Synthesis and Characterization of Platinum (IV) complexes with S-alkyl Derivatives of Thiosalicylic Acid and the Crystal Structure of the S-butyl Derivative of Thiosalicylic Acid

New platinum(IV)-complexes with S-alkyl derivatives of thiosalicylic acid (alkyl = benzyl-(L1), methyl-(L2), ethyl-(L3), propyl-(L4), butyl-(L5)) have been synthesized and characterized by microanalysis, infrared spectroscopy, and 1H and 13C NMR spectroscopy. Th e bidentate S,O ligand precursor, the S-butyl derivative of thiosalicylic acid (S-bu-thiosal), was prepared, and its crystal structure was determined. Single crystals suitable for X-ray measurements were obtained by slow crystallization from a DMSO-water system. S-bu-thiosal crystallized in a P21/c space group of a monoclinic crystal system with a = 8.0732 (3) Å, b = 19.6769 (4) Å, c = 8.2291 (3) Å and Z = 4. S-bu-thiosal also has a coplanar geometry

Synthesis, Characterization, and Cytotoxicity of Binuclear Cooper(II)-Complexes with some S-Alkenyl Derivatives of Thiosalicyclic Acid

New complexes of copper(II) with S-alkenyl derivatives of thiosalicylic acid (alkenyl = propenyl-(L1), isobutenyl-(L2)) have been synthesized and characterized by microanalysis, infrared spectra, magnetic measurements, and by NMR spectra. The cytotoxic activity of two newly synthesized precursor S-alkenyl derivatives of thiosalicylic acid were tested using an MTT colorimetric technique on HCT-116 human colon carcinoma cells. The cytotoxic effect of the copper(II)- complexes were higher compared to the cytotoxicity of the corresponding ligand (for concentrations from 31.25 to 250 μM). Copper(II)-complexes showed a slightly lower cytotoxicity compared to cisplatin. Complexes of copper(II) with S-alkenyl derivatives of thiosalicylic acid (at concentrations from 250 to 1000 μM) had a cytotoxic effect on HCT-116 cells compared to cisplatin

DNA binding, antibacterial and antifungal activities of copper(II) complexes with some S-alkenyl derivatives of thiosalicylic acid

The biological activities of two binuclear copper(II) complexes containing S-alkenyl derivatives of thiosalicylic acid are reported [alkenyl = propenyl (L1), isobutenyl (L2)]. The structure of the complex with the S-isobutenyl derivative (C2) was confirmed by single-crystal X-ray structure analysis, which revealed that the structure consists of centrosymmetric, dinuclear complex molecules [Cu-2(S-i-butenyl-thiosal)(4)(DMSO)(2)] containing two Cu(II) centers bridged by four S-isobutyl-thiosalicylate ligands in a paddle-wheel type structure. The Cu(II) atom is situated in a distorted square-pyramidal environment formed by carboxylate oxygen atoms in the basal plane and a DMSO ligand in the axial position. The reactivities of the complexes toward guanosine-5-monophosphate (5-GMP) were investigated. Complex C2 ([Cu-2(S-i-butenyl-thiosal)(4)(H2O)(2)]) reacted more rapidly with 5-GMP than complex C1. The interactions of complexes C1 and C2 with calf thymus DNA (CT-DNA) were examined by absorption (UV-Vis) and emission spectral studies (ethidium bromide displacement studies), revealing good DNA interaction abilities. The antimicrobial activities of the free ligands and their complexes were tested by microdilution method, and both minimal inhibitory and microbicidal concentrations were determined. All the tested substances demonstrated selective and moderate antibacterial activity on gram-positive bacteria, but low antibacterial activity on gram-negative bacteria. Also, the tested substances demonstrated low antifungal activity

Antibacterial, antibiofilm and antioxidant screening of copper(II)-complexes with some S-alkyl derivatives of thiosalicylic acid. Crystal structure of the binuclear copper(II)-complex with S-propyl derivative of thiosalicylic acid

The spectroscopically predicted structure of the obtained copper(II)-complex with S-propyl derivative of thiosalicylic acid was confirmed by X-ray structural study. The binuclear copper(II)-complex with S-propyl derivative of thiosalicylic acid crystallized in two polymorphic forms with main structural difference in the orientation of phenyl rings relative to corresponding carboxylate groups. The antibacterial activity was tested determining the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) by using microdilution method. The influence on bacterial biofilm formation was determined by tissue culture plate method. In general, the copper(II)-complexes manifested a selective and moderate activity. The most sensitive bacteria to the effects of Cu(II)-complexes was a clinical isolate of Pseudomonas aeruginosa. For this bacteria MIC and biofilm inhibitory concentration (BIC) values for all tested complexes were in the range or better than the positive control, doxycycline. Also, for the established biofilm of clinical isolate Staphylococcus aureus, BIC values for the copper(II)-complex with S-ethyl derivative of thiosalicylic acid, [Cu-2(S-et-thiosal)(4)(H2O)(2)] (C3) and copper(II)-complex with S-butyl derivative of thiosalicylic acid, [Cu-2(S-bu-thiosal)(4)(H2O)(2)] (C5) were in range or better than the positive control. All the complexes acted better against Gram-positive bacteria (Staphylococcus aureus and Staphylococcus aureus ATCC 25923) than Gram-negative bacteria (Proteus mirabilis ATCC 12453, Pseudomonas aeruginosa, and P. aeruginosa. ATCC 27855). The complexes showed weak antioxidative properties tested by two methods (1,1-diphenyl-2-picrylhydrazyl (DPPH) and reducing power assay). (C) 2016 Elsevier B.V. All rights reserved