Xanthene-9-carbohydrazide derived diorganotin(IV) complexes in persuit to treat bacterial and fungal infections: synthesis, characterization, single crystal X-RD, antimicrobial and DFT studies

Twelve new diorganotin(IV) complexes of the type R₂SnL^1-3 [where R = Me; Et; Bu; Ph, L¹ = N’-1-(2-hydroxy-5-methoxyphenyl)ethylidene)-9H-xanthene-9-carbohydrazide; L² = N’-(1-(2-hydroxyphenyl)ethylidene)-9H-xanthene-9-carbohydrazide; L³ = N’-(1-(5-chloro-2-hydroxyphenyl)ethylidene)-9H-xanthene-9-carbohydrazide] were synthesized and structurally characterized using FT-IR, multinuclear (¹H, ¹³C, ¹¹⁹Sn) NMR spectroscopy, SEM, HRMS, DFT(B3LYP/LanL2DZ) techniques. The in vitro anti-microbial activity was reviewed towards numerous microbes. Data indicated that complexes have more efficacy than ligands and among complexes, complexes 7, 15 and 10, 11 exhibited higher efficacies towards E. coli and C. albicans, respectively. Furthermore, crystal structure of complex 12 was figured out by the single crystal X ray analysis, which confirmed that carbohydrazide bonded with tin atom in a tridentate (ONO) manner. By using DFT, molecular geometry, HOMO-LUMO energy gap, infrared vibrational frequencies, dipole moment, HF energies, Mulliken charges, for the ligand 3 and complexes 12–15 were projected.