| 摘要 |
1,213,571. Cephalosporins. BRISTOLMYERS CO. 5 Jan., 1968 [5 Jan., 1967], No. 871/68. Heading C2A. The invention comprises an α-pyridylthioacetamido cephalosporanic acid derivative of formula wherein A is H, OH, C 2-8 alkanoyloxy, benzyloxy, a quaternary ammonium radical especially pyridinium, quinolinium, picolinium or lutidinium, or, when taken together with M is a monovalent C-O bond; and M is H, a pharmaceutically acceptable non-toxic cation, an anionic charge when A is a quaternery NH 4 radical or, when taken together with A, is a monovalent C-O bond; and Z is 2,- 3,- or 4- pyridyl. The compounds are prepared by (a) reacting a compound of formula: wherein A and M have the above meaning, with an α-haloacetyl halide of formula in which Hal is chloro, bromo or iodo, or its functional equivalent as an acylating agent, in the presence of a base, to produce an α- haloacetamido compound of formula wherein A and M are as defined above, and (b) reacting the thus-prepared α-haloacetamido compound in the presence of a base with a mercaptan of formula Z-SH wherein Z has the above meaning. Salts are formed with inorganic cations e.g. sodium and potassium, organic amine cations e.g. triethylamine, procaine and N-ethylpiperidine and with inorganic acids e.g. hydrochloric and organic acids e.g. acetic and ascorbic. Typical compounds are 7-[a-(4-pyridylthio)-acetamido]cephalosporanic acid and 3-methyl-7-[α-(4-pyridylthio) acetamido-]-3-cephem-4-carboxylic acid monophosphate. The 3- and 4-pyridyl compounds are more active against gram-negative bacteria than the 2-pyridyl compound. A pharmaceutical composition for parenteral or oral administration to man and animals comprises an α-pyridylthio acetamido cephalosporanic acid of Formula I and a carrier. The compositions may be used for treating mastitis in cattle. The compounds may be used as nutritional supplements in animal feeds. |
