| 摘要 |
NEW MATERIAL:A 3-substituted-4-ethynyl-2-azetidinone derivative shown by the formula I (R<1> is H, or organic residue; R<2> is H, or protective group; R<3> is H, or protective group). EXAMPLE:cis-3-[(R)-1-Hydroxyethyl]-4-ethynyl-2-azetidinone. USE:Useful as an intermediate for synthesizing beta-lactam compounds, especially carbapenem compounds. An intermediate for a 3-substituted-4-acetoxy-2-azetidinone, an important intermediate for thienamycin synthesis. PREPARATION:A reactive derivative of an alkanoic acid alkyl ester shown by the formula II (R<10> is lower alkyl) is reacted with a substituted ethynylaldimine shown by the formula III in an ether solvent at <=-50 deg.C, to give a compound shown by the formula I. |
