| 摘要 |
NEW MATERIAL:A compound shown by the formula I (R is H or allyl; A is O or methylene; B is methylene, ethylene, or carbonyl) or its salt. EXAMPLE:(1'R,2''S,5R,6S)-2-(1'-hydroxyethyl)-2-(2''-tetrahydrofuranyl) penem-3- carboxylic acid allyl ester. USE:Having extremely excellent effect on remedy of infectious diseases of Gram- positive and Gram-negative bacteria, etc., useful not only as a drug but also as an animal drug widely. PREPARATION:For example, a phosphorus ylide compound shown by the formula II (R<1> is hydroxy-protecting group; R<2> is aryl, or carboxy-protecting group; Z is triarylphosphonio) is heated to give a compound shown by the formula III and optionally the protecting groups R<1> and R<2> are removed to give a compound shown by the formula I. |
