Orally active 2-(alkyloxycarbonyl)-2-alkylideneethyl esters of cephalosporins.

2-(Alkyloxycarbonyl)-2-alkylideneethyl esters of various aminothiazole-oxyimino cephalosporins have been synthesized and studied. They are useful alternatives to the currently existing orally active esters. Among the new esters synthesized, the 3'-azidomethyl cephem ester Ro 41-3399 (7k) presented an oral bioavailability superior to the corresponding pivaloyloxymethyl ester (9) in a rat model and was selected as a candidate for further evaluation.

Ro 13-9904/001, a novel potent and long-acting parenteral cephalosporin.

Ro 13-9904/001 is a novel parenteral cephalosporin antibiotic with potent in vitro activity against a wide range of beta-lactamase-producing and non-producing pathogens. In addition, Ro 13-9904/001 proved to possess a very long plasma half-life and, as a consequence, high prophylactic in vivo effectiveness.