VERFAHREN ZUR HERSTELLUNG VON PENICILLINEN UND ZWISCHENPRODUKTEN HIERZU

摘要

The trimethylsilylated compounds of the formula II in which the substituent B2 has the definition given in the patent claim are obtained by reacting 6-aminopenicillanic acid or a known ester thereof with trimethylchlorosilane, as the trimethylsilylating agent, and by subsequent carboxylation, with the addition of urea between the trimethylsilylation and the carboxylation, thereby converting any free organic base still present after the silylation into the corresponding hydrochloride. The products obtained represent valuable precursors for the production of antibacterial, semisynthetic penicillins. <IMAGE>