Synthesis and schistosomicidal activity of new substituted thioxo-imidazolidine compounds.

Synthesis and physico-chemical properties of 3-benzyl-5-(4-fluoro-benzylidene)-1-methyl-2-thioxo-imidazolidin-4-ones, 5-benzylidene-3-(4-nitro-benzyl)-2-thioxo-imidazolidin-4-ones and 4-acridin-9-ylmethylene-1-benzyl-5-thioxo-imidazolidin-2-ones compounds are described. These thioxo-imidazolidine derivatives were prepared by alkylation and condensation with 4-fluoro-benzaldehyde or nucleophilic Michael addition with cyanoacrylates. The schistosomicidal activity of 3-benzyl-5-(4-fluoro-benzylidene)-1-methyl-2-thioxo-imidazolidin-4-one compounds was evaluated. Imidazolidine compounds are used for the treatment of schistosomiasis infections. Their efficacy is good but has serious drawbacks (Robinson et al. 1970; Waruiru 1992). This work describes the synthesis and the physicochemical properties of 3-benzyl-5-(4-fluoro-benzylidene)-1methyl-2-thioxo-imidazolidin-4-ones, 5-benzyidene-3-(4nitro-benzyl)-2-thioxo-imidazolidin-4-ones and 4-acridin9-ylmethylene-1-benzyl-5-thioxo-imidazolidin-2-one compounds. These derivatives were synthetised using two different general routes. The first process used was condensation with various benzaldehydes while the second was nucleophilic addition with cyanoacrylates. The synthesis of some 5-aryldene-3-benzyl-4-thioxo-imidazolidin-2-ones and 5-aryldene-1-methyl-2-thioxo-imidazolidin-4-ones has been reported in previous papers (Albuquerque et al. 1999;