| abstract |
PURPOSE:To obtain the titled useful compound having improved inhibitory action on platelet aggregation in high yield and efficiently, by condensing a 1-substituted indole derivative with a carboxylic acid anhydride in the presence of hydriodic acid as a catalyst. CONSTITUTION:A 1-substituted indole derivative of formula I [R1 and R6 are H or lower alkyl; R2, R3, R4 and R5 are H, OH, halogen, lower alkoxyl and alkanoyloxy, etc.; however, R2 and R3, R3 and R4, R4 and R5 together form methylene and ethylenedioxy; n is 0 or an integer 1-5; X is formula II (R7 is H or lower alkyl; R8 is lower alkyl, etc.) or formula III (R9 is lower alkoxyl, etc.) is condensed with a carboxylic acid anhydride of formula IV (phi is aromatic, hetero cyclic, alicyclic group, etc.) in the presence of hydriodic acid at 80-150 deg.C for 1- 6hr, and if necessary hydrolyzed to give the aimed compound of formula V [X' is formula VI (R8' is H, lower alkyl, etc.), etc.]. USE:Prevention of infarction in cardiovascular systems, etc. |