[Synthesis of acylates of niridazole and its analogs as schistosomicides]

In order to decrease the toxicity and enhance the curative effect of niridazole against Schistosomiasis japonica, a series of acylates of niridazole has been prepared through acylation of niridazole, 2-substituted acetamido-5-nitrothiazoles and 1-(5-nitro-2-thiazolyl)-4-acylpiperazine were also prepared. The products has been tested against Schistosomiasis japonica in mice. Preliminary test results showed that the majority of aliphatic acylates of niridazole exhibited marked schistosomicidal effect against adult worms as well as larva (compounds 2, 4-8, 12, 13, 15, 18, 19), a few of aromatic and heterocyclic acylates (compounds 14, 22) and the analogs of niridazole (compounds 26, 39, 49) showed weak activity.