Spectroscopic, SOD, anticancer, antimicrobial, molecular docking and DNA binding properties of bioactive VO(IV), Cu(II), Zn(II), Co(II), Mn(II) and Ni(II) complexes obtained from 3-(2-hydroxy-3-methoxybenzylidene)pentane-2,4-dione.

Novel macrocyclic Schiff base complexes [[ML]X; where M = Cu(II), Co(II), Ni(II), Zn(II), Mn(II) and VO(IV); L = macrocyclic ligand; X = Cl2 and SO42-] have been synthesized and characterized by microanalytical, 1H, 13C NMR, IR, Mass, UV-Vis, EPR spectral studies, as well as conductivity data. All the complexes exhibit square-planar geometry except vanadium complex. Magnetic susceptibility measurements and high conductance data reveal the monomeric and electrolytic nature of the complexes. Electronic absorption, cyclic voltammetry, viscosity measurements have been carried out on the interaction of the complexes with DNA. The results suggest that the complexes bind to DNA by intercalation via the aromatic ring of the macrocycle into the base pairs of DNA. Using gel electrophoresis experiment in the presence and absence of oxidant (H2O2) the nuclease cleavage activity of the complexes has been performed on plasmid DNA. The results demonstrate that most of the complexes have promising superoxide dismutase (SOD)-mimetic activity. The in vitro cytotoxicity of ligand and its complexes has also been evaluated against human breast and colon carcinoma cells. Binding interactions and energies of ligand and its metal complexes [ML]2+ (M = VO(IV), Mn(II), Co(II), Ni(II), Cu(II), Zn(II)) against the receptors EGFR and HER2 are performed using the Auto dock module. Consequently, it is found that the ligand is strong inhibitor for EGFR and HER2 while [VOL]SO4 is good inhibitor for EGFR and [ZnL]Cl2 is moderate inhibitor for HER2. The antimicrobial activity of the ligand and its complexes against bacteria Salmonella typhi, Staphylococcus aureus, Escherichia coli and Bacillus subtilis and fungi Aspergillus niger, Aspergillus flavus, Candida Albicans and Rhizoctonia bataicola. The complexes have higher activities than the macrocyclic free Schiff base. Communicated by Ramaswamy H. Sarma.

Synthesis and photophysical properties of pyridyl conjugated triazole appended naphthalenediimide derivatives.

A series of three substituted triazole appended NDI-derivatives, 2,7-bis(3,5-di(pyridin-X-yl)-4H-1,2,4-triazol-4-yl)benzo[lmn][3,8]phenanthroline-1,3,6,8(2H,7H)-tetraone (where X = 2, NDI-PyTz-1; 3, NDI-PyTz-2; and 4, NDI-PyTz-3), were designed, synthesized and well characterized using various analytical and spectroscopic techniques. All the three NDI-PyTz derivatives exhibit decent electronic properties as suggested by DFT, cyclic voltammetry and fluorescence studies. In particular, NDI-PyTz-1 demonstrated the generation of a stable anion radical [NDI-PyTz-1]˙-.

EGFR, HER2 target based molecular docking analysis, in vitro screening of 2, 4, 5-trisubstituted imidazole derivatives as potential anti-oxidant and cytotoxic agents.

In our endeavor towards the development of potent molecules for cancer diseases, we have designed and synthesized a series of 2,4,5-trisubstituted imidazole derivatives (B1-B24) and characterized by using various spectroscopic techniques. All these compounds are further evaluated for their in vitro anti-cancer, anti-oxidant activities and molecular docking studies against EGFR, HER2 protein receptors. The in vitro anti-cancer activity analysis reveals that compounds B11 and B16 were found to be effective scaffolds against the tested human cancer cell lines IMR-32, A549 and HeLa. Particularly, B16 and B11 showed effective cytotoxicity against A549 and IMR-32 with IC50 values of 09.521±0.54µM and 10.294±0.43µM, respectively. Moreover, compounds B17, B18 and B23 showed potent activity towards the anti-oxidant screening with IC50 values of 5.87±1.73µM, 6.29±1.27µM and 4.95±1.81µM, respectively compared to standard ascorbic acid. Molecular docking was performed against the EGFR, HER2 protein receptors to provide more insight into their mechanism of interaction by comparing with standard EGFR, HER2 inhibitors like Gefitinib (EFGR), Lapatanib (EGFR), Afitinib (HER2) and Canertinib (HER2). Compounds B15, B16, B11 and B10 were exhibiting their minimum binding energies. Out of the aforementioned docked molecules, B15 and B16 showed the best binding energies of -11.15kcalmol-1, -10.70kcalmol-1 and -10.49kcalmol-1, -10.12kcalmol-1 against EGFR and HER2 protein receptors, respectively. The molecular docking results are well corroborated with the in vitro anti-cancer activity finding.

Design, synthesis and biological evaluation of 8-substituted-6-hydrazonoindolo[2,1-b]quinazolin-12(6H)-one scaffolds as potential cytotoxic agents: IDO-1 targeting molecular docking studies.

Herein, we have reported the synthesis of 18 novel 8-substituted tryptanthrin analogues based on our earlier work. All these tryptanthrin analogues were well characterized by 1H &13C NMR, FT-IR, Mass Spectrometry and Elemental Analysis. All these 8-substituted analogues were screened for their anti-oxidant activity by DPPH radical scavenging assay. Out of all the tested compounds, T11, T12, T17 and T18 showed potent anti-oxidant activity. The anti-cancer activity have been performed by using MTT assay protocol and their results depicts that compounds having the 4-pyridyl or 4-carboxyphenyl substituents at the 8th position of the tryptanthrin framework are found to be the most promising cytotoxic agent against A549, MCF-7 and HeLa human cancer cell lines compared to others as well as with the standard drug cisplatin. Moreover, the comparative molecular docking studies against the three protein receptors IDO1, EGFR and HER2 strongly suggested that IDO1 is the best target protein, which exhibits lowest binding energies of -11.73 and -11.61kcalmol-1 for T11 and T12 scaffolds, respectively towards the in vitro anti-cancer activity.

Novel substituted hydrazono indolo[2,1-b]quinazoline-6,12-dione analogues as cytostatic agents: Synthesis, crystal structure, biological evaluation and molecular docking studies.

A series of novel substituted hydrazono indolo[2,1-b]quinazoline-6,12-dione analogues have been synthesized and screened for their in vitro cytotoxic and antimicrobial activities. Among all the target compounds, 3c exhibited the most potent inhibitory activity against three cancer cell lines MCF-7, A549, HeLa with IC50 values 07.14±1.285µM, 09.18±0.968µM and 10.57±0.581µM respectively, while maintaining low toxicity towards non-cancer originated cell line, HEK-293. The detailed studies about molecular interactions with probable target protein indoleamine 2,3-dioxygenase (IDO1) were done by using docking simulations. The results from docking models are in consistent with the experimental in vitro cytotoxic activity conclusions i.e. 3c shows the highest binding energy -11.25kcal/mol. Furthermore, antimicrobial studies revealed that the compound 3e has shown excellent anti bacterial activity against four tested strains and the compounds 3b, 3e and 3f have shown good anti fungal activity against two tested organisms as compared with their standard drugs.