Transformation of bromhexine, a mucolytic drug into potential pharmacologically important urea derivatives

A general synthesis for 1,3-diphenylurea and 1,3-diphenylthiourea derivatives of mucolytic agent bromhexine is described by reactions of different commercially available phenyl isocyanates and phenyl-isothiocyanates at room temperature without any additional catalyst and additive. Using commercially available electron donating and electron withdrawing phenyl isocyanates in the transformation of bromhexine into urea derivatives proceeded from moderate to high product yield (42-90%). Bromhexine resulting compounds add a general interest in the fields of Pharmaceuticals, diagnostics and materials.