反应详情

Following a procedure similar to that described in Example 3 but employing 1.6 g. of an isomer mixture comprising 2-[(1-ethyl-2-methyl-3-indolyl)carbonyl]-3-pyridinecarboxylic acid and 3-[(1-ethyl-2-methyl-3-indolyl)carbonyl]-2-pyridinecarboxylic acid, 0.95 g. of N-phenyl-m-toluidine, 0.5 ml. of pyridine and 6 ml. of acetic anhydride there was obtained 7-(1-ethyl-2-methyl-3-indolyl)-7-(m-tolylphenylamino)furo[3,4-b]pyridine-5(7H)-one as a yellow solid, m.p. 178°-190° C. (dec.) A toluene solution of the product contacted with acidic clay or phenolic resin developed an orange image.