| 摘要 |
<p>NEW MATERIAL:A compound expressed by formula I [R<1> is H, alkali metal or carboxyl protecting group; R<2> is (substituted)alkyl or heterocyclic]. EXAMPLE:(5S)-3-Thio-8-oxo-1-azabicyclo[3.3.0]octa-2-ene-2-carb-oxylic acid. USE:An antimicrobial agent. PREPARATION:For example, pyrrolidine-2-ones expressed by formula II (L is acyl group, etc.) is reacted with N-acetyl-1,3-thiazoline-2-thiones in the presence of tintrifrate to give a compound expressed by formula III (R<4> is H or alkyl). Then the compound expressed by formula III is treated with Mg malonates to afford a compound expressed by formula IV (R<3> is protecting group), which is then diazotized and treated with copper powder, etc., and subjected to ring closure to give a bicyclo compound expressed by formula V, which is further enolized and the enolized bicyclo compound is reacted with a mercapto reagent to provide the compound expressed by formula I.</p> |
