Identifiers
IUPAC name [show]
CAS Number	209216-23-9
PubChem CID	153941
DrugBank	DB00442
ChemSpider	135679
UNII	5968Y6H45M
KEGG	D04008
ChEBI	CHEBI:59902
ChEMBL	CHEMBL713
ECHA InfoCard	100.111.234
Chemical and physical data
Formula	C₁₂H₁₅N₅O₃
Molar mass	277.279 g/mol
3D model (JSmol)	Interactive image
Melting point	220 °C (428 °F) value applies to entecavir monohydrate and is a minimum value^[3]
SMILES [show]
InChI

///////////////Entecavir, энтекавир , إينتيكافير , 恩替卡韦 , BMS-200475, SQ-200475, エンテカビル,

NC1=NC(=O)C2=C(N1)N(C=N2)[C@H]1C[C@H](O)[C@@H](CO)C1=C

NMR PREDICT

1H NMR AND 13C NMR

13C PREDICT VALUES

Avibactam NMR

spectroscopy, Uncategorized Comments Off

Feb 232018

Avibactam, sodium (2S,5R)-2-carbamoyl-7-oxo-1,6-diazabicyclo[3.2.1]octan-6-yl sulfonate,

Avibactam Sodium Salt (1)

white crystalline solid 1 (395.0 g, 96.2%), mp 259.1–262.4 °C (decomposition);

[α]_D²⁰ = −46.40 (c = 0.79, MeOH/H₂O = 1/1);

1H NMR (500 MHz, D₂O) δ 4.15 (dd, J = 5.8, 2.8 Hz, 1H), 4.01 (d, J = 7.5 Hz, 1H), 3.28 (d, J = 12.2 Hz, 1H), 3.06 (d, J = 12.2 Hz, 1H), 2.23–2.09 (m, 1H), 2.06–1.96 (m, 1H), 1.94–1.82 (m, 1H), 1.81–1.69 (m, 1H).

¹³C NMR (126 MHz, D₂O) δ 174.72 (s), 169.53 (s), 60.43 (s), 59.93 (s), 47.33 (s), 20.03 (s), 18.31 (s). IR (cm^–1): 3459, 1749, 1675, 1361, 1270, 1013, 857, 768. MS (ESI) m/z: 279.0 [M + H]⁺.

/////////

Sun Pharma Research Award Winners for 2016, Dr. D. Srinivasa Reddy receives this award for his excellent work in the area of total synthesis of biologically active natural products and medicinal chemistry

award Comments Off

Feb 132018

Dr Reddy (second from left) receives the award from Dilip Shanghvi and Prof Vishwajit Nimgaonkar.

The awards were presented by Prof. Vishwajit Nimgaonkar, Professor of Psychiatry and Human Genetics at the University of Pittsburgh, USA and Mr. Dilip Shanghvi, Managing Director, Sun Pharma

Sun Pharma Science Foundation recognizes Indian scientists for exemplary contribution in pharma & medical science

New Delhi – February 13, 2018: Sun Pharma Science Foundation, a non-profit organization registered under Societies Registration Act announced the Sun Pharma Science Awards to Indian Scientists for their outstanding work and exemplary contribution to medical research.

These awards are presented in two categories – The Sun Pharma Research Awards for outstanding scientists and Sun Pharma Science Scholar Awards for young researchers. The winners for both these awards are identified in two sub-categories – Medical Sciences and Pharmaceutical Sciences. An eminent jury panel comprising well-known scientists from India selected the final winners. These Awards are presented annually to Indian scientists & young researchers working in India and abroad.

The awards were presented by Prof. Vishwajit Nimgaonkar, Professor of Psychiatry and Human Genetics at the University of Pittsburgh, USA and Mr. Dilip Shanghvi, Managing Director, Sun Pharma. Sun Pharma Research Award Winners for 2016 Medical Sciences – Basic Research Award Winner Dr. Rajan Sankaranarayanan Chief Scientist CSIR-Centre for Cellular and Molecular Biology Uppal Road, Hyderabad – 500 007, India Dr. Sankaranarayanan receives this award for his outstanding contributions in the area of protein biosynthesis, by studying proofreading mechanisms using structural biology approaches.

Image result for srinivasa reddy ncl

Dr. D. Srinivasa Reddy Senior Scientist Division of Organic Chemistry CSIR-National Chemical Laboratory Dr. Homi Bhabha Road, Pune 411008, India

Dr. Reddy receives this award for his excellent work in the area of total synthesis of biologically active natural products and medicinal chemistry using “silicon incorporation approach” towards identification of lead molecules of therapeutic potential.

The research interests of his group lie in issues related to application of oriented organic synthesis, in particular total synthesis of biologically active natural products, medicinal chemistry and crop protection. This team has been credited with having accomplished total synthesis of more than 25 natural products with impressive biological activities. “Some of our recent achievements include identification of potential leads, like antibiotic compound based on hunanamycin natural product for treating food infections, anti-diabetic molecule in collaboration with an industry partner and anti-TB compound using a strategy called ‘re-purposing of a drug scaffold’,” said Reddy.

A total of two awardees out of four were from CSIR institutes. In addition to Reddy, Rajan Shankarnarayanan, CSIR – CCMB, Hyderabad (basic sciences), also was conferred with the award. Vikram Mathews, CMC, Vellore (medical research) and Prof Ashish Suri, AIIMS, New Delhi (clinical research), were the others to receive the awards.

With more than 80 scientific publications and 35 patents, Reddy is one of the most prominent scientists in the city and has already been honoured with the Shanti Swarup Bhatnagar prize in chemical sciences. Reddy is also a nominated member of the scientific body of Indian Pharmacopoeia, government of India and was elected as a fellow of the Telangana and Maharashtra Academies of Sciences in addition to the National Academy of Sciences, India (NASI).

About Sun Pharma Science Foundation

Sun Pharma Science Foundation is a non-profit organization registered under Societies Registration Act. It promotes scientific research in the field of Medical and Pharmaceutical Sciences in the country through encouragement and rewarding excellence in research by channelizing both national and international knowledge and expertise. The sole mission of the Foundation is “to promote Medical and Pharmaceutical Research in India by rewarding excellence and identifying sources of knowledge and expertise”. The Sun Pharma Science Foundation is an independent Society managed by an autonomous Governing Council and all the Council Members are independent and have no interest in the commercial activities of SunPharmaceutical Industries Limited. The Foundation is chaired by Prof. Virander S. Chauhan, D Phil (Oxon), J. C. Bose Fellow (DST), Distinguished Biotechnology Research Professor, International Centre for Genetic Engineering and Biotechnology, New Delhi.

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https://www.hindustantimes.com/pune-news/pune-based-scientists-receives-sun-pharma-research-award/story-nEVQaEKGwi7rDnr65VZ38L.html

Design, synthesis and biological evaluation of novel 5-hydroxy-2-methyl-4H-pyran-4-one derivatives as antiglioma agents

drugs, spectroscopy, SYNTHESIS Comments Off

Feb 082018

Design, synthesis and biological evaluation of novel 5-hydroxy-2-methyl-4H-pyran-4-one derivatives as antiglioma agents

Med. Chem. Commun., 2018, Advance Article
DOI: 10.1039/C7MD00551B, Research Article

Yi-Bin Li, Wen Hou, Hui Lin, Ping-Hua Sun, Jing Lin, Wei-Min Chen
Two series of 5-hydroxy-2-methyl-4H-pyran-4-one derivatives were synthesized and their antiglioma activities were evaluated.

Design, synthesis and biological evaluation of novel 5-hydroxy-2-methyl-4H-pyran-4-one derivatives as antiglioma agents

Yi-Bin Li,^a Wen Hou,^a Hui Lin,^a Ping-Hua Sun,^a Jing Lin*^a and Wei-Min Chen*^a

Author affiliations

* Corresponding authors

^a College of Pharmacy, Jinan University, Guangzhou 510632, P. R. China
E-mail: linjing_jnu@163.com, twmchen@jnu.edu.cn
Fax: +86 20 8522 4766
Tel: +86 20 8522 1367

Abstract

D-2-Hydroxyglutarate (D-2HG) is frequently found in human brain cancers. Approximately 50–80% of grade II glioma patients have a high level of D-2HG production, which can lead to cancer initiation. In this study, a series of novel 5-hydroxy-2-methyl-4H-pyran-4-one derivatives were designed and synthesized as antiglioma agents, and their related structure–activity relationships are discussed. Among these novel compounds, 4a exhibited promising anti-proliferative activity against glioma HT1080 cells and U87 cells with an IC₅₀ of 1.43 μM and 4.6 μM, respectively. Further studies found that the most active compound (4a) shows an 86.3% inhibitory rate against the intracellular production of D-2HG at 1 μM, and dramatic inhibitory effects, even at 1 μM on the colony formation and migration of U87 and HT1080 cells.

6,6′-((4-(Benzyloxy)phenyl)methylene)bis(5-hydroxy-2-methyl-4H-pyran-4- one) (4a) The reaction was performed according to the general procedure C, using 1 (1.00 g, 7.90 mmol) and 4-(benzyloxy)benzaldehyde (0.84 g, 3.95 mmol).2 The crude product was recrystallized from isopropanol affording a white powder 4a (1.53 g, 87%): mp 261.4-262.1oC; 1HNMR (300 MHz, DMSO-d6)  2.22 (s, 6H, CH3), 5.08 (s, 3H, OCH2- Ph), 5.96 (s, 1H, CH-Ar), 6.25 (s, 2H, C=CH), , 7.01 (d, J = 9.0 Hz, 2H, Ar-H3’/H5’), 7.22 (d, J = 9.0 Hz, 2H, Ar-H2’/H6’), 7.31-7.45 (m, 5H, Ph-H); 13CNMR (75 MHz, DMSO-d6)  173.95, 165.08, 158.12, 151.20, 147.68, 142.19, 140.77, 137.42, 129.87, 128.91, 128.16, 127.69, 115.46, 114.97, 111.74, 69.69, 19.63; ESI-MS m/z: 447.1 [M+H]+ ; ESI-HRMS m/z: 447.1438 [M+H]+ , calcd for C26H23O7 447.1438.

///////////http://pubs.rsc.org/en/Content/ArticleLanding/2018/MD/C7MD00551B?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FMD+%28RSC+-+Med.+Chem.+Commun.+latest+articles%29#!divAbstract

Unconventional Method for the Synthesis of 3-Carboxyethyl-4-formyl(hydroxy)-5-arylpyrazoles

spectroscopy, SYNTHESIS, Uncategorized Comments Off

Feb 082018

Unconventional Method for Synthesis of 3-Carboxyethyl-4-formyl(hydroxy)-5-aryl-N-arylpyrazoles

Michael J. V. da Silva^†, Julia Poletto^†, Andrey P. Jacomini^†, Karlos E. Pianoski^†, Davana S. Gonçalves^†, Gessica M. Ribeiro^†, Samara M. de S. Melo^†, Davi F. Back^‡, Sidnei Moura^§, and Fernanda A. Rosa^*^†

^† Departamento de Química, Universidade Estadual de Maringá (UEM), 87030-900 Maringá, PR, Brazil

^‡ Departamento de Química, Universidade Federal de Santa Maria (UFSM), 97110-970 Santa Maria, RS, Brazil

^§ Instituto de Biotecnologia, Universidade de Caxias do Sul (UCS), 295070-560 Caxias do Sul, RS, Brazil

J. Org. Chem., 2017, 82 (23), pp 12590–12602

DOI: 10.1021/acs.joc.7b02361

Publication Date (Web): November 2, 2017

*E-mail: farosa@uem.br

Cite this:J. Org. Chem. 82, 23, 12590-12602

Abstract

An alternative highly regioselective synthetic method for the preparation of 3,5-disubstituted 4-formyl-N-arylpyrazoles in a one-pot procedure is reported. The methodology developed was based on the regiochemical control of the cyclocondensation reaction of β-enamino diketones with arylhydrazines.

Structural modifications in the β-enamino diketone system allied to the Lewis acid carbonyl activator BF₃ were strategically employed for this control. Also a one-pot method for the preparation of 3,5-disubstituted 4-hydroxymethyl-N-arylpyrazole derivatives from the β-enamino diketone and arylhydrazine substrates is described.

J. Org. Chem. 2017, 82, 12590

4-Formyl-N-arylpyrazole substrates occupy a prominent position in the field of organic synthesis since they are key intermediates in obtaining a wide range of biologically active compounds. Because of the synthetic versatility of the 4-formyl-N-arylpyrazole skeleton, their synthesis has been extensively explored. In an extension of their previously published research,

Rosa and co-workers at Universidade Estadual de Maringá described a one-pot synthetic method that regioselectively produced 3,5-disubstituted-4-formyl-N-arylpyrazoles . The β-enamino diketone starting materials were readily synthesized via published procedures. High regioselectivity was secured via the use of BF₃·OEt₂ as the carbonyl activator and a bulky amine as the enamine component. Acetonitrile proved to be the most suitable solvent for the reaction.

After an aqueous workup, the desired pyrazoles were obtained in excellent yields. A variety of functional groups were tolerated on the two aryl substituents. This operationally simple procedure afforded the 4-formyl-N-arylpyrazoles in high yields, regioselectively. Furthermore, the formyl group could be reduced in situ with sodium borohydride to generate the corresponding 4-hydroxymethyl-N-arylpyrazoles.

3-(Ethoxycarbonyl)-4-formyl-5-(4-nitrophenyl)-1-phenyl-1H-pyrazole (3a)

Light yellow solid; yield: 0.150 g (82%); mp 147.0–149.2 °C;

¹H NMR (300.06 MHz, CDCl₃) δ (ppm) 1.47 (t, 3H, J = 7.1 Hz, O–CH₂–CH₃), 4.54 (q, 2H, J = 7.1 Hz, O–CH₂-CH₃), 7.19–7.25 (m, 2H, Ph), 7.32–7.43 (m, 3H, Ph), 7.48 (d, 2H, J = 8.9 Hz, 4-NO₂C₆H₄), 8.19 (d, 2H, J = 8.9 Hz, 4-NO₂C₆H₄), 10.57 (s, 1H, CHO);

¹³C NMR (75.46 MHz, CDCl₃) δ (ppm) 14.4 (O–CH₂–CH₃), 62.3 (O-CH₂–CH₃), 122.0 (C4), 123.5 (4-NO₂C₆H₄), 125.9 (Ph), 129.5 (Ph), 129.6 (Ph), 131.8 (4-NO₂C₆H₄), 134.1 (4-NO₂C₆H₄), 137.8 (Ph), 143.5 (C5), 145.0 (C3), 148.4 (4-NO₂C₆H₄), 161.5 (COOEt), 186.6 (CHO);

HRMS (ESI+): calcd for C₁₉H₁₆N₃O₅⁺, [M+H]⁺: 366.1084, found 366.1101.

//////////////https://pubs.acs.org/doi/abs/10.1021/acs.joc.7b02361

A sustainable procedure toward alkyl arylacetates: palladium-catalysed direct carbonylation of benzyl alcohols in organic carbonates

spectroscopy, SYNTHESIS, Uncategorized Comments Off

Feb 082018

A sustainable procedure toward alkyl arylacetates: palladium-catalysed direct carbonylation of benzyl alcohols in organic carbonates

Green Chem., 2018, Advance Article
DOI: 10.1039/C7GC03619A, Communication

Yahui Li, Zechao Wang, Xiao-Feng Wu
A sustainable procedure for the synthesis of various alkyl arylacetates from benzyl alcohols has been developed

A sustainable procedure toward alkyl arylacetates: palladium-catalysed direct carbonylation of benzyl alcohols in organic carbonates

Yahui Li,^a Zechao Wang^a and Xiao-Feng Wu*^a^b

Author affiliations

* Corresponding authors

^a Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert-Einstein-Strasse 29a, 18059 Rostock, Germany

^b Department of Chemistry, Zhejiang Sci-Tech University, Xiasha Campus, Hangzhou 310018, People’s Republic of China
E-mail: Xiao-Feng.Wu@catalysis.de

Abstract

A sustainable procedure for the synthesis of various alkyl arylacetates from benzyl alcohols has been developed. With palladium as the catalyst and organic carbonates as the green solvent and in situ activator, benzyl alcohols were carbonylated in an efficient manner without any halogen additives.

Ethyl 2-phenylacetate

1H NMR (300 MHz, Chloroform-d) δ 7.32 – 7.08 (m, 5H), 4.08 (q, J = 7.1 Hz, 2H), 3.54 (s, 2H), 1.18 (t, J = 7.1 Hz, 3H).

13C NMR (75 MHz, CDCl3) δ 171.61, 134.17, 129.24, 128.54, 127.03, 60.85, 41.45, 14.18.

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