Dimethyl Sulfoxide → 10-methyl-2,3-dihydro-1H-pyrrolo[2,1-c][1,4]benzodiazepine-5,11(10H,11aH)-dione

Participants

Reaction Steps

A mixture of 12.3 g. of L-proline, 17.7 g. of N-methyl isatoic anhydride and 100 ml. of dimethyl sulfoxide is heated on a steam bath for 40 minutes. The mixture is cooled and diluted with 250 ml. of cold water. The precipitate is recovered by filtration, washed with water and then ether, air dried and then recrystallized from ethanol yielding the intermediate L-1-(N-methylanthraniloyl)proline, melting point 140°-142° C., [α]D25 -165° C. (1.1%, methanol).

Provenance & Evidence