Preliminary in vitro Cytotoxic Assay on HepG2 and Antibacterial Screening Activity: Synthesis and Characterization of Organotin(IV) Complexes Derivatives of 2-Methyl-3-nitrobenzoic Acid

Abstract

Three organotin(IV) carboxylate complexes derivatives of 2-methyl-3-nitrobenzoic acid (HL) have been successfully synthesized and characterized quantitatively and qualitatively. The complexes obtained are screened for their preliminary in vitro cytotoxic assay on human liver hepatocellular carcinoma cells (HepG2) and antibacterial screening activity. Results of the infrared and NMR spectroscopy on the acid and complexes showed that the coordination took place via oxygen atoms from the carboxylate anions. With the exceptional case, based on the spectroscopy studies indicated that one methanol molecule also take part in the coordination to tin(IV) atom moiety in complex 3 resulting the tin(IV) atom exhibited five coordination in solid state. From the preliminary in vitro cytotoxic assay on HepG2 and antibacterial screening activity, triphenyltin(IV) (complex 3) showed slightly better activity compared to diorganotin(IV) complexes (1 and 2).

Synthesis, crystal structures and spectroscopic properties of two new organotin (IV) complexes and their antiproliferative effect against cancerous and non-cancerous cells

“…Evidences of the formation of the complexes were further observed in the 13 C-NMR spectra. The 13 C-NMR spectra of complexes 1-2 showed that the d(COO) signals shifted to the downfield region compared to that of the acid, HL indicating the carboxylate anion were bonded to tin(IV) atoms.…”

“…The infrared spectra were recorded using a Perkin-Elmer System 2000 FTIR Spectrophotometer as a KBr disc in the frequency range of 4000-400 cm À1 . The spectra for 1 H, 13 C and 119 Sn-NMR were recorded on a Joel JNM-ECX 400 FT-NMR Spectrometer using deuterated d 6 -DMSO as the solvent and tetramethylsilane, TMS as the internal standard.…”

“…Hence, the carboxylate anion in complex 2 would be expected to bond to the tin(IV) atom in monodentate manner since the Dn is 3.3. Characterization by 1 H, 13 C, 119 Sn-NMR spectroscopies…”

“…The 13 C-NMR spectra of complexes 1-2 showed that the d(COO) signals shifted to the downfield region compared to that of the acid, HL indicating the carboxylate anion were bonded to tin(IV) atoms. Complex 1 is derivative of organodistannoxane dimer types which exhibited two sets of signals corresponding to the butyl groups in the 13 C-NMR spectra. These two sets of signals were assigned to the butyl groups linked to the exo-and endocyclic tin(IV) atoms, respectively [47].…”

“…Tin is a non-transition and biocompatible metal [5][6][7] and its complexes have shown significant antibacterial properties [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22]. However, tin complexes have been rarely studied against cancer [12,[23][24][25][26][27][28].…”