Supramolecular architecture in 1:1 cocrystal of N-carbamothioylacetamide and N,N′-thiocarbonyldiacetamide from the attempted synthesis of 1,3-diacetyl-2-thioxoimidazolidine-4,5-dione (a thioparabanic acid derivative)

An attempt to synthesize thioparabanic acid as precursor to other fused heterocyclic compounds, by a microwave assisted multistep one-pot reaction yielded a co-crystal of N-carbamothioylacetamide (NCTA) and N,N′-thiocarbonyldiacetamide (NNTCA) which is being reported in this paper. The structure of N-carbamothioylacetamide and N,N′-thiocarbonyldiacetamide from the attempted synthesis of 1,3-diacetyl-2-thioxoimidazolidine-4,5-dione, C(5)H(8)N(2)O(2)S.C(3)H(6)N(2)OS, has triclinic (P-1) symmetry. It is of interest with respect to biological application. The structure displays inter- and intra-molecular hydrogen bonding through –C=O···H interactions. Similarly, –C=S···H hydrogen bonding interactions are present, providing additional intermolecular stability to the co-crystal. For application as a potential drug candidate, a density functional theory (DFT) simulation of the antioxidant activities of the co-crystal and its individual components (NCTA and NNTCA) has been performed. The computed redox potentials indicate that the study compounds show comparable antioxidant activities with ascorbic acid (AA) for a one electron transfer process. Meanwhile, for a two-electron process, AA showed significant antioxidant advantage over the titled compound.