摘要 |
<p>6-Alkoxylated-6-acylamidopenicillanic acids and 7-alkoxylated-7-acylamidocephalosporin acids and esters thereof, are provided by reacting a 6-acylamidopenicillanic acid ester or a 7-acylamidocephalosporin ester under anhydrous conditions at -90 DEG C. to -15 DEG C. with an alkali metal salt of a lower alkyl alcohol in the presence of an excess of the corresponding alcohol to produce, in situ, the anionic form of the antibiotic which on halogenation with a positive halogen compound, e.g. t-butyl hypochlorite, yields the compound of the invention. Compounds of the invention, e.g. 6-methoxy-6-phenoxyacetamidopenicillanic acid and 7-methoxy-7-[2-(2-thienyl)acetamido]cephalosporanic acid are useful antibiotics.</p> |