Synthesis, characterization, x-ray structure and antimicrobial activity of N-(4-chlorophenyl)-2-(pyridin-4- ylcarbonyl) hydrazinecarbothioamide

Purpose: To synthesize thiosemicarbazide and determine its antimicrobial properties.
Methods: Pyridine-based thiosemicarbazide was synthesized, characterized and evaluated for antimicrobial activity. The structure of the synthesized compound was established by spectral analysis, namely, Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (1H NMR), carbon 13 magnetic resonance spectroscopy (13C NMR), liquid chromatography-mass spectroscopy (LC-MS), single crystal x-ray analysis as well as by elemental analysis.
Results: The title compound crystallized in monoclinic form with space group P2_1/c of a = 11.6050 (3) Å, b = 13.3130 (4) Å, c = 9.9884 (3) Å, β = 94.911 (2)°, V = 1537.52 (8) Å3, Z = 4 and R_int = 0.033. The pyridine ring formed dihedral angles of 74.1(3) and 88.2(5)° with major and minor components of disordered benzene ring, respectively. In the crystal packing, molecules were linked via intermolecular N—H•••N, N—H•••S and N—H•••O hydrogen bonds into zigzag layers. Compound 2 was most effective against Bacillus subtilis ATCC 10400, MRSA 85N, MRSA 66N and MRSA 15G, compared to the reference drugs, ampicillin and ceftriaxone.
Conclusion: The title compound represents a good lead for the development of potent antibacterial agent against Gram positive bacteria and MRSA strains.

Keywords
Isoniazid; Thiosemicarbazide; Single crystal x-ray; Antimicrobial activity