Synthesis, Spectral, Thermal, and Biological Studies of Adducts of Organotin(IV) Halides with Schiff Bases Derived from 2-Amino-5-(o-methoxyphenyl)-1,3,4-thiadiazole

Abstract

Some new organotin(IV) complexes of the general formula, RnSnCl4−n·L [where n = 3, R = CH3 or C6H5; n = 2, R = C6H5; L = Schiff bases derived from the condensation of 2-amino-5-(o-methoxyphenyl)-1,3,4-thiadiazole with salicylaldehyde (L-1), 2-hydroxy-1-naphthaldehyde (L-2), 2′-hydroxyacetophenone (L-3), benzyl methyl ketone (L-4), acetylacetone (L-5), and 2-furancarbaldehyde (L-6)] have been synthesized and characterized by elemental analyses, molar conductances, electronic, infrared, far-infrared, 1H and 119Sn NMR and Mössbauer spectral studies. Thermal studies of three complexes, viz., Ph3SnCl(L-2), Me3SnCl(L-4), and Ph3SnCl(L-5) have been carried out in the temperature range 25—1000 °C using TG, DTG, and DTA techniques. All these complexes decompose gradually with the formation of SnO2 as an end product. In vitro antimicrobial activity of the ligands and their complexes has also been determined against Streptococcus faecalis, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus Penicillin resistance (2500 units), Candida albicans, Cryptococcus neoformans, Sporotrichum schenckii, Trichophyton mentagrophytes, and Aspergillus fumigatus.

Synthesis, characterization and thermal behavior of some Zn(II) complexes with ligands having 1,3,4‐thiadiazole moieties

“…In the spectra of the [Zn 2 (L 3 ) 2 (H 2 O) 4 Cl 4 ] complex, the ν(>C N N C<) vibrations remain almost unchanged indicating, thereby, noninvolvement of the ring nitrogen in-coordination. The ν(C S C) undergoes a negative shift in the complex, indicating the coordination of ring sulfur to copper [4].…”

“…In the spectra of the [Zn 2 (L 3 ) 2 (H 2 O) 4 Cl 4 ] complex, the ν(>C N N C<) vibrations remain almost unchanged indicating, thereby, noninvolvement of the ring nitrogen in-coordination. The ν(C S C) undergoes a negative shift in the complex, indicating the coordination of ring sulfur to copper [4]. The coordination through the azomethine nitrogen and sulfur is further supported by the occurrence of new bands at 460 and 360 cm −1 in the spectra of the complex, which may be assigned to ν(M → N) and ν(S → M) vibration, respectively [23,24].…”

“…Electronic spectral studies were conducted on a Shimadzu model UV-1700 spectrophotometer in the wavelength 1100-200 nm. Magnetic susceptibilities measurements were performed using the standard Gouy tube technique using Hg[Co(SCN) 4 ] as a calibrant. Thermal analyzers (TGA and DTA) were carried out in nitrogen atmosphere with a heating rate of 15…”

“…The azomethine ν(C N) bands in the spectra of ligand L 3 lying at 1676-1624 cm −1 displayed a shift to lower wave numbers (1660-1612) in the spectra of [Zn 2 (L 3 ) 2 (H 2 O) 4 Cl 4 ] complex, indicating that the C N nitrogen atom coordinates to the metal ion in this complex [18].…”

“…Since the first preparation of thiadiazole, numerous research investigations have focused on thiadiazoles and their derivatives. It is known that the thiadiazole themselves and their derivatives have been used as antibacterial, antifungal, insecticidal [4,5], herbicidal, pesticidal, and antitumor agents [6,7]. The ligands used in this work (Figs.…”