Pharmacological and Structure-Activity Relationship Evaluation of 4-aryl-1-Diphenylacetyl(thio)semicarbazides

This article describes the synthesis of six 4-aryl-(thio)semicarbazides (series a and b) linked with diphenylacetyl moiety along with their pharmacological evaluation on the central nervous system in mice and computational studies, including conformational analysis and electrostatic properties. All thiosemicarbazides (series b) were found to exhibit strong antinociceptive activity in the behavioural model. Among them, compound 1-diphenylacetyl-4-(4-methylphenyl)thiosemicarbazide 1b was found to be the most potentan algesic agent, whose activity is connected with the opioid system. For compounds from series a significant anti-serotonergic effect, especially for compound 1-diphenylacetyl-4- (4-methoxyphenyl)semicarbazide 2b was observed. The computational studies strongly support the obtained results

1-(3-Chloro­phen­yl)-3-(1-p-tolyl­imidazolidin-2-yl­idene)urea

In the crystal structure of the title compound, C17H17ClN4O, the existence of only one 2-imino–oxo of the five possible N-amino–imino/O-keto–hydr­oxy tautomers is observed and the dihedral angle between the aromatic rings is 29.78 (11)°. The mol­ecular conformation is stabilized by intra­molecular C—H⋯N, N—H⋯O and C—H⋯O hydrogen bonds, in each case generating a six-membered ring. In the crystal structure, the glide-plane-related mol­ecules are linked into C(4) amide chains by inter­molecular N—H⋯O hydrogen bonds, and an inter­molecular C—H⋯O link also occurs