@article{Wang2027, 
author = {Long-Sheng Wang and Zhi-Hong Fang and Zhi-Yi Lu and Pan-Chao Yin and Chun-Lin Lv and Xue-Qiong Wu and Feng-Ping Xiao and Yong-Ge Wei and Hong-Min Li},
title = {Covalent molecular hybridization of heterocyclic hydrazides with hexamolybdates: Structural, electronic, and antitubercular properties},
year = {2027},
journal = {Polyoxometalates},
volume = {6},
number = {2},
pages = {9140142},
keywords = {hydrazide, polyoxometalates, molecular hybridization, antitubercular},
url = {https://www.sciopen.com/article/10.26599/POM.2026.9140142},
doi = {10.26599/POM.2026.9140142},
abstract = {To explore new organically derivatized polyoxymetalates (POMs), three heterocyclic hydrazide-functionalized hexamolybdates—1: (TBA)3[Mo6O18(=N=NCOC5H4N)], 2: (TBA)3[Mo6O18(=N=NCOC4H3S)], and 3: (TBA)3[Mo6O18(=N=NCOC4H3N2)]; (TBA = tetrabutylammonium)—were synthesized by refluxing the corresponding heterocyclic hydrazides with octamolybdates in dry acetonitrile. Their structures were elucidated by single-crystal X-ray diffraction, Fourier transform infrared spectroscopy, ultraviolet–visible spectrscopy, electrospray ionization mass spectrometry, and 1H nuclear magnetic resonance spectroscopy. In all compounds, one terminal oxo atom of the hexamolybdate is replaced by a heterocyclic hydrazide via a Mo=N multiple bond. Compound 1 contains three conformational isomers of [Mo6O18(=N=NCOC5H4N)]3− with approximate Cs or C1 symmetry, whereas compound 2 contains a single [Mo6O18(=N=NCOC4H3S)]3− anion with Cs approximate symmetry. Antitubercular activity assays show that all three compounds exhibit enhanced inhibitory activity compared with hexamolybdate and the thiophene-2-carbohydrazide (L2) ligand, although their activity remains lower than that of isoniazid(L1) and pyrazine-2-carbohydrazide (L3). Given their large molecular weights, the molar inhibitory activities of compounds 1–3 are close to or superior to the corresponding ligands alone. Overall, this work demonstrates that molecular hybridization of organic drug molecules with POMs via covalent bonds provides a promising strategy for developing POM-based agents with enhanced biological activity.}
}