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US 3,978,078 AGranted
Process for the preparation of ampicillin
AssigneeRhone-Poulenc Inc.
InventorsJean Bouchaudon, Pierre Le Roy, Mayer Naoum Messer
Life of this patent
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Abstract
Ampicillin is prepared by reacting an inorganic or organic base with a new penicillin G derivative of the formula: ##EQU1## (wherein R.sub.1 represents a group protecting the carboxy radical and R.sub.2 represents a strong electron-attracting group, e.g. a halogenoethyl group) to open the imidazolidine ring and give an intermediate product of the formula: ##EQU2## and removing by methods known per se the groups --R.sub.1 and R.sub.2 O--CS-- which protect the carboxy radical and amine functions respectively.
Claims6
A penicillin G derivative of the formula:
- ##EQU3## wherein R.sub.1 is a group selected from the class consisting of benzyl, p-nitrobenzyl, 2,2,2-trichloroethyl, trityl, dimethylsilyl, trimethylsilyl, phenacyl, p-bromophenacyl, acetyl, propionyl, butyryl, benzoyl, succinyl, methanesulphonyl, p-toluenesulphonyl, methylphosphinyl, methoxyphosphinyl, dimethylphosphinyl, dimethoxyphosphinyl, chloroethoxyphosphinyl, dichloroethoxyphosphinyl, phenylphosphinyl, phenoxyphosphinyl, diphenylphosphinyl, diphenoxyphosphinyl, 4-methyl-1,3,2-dioxaphosphoranyl, 1,3,2-dioxaphosphiranyl and 1,3,2-benzodioxaphospholyl, Y is halogen, n is zero, 1 or 2, and R is hydrogen or phenyl.
Dependencies are inferred from the claim text.