4 chloroacetophenone

Thiosemicarbazide, acetophenone, 4-chloroacetophenone, 4-hydroxyacetophenone, 4-methylacetophenone, 4-methoxyacetophenone and 4-nitroacetophenone used for ligand synthesis were purchased from Sigma-Aldrich (USA). Solvents of analytical grade were purchased from E. Merck, and used as received without further purification. Agarose (molecular biology grade) and ethidium bromide were procured from Sigma-Aldrich (USA). Calf-thymus DNA (CT-DNA) and supercoiled pBR322 DNA were purchased from Bangalore Genei (India). Tris(hydroxymethyl)aminomethane-hydrochloride (Tris–HCl) buffer (pH, 7.3) was used for all DNA binding and cleavage studies.
The ligands 2-(1-phenylethylidene)hydrazinecarbothioamide (L¹), 2-(1-(4-tolyl) ethylidene)hydrazinecarbothioamide (L²), 2-(1-(4-methoxyphenyl)ethylidene)hydrazinecarbothioamide (L³), 2-(1-(4-hydroxyphenyl)ethylidene)hydrazinecarbothioamide (L⁴), 2-(1-(4-nitrophenyl)ethylidene)hydrazinecarbothioamide (L⁵) and 2-(1-(4-chlorophenyl)ethylidene)hydrazinecarbothioamide (L⁶) were synthesized by following the procedure as described in the literature.^{26 (link)}