10.1016/j.ica.2010.05.009
The study focuses on the synthesis and characterization of five new Ni(II) complexes with aroyl hydrazone ligands derived from 2,6-diacetyl pyridine monooxime. The complexes were found to have a distorted octahedral N4O2 coordination environment around the Ni(II) ion, with the ligands coordinating through the pyridine nitrogen, imino-hydrazone nitrogen, and the deprotonated oxygen of the hydrazone moiety. The uncoordinated iminooxime groups and the orthogonal orientation of the CH3–C@N–OH groups relative to the adjacent pyridine rings were observed. The ligands and their corresponding Ni(II) complexes exhibited luminescence, with the complexes showing a lower quantum yield compared to the free ligands. The study also includes the X-ray crystal structure of the Ni(II) salicyloylhydrazone complex, which revealed details about the molecular structure and hydrogen bonding interactions in the crystal lattice. The research provides insights into the coordination chemistry of aroyl hydrazone ligands and their potential applications in areas such as pharmaceuticals and materials science.
10.1016/j.bmc.2011.04.033
This study investigates the synthesis and antimycobacterial activity of novel hybrid compounds against Mycobacterium tuberculosis (MTB). The study employs a chemoselective 1,3-dipolar cycloaddition reaction to generate 1,2,4-oxadiazole-pyranopyridine and 1,2,4-oxadiazole-chromene hybrids from 2-aminopyranopyridine-3-carbonitriles and 2-aminochromene-3-carbonitriles, respectively. The synthesized compounds were evaluated for their in vitro antimycobacterial activity against MTB H37Rv strain. The results revealed that the 1,2,4-oxadiazole-pyranopyridine hybrids exhibited enhanced activity compared to the 1,2,4-oxadiazole-chromene hybrids. Notably, compound 5h demonstrated superior potency, being 1.2, 15.2, and 24.6 times more active than the standard drugs isoniazid, ciprofloxacin, and ethambutol, respectively.