| 摘要 |
<p>An improved process for producing a 7.alpha.-methoxy-cephalo-sporin of the formula wherein R1 and A are as defined hereinafter, or an ester, salt or amide thereof, which comprises reacting a compound of the formula wherein R2 is as defined hereinafter, or an ester, salt or amide thereof, with a halogenating agent in the presence of methanol and an alkali metal salt of methanol and reacting the resulting corresponding 7.alpha.-methoxy compound or an ester, salt or amide thereof, with a thiol of the formula R1--SH or a salt thereof.</p> |
