Bristol-myers Company

Donald G Walker

Paul R Brodfuehrer

Kun M Shih

Steven P Brundidge

Chet Sapino, Jr

Takayuki Naito

Jun Okumura

Shimpei Aburaki

Yukio Narita

Process for preparing cephalosporin intermediates

Stable, crystalline cephalosporin intermediates of the formula ##STR1## wherein X is HI or HCl and Nu and Nu.sup..sym. are certain N-containing heterocyclic rings attached via a sulfur atom or a ring nitrogen atom, respectively, which are substantially free of the .DELTA..sup.2 isomer; processes for, and intermediates in, the preparation of the above compounds; and processes for the preparation of broad-spectrum cephalosporin antibiotics.

Cephalosporin intermediates

Temperature stable crystalline mono-hydrochloric and sulfuric acid addition salts of 7-amino-3-(1-methylpyrrolidinio)methyl-3-cephem-4-carboxylate substantially free of .DELTA..sup.2 isomer are intermediates for the preparation of broad spectrum 7-[.alpha.-(2-aminothiazol-4-yl)-.alpha.-(Z)-methoxyiminoacetamido]-3-[(1- methyl-1-pyrrolidinio)methyl]-3-cephem-4-carboxylates. The monohydrochloric acid addition salt intermediate is prepared by a process comprising the steps of (1) neutralizing diphenylmethyl 7-amino-3-chloromethyl-3-cephem-4-carboxylate hydrochloride, (2) reacting the resulting free base with benzaldehyde to produce diphenylmethyl 7-benzylideneamino-3-chloromethyl-3-cephem-4-carboxylate, (3) reacting the resulting product with sodium iodide to convert the chloromethyl group to iodomethyl, (4) reacting the resulting product with N-methylpyrrolidine to give the quaternized product diphenylmethyl 7-benzylideneamino-3-(1-methylpyrrolidinio)methyl-3-cephem-4-carboxylate iodide, and (5) reacting with hydrochloric acid to form said intermediate.

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Liverpool, NY, United States of America

Donald G Walker