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

Abstract

During an attempted microwave-assisted one-pot synthesis of thioparabanic acid as a heterocyclic precursor, a 1:1 cocrystal of N-carbamothioylacetamide (NCTA) and N,N'-thiocarbonyldiacetamide (NNTCA) was unexpectedly obtained. The cocrystal adopts triclinic symmetry and is stabilized by both inter- and intramolecular hydrogen bonding via C=O···H and C=S···H interactions. Density functional theory (DFT) calculations were performed to evaluate the antioxidant potential of the cocrystal and its individual components. Computed redox potentials indicated that NCTA and NNTCA exhibit antioxidant activity comparable to ascorbic acid in a one-electron transfer mechanism, whereas ascorbic acid demonstrated a clear advantage in two-electron transfer processes. The findings suggest potential biological relevance of these compounds as antioxidant candidates.

Mechanism

DFT-computed redox potentials indicate that NCTA and NNTCA can donate electrons comparably to ascorbic acid in a one-electron transfer process, suggesting antioxidant capacity through electron transfer mechanisms.