| 摘要 |
NEW MATERIAL:Compounds of formula 1a [R<1> is H, alkyl, alkoxy; Ra<2> is alkyl, alkenyl, aralkyl, Ra<5>A-(Ra<5>A is hydroxyl, halogen; A is alkylene); R<3> is H, carboxyl-protecting group] and formula 1b [Rb<2> is alkyl, alkenyl, aralkyl, Rb<5>A-(Rb<5> ?is hydroxyl, alkoxy)] and their pharmacologically permissible salts. EXAMPLE:2-[(2-Aminoethyl)thio]penem-3-carboxylic acid. USE:Antibacterial and its synthetic intermediate. PREPARATION:The reaction of a compound of formula 2 (R<1>' is H, alkyl, R<3>' is carboxyl-protecting group) with another compound of formula 3 (Ra<2>' is alkyl, alkyenyl; X is halogen) or of formula 5 (Rb<2>' is alkyl, alkenyl) to give the compound of formula 4 or 6, from which, when needed, the protecting group is removed to produce the compound of formula 1a or 1b. |
