Pyridine → Diphenylmethyl 3-acetoxymethyl-7beta-[2-(4-nitrobenzoyloxyimino)-2-phenylacetamido)ceph-3-em-4-carboxylate

Participants

Reaction Steps

To a solution of diphenylmethyl 3-acetoxymethyl-7β-(2-hydroxyimino-2-phenylacetamido)ceph-3-em-4-carboxylate (syn-isomer) (1.5 g.) and pyridine (0.5 ml.) in ethylacetate (100 ml.) was added 4-nitrobenzoyl chloride (0.42 g) and the resulting solution was stirred at room temperature for one hour. Further portions (0.042 g 0.015 g and 0.20 g.) of the acid chloride were added, and the reaction stirred for a total of 4 hours at room temperature. Then the solution was washed with 2 N-hydrochloric acid and brine, dried, concentrated to ca. 5 ml. and added dropwise with stirring to petroleum spirit (b.p. 40°-60°). This gave a solid which was filtered and dried, yielding the title ester (1.1 g; 58%), λmax. (EtOH) 263 nm (ε 29,000), νmax. (CHBr3) 3400 (NH), 1780 (β-lactam), 1395 and 1525 (NO2), 1687 and 1515 cm.- 1 (CONH), τ (CDCl3) values include 1.70 and 2.71 (two doublets, J 8 Hz; ##STR33## 2.1-2.85 (multiplet; aromatic protons), 8.03 (singlet; OCOCH3)

Provenance & Evidence