[Relationship between structure and in vitro antifilarial activity of twenty-four 3- and/or 4-substituted nitrofuran compounds].

The effects of 24 derivatives of nitrofurazone, nitrofurantoin, furazolidone and furapyrimidone on microfilariae and macrofilariae in vitro were tested. When -CH3, -OCH3 or -OC2H5 was introduced into 3- or/and 4-position of nitrofuryl ring, the antimicrofilarial effects of these derivatives decreased markedly as compared with their corresponding parent compound. While Br or Cl substituted derivative enhanced the antimicrofilariae action. Same results were observed when the above derivatives of furapyrimidone were tested against adult worms in vitro.