| 摘要 |
A chemical process for the production of isoxazolyl penicillins and nontoxic salts and lower alkyl esters thereof having the formula REQUIRES NO MICROBIOLOGICAL DEACYLATION OR FERMENTATION TO PRODUCE 6-AMINOPENICILLANIC ACID, BUT INSTEAD COMPRISES REACTING A PENICILLIN G ester having the formula WHEREIN R' is a protective group for carboxyl group and is selected from the group consisting of lower alkyl and a group which, when subjected to an elimination reaction, can be easily eliminated without having any detrimental effect on the structure of penicillin, which a chlorinating agent in the presence of a tertiary organic base to obtain an imide chloride group-incorporated compound having the formula WHEREIN R' is as defined above; reacting the compound of Formula III with an isoxazol carboxylate having the formula WHEREIN M is a metal atom, and R1 and R2 are as defined above, to obtain a diacyl penicillin ester having the formula WHEREIN R1, R2 and R' are as defined above; then subjecting the compound of Formula V to dephenylacetylation; and eliminating R' when R' is a said easily eliminated group.
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