benzhydryl (6R,7R)-7-[[(2Z)-2-(2-amino-5-chloro-1,3-thiazol-4-yl)-2-trityloxyiminoacetyl]amino]-3-chloro-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate → benzhydryl (6R,7R)-7-[[(2Z)-2-(2-amino-5-chloro-1,3-thiazol-4-yl)-2-trityloxyiminoacetyl]amino]-8-oxo-3-sulfanyl-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate

Participants

Reaction Steps

To a solution of (7R)-7-[(Z)-2-(2-amino-5-chlorothiazol-4-yl)-2-(tripheny lmethoxyimino)acetamido]-3-chloro-3-cephem-4-carboxylate diphenylmethyl ester (4.0 g, 4.72 mmol) in DMF (30 mL) cooled to -20°C. was added in one portion powdered sodium hydrogen sulfide hydrate (1.1 g, 19.6 mmol). After 15 min the reaction mixture was poured into 0.5 M monosodium phosphate (about 100 mL), extracted with ethyl acetate and the organic layer was washed thoroughly with water. After concentrating in vacuum the crude title product was obtained as yellow foam 3.8 g (95%). 1H NMR (CDCl3 /CD3OD) δ3.38 (d, 1H, J=15) 4.43 (d, 1H, J=15), 5.03 (d, 1H, J=5), 5.80 (d, 1H, J=5), 5.99 (br s, 1H), 6.80 (s, 1H), 7.05-7.50 (m, 25H).

Provenance & Evidence