6-(D-{60 -Amino-p-hydroxyphenylacetamido)-penicillanic acid preparation

摘要

A process for the preparation of 6-(D- alpha -amino-p-hydroxyphenylacetamido)-penicillanic acid or amoxicillin by reacting 6-aminopenicillanic acid with at least two equivalents of a silylating agent producing trimethylsilyl groups in an anhydrous, inert, water-insoluble organic solvent and reacting the resulting product at a temperature below -25 DEG C with an at least equimolar amount of a compound of the formula <IMAGE> III wherein R1 and R7 are lower alkoxy, R2 is lower alkyl and R3 is selected from the group consisting of lower alkyl and hydrogen previously prepared from the corresponding Dane salt and an acid chloride under anhydrous conditions in the presence of a tertiary amine in an inert, water-insoluble organic solvent.