Synthetic, structural and biological studies of organotin(IV) complexes of schiff bases derived from pyrrol-2-carboxaldehyde

Abstract

Some new organotin(IV) complexes having general formulae R 2 MCl[L] and R 2 M[L] 2 were synthesized by the reactions of Me 2 MCl 2 with Schiff bases [5-Mercapto-4-(pyrrolcarboxalideneamino)-s-triazole, 5-Mercapto-3-methyl-4-(2-pyrrolcarboxalideneamino)-s-triazole, 3-Ethyl-5-mercapto-4-(2-pyrrolcarboxalideneamino)-s-triazole] in 1:1 and 1:2 molar ratios. All of the compounds were characterized by elemental analysis, molar conductance, IR, UV, 1 H, 13 C and 119 Sn NMR spectral studies. The IR and 1 H NMR spectral data suggest the involvement of azomethine nitrogen in coordination with the central metal atom. With the help of the above-mentioned spectral studies, penta and hexacoordinated environments around the central metal atoms in the 1:1 and 1:2 complexes, respectively, have been proposed. Finally, the free ligands and their metal complexes were tested in vitro against some pathogenic bacteria and fungi to assess their antimicrobial properties.

Biological and Spectral Studies of Newly Synthesized Triazole Schiff Bases and Their Si(IV), Sn(IV) Complexes

“…These bands show a blue shift in 1 : 1 and 1 : 2, Si(IV) and Sn(IV) metal complexes and appear at 368 nm, 369 nm, 358 nm, 369 nm, 362 nm, 364 nm, 359 nm, 362 nm, 372 nm, 368 nm, 376 nm and 366 nm for Me 2 SiCl(L 1 ), Me 2 Si(L 1 ) 2 , Me 2 SnCl(L 1 ), Me 2 Sn(L 1 ) 2 , Me 2 SiCl(L 2 ), Me 2 Si(L 2 ) 2 , Me 2 SnCl(L 2 ), Me 2 Sn(L 2 ) 2 , Me 2 SiCl(L 3 ), Me 2 Si(L 3 ) 2 , Me 2 SnCl(L 3 ), and Me 2 Sn(L 3 ) 2 , respectively, and indicating the coordination of azomethine nitrogen atom to the metal atom [ 16 ]. In addition to this, the three medium intensity bands at 244 nm, 240 nm, and 260 nm due to π - π * transition in the ligands remain unchanged or show a minor change in the spectra of metal complexes [ 17 ].…”

“…The 13 C NMR spectral data of ligands HL 1 , HL 2 , and HL 3 , and their corresponding 1 : 1 and 1 : 2 metal complexes [ 17 , 18 ] have been reported in Table 4 . The signal due to the carbon atom attached to the azomethine group in the ligands HL 1 , HL 2 , and HL 3 appear at δ 166.42 ppm, δ 162.23 ppm, and δ 160.79 ppm, respectively.…”

“…Ahmad et al have also screened some organotin compounds against tumor cells [ 16 ]. Prompted by these applications, few new organosilicon and organotin compounds have already been synthesized and screened for antibacterial and antifungal activities [ 17 , 18 ], and in continuation to this, in the present paper, the synthesis, characterization, and biological activities of new triazole Schiff bases and their organosilicon and organotin complexes have been carried out.…”

The structure–activity relationship of some hexacoordinated dimethyltin(IV) complexes of fluorinated β‐diketone/β‐diketones and sterically congested heterocyclic β‐diketones

“…Diorganotin(IV) complexes attract considerable interest in biological applications owing to their use as antineoplastic agents . Organotin(IV) complexes of β‐diketones, heterocyclic β‐diketones, Schiff bases, oximes, amino acid derivatives, sulfa drug derivatives, etc., have been cited in the literature due to their potential industrial and biological applications . 5‐Pyrazolone ligands are used as pharmaceutical agents and exhibit anti‐inflammatory as well as antioxidant properties.…”