ORGANIC COMPOUNDS AND THEIR PREPARATION

摘要

1,269,279. Azetidinones. BEECHAM GROUP Ltd. 20 July, 1970 [29 July, 1969], No. 37977/69. Heading C2C. Novel compounds I (including acid addition salts thereof and stereoisomers) where R is optionally substituted alkyl, aralkyl O alkenyl, R1 is H, or optionally substituted alkyl, aralkyl or aryl or a salt forming ion, R2 is H or optionally substituted aralkyl or acyl and R3 is H or optionally substituted aralkyl, are made by reacting penicillanic acid derivatives (II), in anhydrous liquid medium, with a strong base which does not cleave the #-lactam ring, and with an alkylating, aralkylating or alkenylating agent to introduce R; II are such that the products I are those where R2 is aralkyl (removal of aralkyl, e.g. trityl is conveniently removed utilizing p-toluene-sulphonic acid, affords I where R2 is H; subsequent acylation affords I, where R2 is acyl) and R1 is alkyl, aralkyl or aryl (catalytic hydrogenation or hydrolysis accordingly affords the free acids I). The starting materials (II), e.g. benzyl and pmethoxybenzyl 6 - # - (triphenylmethylamino) penicillanates, are prepared, e.g. by the tritylation of the appropriate 6-aminopenicillanic acid esters.