| 摘要 |
<p>A process for the preparation of a penam derivative of formula (I): <CHEM> wherein R is phenyl, p-hydroxyphenyl, p-(C1-6)-alkyl-carbonyloxyphenyl or 2- or 3-thienyl, R<1> is hydrogen, or a pharmaceutically acceptable salt-forming ion or ester-forming radical, and R2 represents hydrogen or a pharmaceutically acceptable salt-forming ion or in vivo hydrolysable ester-forming radical; which process comprises reacting a suitably protected 6, alpha arylthio derivative with methanol in the presence of either: (a) silver, thallium or mercuric ions; or (b) chlorine and a base; and thereafter if necessary removing the protecting groups, and converting the product to a pharmaceutically acceptable salt or ester thereof.</p> |
