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A new compound of the dithiocarbazate family, 2,2′-((disulfanediylbis((ethylthio)methylene))bis(hydrazin-2-yl-1-ylidene))bis(2-oxo-1,2-dihydro-3H-indol-3-ylidene), and its five metal complexes are synthesized. All compounds are characterized by elemental and mass analysis, spectroscopic (FT-IR, 1H-NMR and 13C-NMR) and TGA techniques. The crystal structure of the synthesized compounds is determined by single crystal X-ray diffraction analysis, which shows that the ligand acts as a tridentate chelate coordinated to Zn, Co and Ni ions in a distorted octahedral fashion and also as bidentate to Pt and Pd ions in a distorted square planar geometry. In order to investigate the compounds’ cytotoxicity, two human cancer cell lines of HeLa and MCF-7 are used and compared to the normal cell line of CHO. The clinical drug cisplatin is used as the standard drug. Fluorescence spectrophotometry is used to study the interaction of the compounds with human serum albumin (HSA) and parameters such as the Stern–Volmer quenching constant (KSV), the number of binding sites (n), association constants (Ka) and free energy changes (ΔG) at 298 K are calculated.

The syntheses of a new set of metal complexes MoO2L′(CH3OH), VOL′(CH3O)(CH3OH), , , SnL′Cl2 and SnL′I2 with a new ligand (L = (2,2′(disulfanediylbis((ethylthio)methylene)bis(hydrazin-2-yl-1-ylidene)bis(methanylylidene)) diphenol; L′ = S-ethyl-3-(2-hydroxyphenyl)methylenedithiocarbazate are described along with characterization by elemental analysis, mass spectrometry, spectroscopic (IR, 1H- and 13C-NMR) and TGA techniques. The crystal structures of compounds were determined by single crystal X-ray diffraction analysis and compared to powder X-ray diffraction (PXRD) patterns of the nano complexes obtained using ultrasonic methods. The PXRD results indicate that the compounds synthesized by ultrasonic methods have high crystallinity. The compounds were evaluated in an in vitro cytotoxicity study with two human cancer cell lines. The results of this study revealed that all complexes exhibit good cytotoxic activity when compared to the clinical drug, cisplatin. Interaction of the samples with human serum albumin (HSA) was investigated using fluorescence spectrophotometric methods and the Stern–Volmer quenching constant (KSV) and free energy changes (ΔG) were calculated at 298 K. The fluorescence quenching method is used to determine the number of binding sites (n) and association constants (Ka) at the same temperatures.

(bpy is 2,2'-bipyridine and Hex-dtc ishexyldithiocarbamato ligands) were synthesized and characterized by elemental analysis and spectroscopicstudies. The cytotoxicity assay of the complexes has been performed on chronic myelogenous leukemia cellline, K562, at micromolar concentration. Both complexes showed cytotoxic activity far better than that ofcisplatin under the same experimental conditions. The binding parameters of the complexes with calf thymusDNA (CT-DNA) was investigated using UV-visible and fluorescence techniques. They show the ability ofcooperatively intercalating in CT-DNA. Gel filtration studies demonstrated that platinum complex could cleavethe DNA. In the interaction studies between the Pd(II) and Pt(II) complexes with CT-DNA, several binding andthermodynamic parameters have been determined, which may provide deeper insights into the mechanism ofaction of these types of complexes with nucleic acids.Key Words : DNA binding and thermodynamic parameters, Anti-tumor activity, Pd(II) and Pt(II) complexesIntroductionDeoxyribonucleic acid (DNA) is the primary target mole-cule for most anticancer and antiviral therapies according tocell biology.

Two new palladium (II) complexes, [Pd (phen)(pip-dtc)] and [Pd(phen)(mor-dtc)], (where phen is 1,10-Phenantroline, pip-dtc is piperidinedithiocarbamate anion and mor-dtc is morpholinedithiocarbamate anion) have been synthesized and characterized by elemental analysis, spectroscopic studies (FT-IR, NMR, UV-Vis) and conductance measurement. In these complexes, the dithiocarbamate ligands coordinate with Pd (II) center as bidentate with two sulfur atoms. These two complexes have been tested against chronic myelogenous leukemia cell line, K562. They show values less than cisplatin and thus the mode of binding of the complexes to calf thymus DNA (CT-DNA) were investigated by ultraviolet difference and fluorescence spectroscopy. They can denature DNA, exhibit cooperative binding and intercalate into DNA. Several binding and thermodynamic parameters are also described.

There are very chemical reactions with very slow rates which can be catalyzed by enzymes. These biocatalysts need to moderate conditions for their catalytic activity and are stable in low temperature (between 15–50°C), average pH (5–10) and aqueous media. One of important things in enzymatic synthesis which has been recently noticed is the yield of reactions. Nowadays wide application of response surface methodology (RSM) was observed in organic chemistry. In one-variable-at-a-time technique only one parameter is changed and other parameters are kept at a constant level. It does not study the interactive effects among the variables, and does not illustrate the complete effects of the parameters on the process. Increasing the yield of product without increase in casts is carried out by modeling and optimization of reaction variables through statistical techniques such as RSM. In this paper, we reviewed some articles that used the RSM for optimization in the enzymatic synthesis.