Synthesis, crystal structure, antifungal activities, Hirshfeld surface analysis and molecular docking studies of (2-cycloheptylidenehydrazene-1-carbothioamide) and its complex bis(2-cycloheptylidenehydrazene-1-carbothioamide)Zn(II)

Abstract

Single crystals of (2-cycloheptylidenehydrazene-1-carbothioamide) and its complex bis(2-cycloheptylidenehydrazene-1-carbothioamide)Zn(II) were synthesized. The ligand is in Monoclinic crystal system with empirical formula C8H15N3S and space group P2,1/c with unit cell parameters as a = 12.7532(8) Å, b = 11.7043 (11) Å, c = 13.3287 (9) Å, α = 90°, β = 92.269° and γ = 90° Zinc(II) complex of this ligand [(C8H14N3S)2 Zn] crystallises in Triclinic crystal system with space group P1 and unit cell parameters as a = 8.2143(11) Å, b = 10.2155(13) Å, c = 13.6845(16) Å, α= 84.295(4)°, β= 78.785(4)° and γ= 68.220(4)°. From crystal data analysis, (2-cycloheptylidenehydrazene-1-carbothioamide) exist as a dimer with one cycloheptylidene ring in chair conformation and the second ring in twist chair conformation and for the synthesized Zn(II) complex which is in distorted tetrahedral geometry by geometry index value, one Cycloheptylidene ring is in chair conformation and the other ring is in twist chair conformation. Totally four intermolecular H-bonds are present in the ligand, two of them makes possible the dimeric existence and also one S of each dimer makes other two H-bonds and makes possible the three dimensional arrangement in its lattice structure. From the data of complex, there are two intra molecular H-bonds between C(1)-H—S(1) and C(14)-H—S(2) making the structure rigid and also four inter molecular H-bonds by each carbothioamide moiety of the molecule resulting in a three dimensional sheet like arrangement. Extensive electron delocalisation in carboothiamide moiety of both the molecules are confirmed by the corresponding bond lengths. Both these compounds are proved to be highly promising antifungal agents against the organism Candida Albicans compared to the standard drug Clotrimazole in invitro studies as well as computational docking studies.