Gandhi Institute of Technology and Management

About: Gandhi Institute of Technology and Management is a education organization based out in Visakhapatnam, Andhra Pradesh, India. It is known for research contribution in the topics: Computer science & Heat transfer. The organization has 3392 authors who have published 4043 publications receiving 29139 citations. The organization is also known as: GITAM & GITAM College.

IR and ESR studies of CuO substituted for PbO in eutectic lead vanadate glass system

Abstract: IR and ESR studies of CuO substituted for PbO in eutectic lead vanadate glasses of compositions x(CuO)(50 − x)PbO:50V2O5 with x = 0–15 mol%, prepared by melt quenching technique have been presented. It has been shown from X-ray diffraction that these samples are of amorphous nature. According to differential thermal analysis (DTA) studies, up to 10 mol% CuO substitution, the eutectic composition is maintained and it deviates for x = 15 mol% substitution. The structure of these glasses, investigated by means of IR studies show the presence of (VO3)n single chains and VO5 trigonal bipyramids. IR studies indicate that CuO is replacing PbO in the glass system. ESR spectra of CuO substituted samples are characterized by broad peaks probably because of the formation of Cu2+–V4+ exchange pairs. For devitrified CuO substituted samples the ESR spectra show exchange broadened but distinct features corresponding to V4+ and Cu2+entities. The ESR spectral features corresponding to Cu2+ indicate a d 3 z 2 - r 2 ground state, which indicates that Cu2+ probably has a tetragonally compressed co-ordination in lead metavanadate.

Current understanding of synergistic interplay of chitosan nanoparticles and anticancer drugs: merits and challenges.

Abstract: Recent advances have been made in cancer chemotherapy through the development of conjugates for anticancer drugs. Many drugs have problems of poor stability, water insolubility, low selectivity, high toxicity, and side effects. Most of the chitosan nanoparticles showed to be good drug carriers because of their biocompatibility, biodegradability, and it can be readily modified. The anticancer drug with chitosan nanoparticles displays efficient anticancer effects with a decrease in the adverse effects of the original drug due to the predominant distribution into the tumor site and a gradual release of free drug from the conjugate which enhances drug solubility, stability, and efficiency. In this review, we discuss wider applications of numerous modified chitosan nanoparticles against different tumors and also focusing on the administration of anticancer drugs through various routes. We propose the interaction between nanosized drug carrier and tumor tissue to understand the synergistic interplay. Finally, we elaborate merits of drug delivery system at the tumor site, with emphasizing future challenges in cancer chemotherapy.

Highly active mesoionic chalcogenone zinc(ii) derivatives for C‒S cross-coupling reactions

Abstract: The first mesoionic heavier chalcogenones, L1–L3 [L1 = 1-(2-mesitylene)-3-methyl-4-phenyltriazolin-5-selone; L2 = 1-(2-mesitylene)-3-methyl-4-phenyltriazolin-5-thione; L3 = 1-(benzyl)-2-3(methyl)-4-phenyltriazolin-5-selone], were isolated and characterised. Density functional theory was used to obtain insights into the σ donor and π accepting nature of mesoionic chalcogenones. Using these new ligands, a series of the first zinc(II) mesoionic chalcogenone complexes were isolated. Three mono nuclear zinc(II) chalcogenone complexes, [(L1)Zn(Cl)2(HOMe)] (1), [(L2)Zn(Cl)2(HOMe)] (3) and [(L2)Zn(Br)2(HOMe)] (4), and two dinuclear zinc complexes, [(L1)Zn(Br)(μ2-Br)]2 (2) and [(L3)Zn(Br)(μ2-Br)]2 (5), containing mesoionic thione and selone ligands were synthesized and characterised. These new complexes 1–5 represent the first structurally characterized mesoionic chalcogenone supported metal derivatives. Furthermore, all zinc complexes were characterized by thermogravimetric analysis and UV-vis spectroscopy. The solid-state structures of all zinc complexes were determined by single-crystal X-ray diffraction. The catalytic activities of the zinc(II) complexes in thioetherification reactions were investigated without scrubbing of oxygen. The scope of the catalytic reactions was explored with a wide range of thiophenols and aryl halides. The diaryl thioethers were obtained in very good yield under mild conditions. The present protocol furnishes a synthetic route for the C–S cross-coupling of thiophenols and aryl halides without scrubbing oxygen and moisture.