Alpha-1-p-chlorobenzoyl-2-methyl-5-methoxyindolyl-3

摘要

Preparation of the 3-indolylacetic acid derivative of the formula (I):- The method is superior to the previously described method for the preparation of the compound (I) (U.S.Patent 3, 161, 654). 3.7 g. alpha(1-p-chlorobenzoyl-2-methyl-3-amino-indolyl-(3)) acetic acid hydrochloride in 50 ml. methanol is mixed with 1.2 g. methyl nitrite and heated for one hour in a glass autoclave at 90-100 deg.C. The system is then cooled to 0 deg.C and the pressure is allowed to drop to atmospheric pressure. The solvent is then removed in vacuum to give a solid residue consisting of alpha(1-p-chlorobenzoyl-2-methyl-5-methoxy-indolyl-(3)) acetic acid.