| abstract |
NEW MATERIAL:A methine compd. of formula I (wherein R 1 is alkyl, aryl, alkoxy, alkoxycarbonyl, aryloxycarbonyl, acyl, hydroxyl, etc.; R 2 is aryl or benzyl; R 3 and R 4 are each H, alkyl, aryl, or alkoxycarbonyl; Z is a nonmetallic atom needed for forming a 5-membered heterocyclic ring; (n) 0 or 1; and L 1 , L 2 , and L 3 are each methine) n USE: Useful as a dye, a dye for a silver halide photosensitive material, a recording compd. for an optical information recording medium, a dye for dyeing a living organism such as a cell, a medicine, etc. n PREPARATION: A compd. of formula II and a compd. of formula III are subjected to the condensation by dehydration in an org. solvent, if necessary, in the presence of a catalyst such as acetic acid or triethylamine, to give a methine compd. of formula I. n COPYRIGHT: (C)1991,JPO&Japio |