Synthesis of 2, 3-Dihydro-2-thioxo-1H-naphth[2, 3-d] imidazole-4, 9-dione Derivativest

Abstract

The reaction of 2, 3-diamino-1, 4-naphthoquinone [2] with potassium xanthogenate gave 2, 3-dihydro-2-thioxo-1 H-naphth [2, 3-d]imidazole-4, 9-dione [3]. Various 2- (2-oxoalkylthio)1 H-naphth[2, 3-d]imidazole-4, 9-diones [4a-k] were obtained by the reactions of [3] with a-halo carbonyl compounds. Compounds [4a-g] were synthesized in water and [4h-k ]were Obtained in the presence of the base using ethanol or water as a solvent. The reaction of [3] with bromoacetaldehyde diethyl acetal afforded sulfide [10], which was easily converted to 3-ethoxy-2, 3-dihydronaphth[2', 3': 4, 5]imidazo[2, 1-b] thiazole-5, 10-dione [11] in the presence of a trace amount of hydrochloric acid. The reaction of [3] with 1, 2-dichloroethane gave 2, 3-dihydronaphth[2', 3': 4, 5]imidazo[2, 1-b]thiazole-5, 10-dione [12] and dimeric compound [13]. The effects of the quinone carbonyl groups on the reaction and properties of these compounds are discussed.