thiourea () is an organosulfur compound with the formula sc(nh). it is structurally similar to urea, except that the oxygen atom is replaced by a sulfur atom, but the properties of urea and thiourea differ significantly. thiourea is a reagent in organic synthesis. "thioureas" refers to a broad class of compounds with the general structure (rrn)(rrn)c=s. thioureas are related to thioamides, e.g. rc(s)nr, where r is methyl, ethyl, etc.