A process for the preparation of compounds of formula (I) ##STR1## wherein R.sub.1 is hydrogen or an organic group; R.sub.2 is hydrogen or a carboxy protecting group; and Y is a group-S-heterocyclic, acyloxy, alkoxy, alkylthio, pyridyl, which group may be substituted, or azido, and penem derivatives falling within the scope of formula (I) and pharmaceutically or veterinarily acceptable salts thereof. The process involves displacing a group L in the Y position with a reagent Y-H.
一种制备式(I)化合物的方法,其中R1为氢或有机基团;R2为氢或羧基保护基团;Y为-S-杂环、酰氧基、烷氧基、烷基
硫基、
吡啶基,该基团可能被取代,或者是
叠氮基,
茚香烷衍
生物属于式(I)的范围内,以及它们的药学或兽医学可接受的盐。该方法涉及用试剂Y-H取代Y位置的基团L。