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221.
Konwarh R Gogoi B Philip R Laskar MA Karak N 《Colloids and surfaces. B, Biointerfaces》2011,84(2):1245-345
In the pursuit of making the nanoscale-research greener, the utilization of the reductive potency of a common byproduct of food processing industry i.e. orange peel is reported here to prepare biopolymer-templated "green" silver nanoparticles. Aqueous extract of orange peel at basic pH was exploited to prepare starch supported nanoparticles under ambient conditions. The compositional abundance of pectins, flavonoids, ascorbic acid, sugars, carotenoids and myriad other flavones may be envisaged for the effective reductive potential of orange peel to generate silver nanoparticles. The nanoparticles were distributed within a narrow size spectrum of (3-12 nm) with characteristic Bragg's reflection planes of fcc structure, and surface plasmon resonance peak at 404 nm. Anti-lipid peroxidation assay using goat liver homogenate and DPPH scavenging test established the anti-oxidant potency of the silver nanoparticles. Their synergy with rifampicin against Bacillus subtilis MTCC 736 and cytocompatibility with the human leukemic monocytic cell line, THP-1 were also investigated. Thus, the present work deals with the preparation of starch assisted anti-microbial, cytocompatible and free radical scavenging "green" silver nanoparticles. 相似文献
222.
Triple monoamine reuptake inhibitors have been implicated in the development of a new generation of antidepressants with higher efficacy than the currently existing therapies. In this paper, we have developed an alternative efficient synthetic route for triple monoamine reuptake inhibitor D-142 in 18.5% overall yield in 11 steps starting from diphenylmethane. D-142 was developed by us recently. The key step of the present synthetic strategy is the preferential formation of a bromohydrin from olefin via a cis-bromoinum intermediate, which introduced significant efficiency in the overall synthesis. Furthermore, we have developed an efficient way to recycle the optically active intermediate diol back to the desired chiral epoxide. 相似文献
223.
Chayanika Kashyap Siddhartha K. Purkayastha Shahnaz S. Rohman Dr. Ankur K. Guha 《Chemphyschem》2023,24(5):e202200504
The scope of Bergman cyclization is expanded computationally by exploring the cyclization in inorganic B, N substituted derivative. This substitution has introduced polarity into the transition state, which resulted in dramatic lowering of the activation barrier. Natural charge distribution throughout the reaction profile has ascertained this hypothesis. Single B and N atom substitution at 1 and 6 terminal positions lowers the activation barrier by almost half of the original value which becomes even lower in the complete B, N analogue. The parent Bergman and single B, N substituted products were characterized by significant biradical character while the complete B, N substituted analogue was characterized by significant zwitterionic character. Reduction in electron delocalization is also observed in the complete B, N substituted analogue. 相似文献
224.
Namrata Gohain Abhik Bordoloi Amlan J. Kalita Dr. Ankur K. Guha 《Chemphyschem》2023,24(18):e202300581
We report a global planar star-like cluster B3Li3 featuring three planar tetracoordinate boron centres with a rare spin avoided σ-σ diradical character. The cluster was found to be stable towards dissociation into different fragments. The spin density was found to be localized solely on the three boron atoms in the molecular plane. This spin avoided σ-σ diradical character leads to the extension of the coordination number to yield a neutral B3Li3H3 and a cationic B3Li3H3+ cluster with three planar pentacoordinate boron centres in their global minimum structures. The planar geometry of the aninonic B3Li3H3− cluster is slightly higher in energy. The planar global clusters were found to maintain planarity in their ligand protected benzene bound complexes, B3Li3(Bz)3, B3Li3H3(Bz)3 and B3Li3H3(Bz)3+ with high ligand dissociation energies offering candidature for experimental detection. 相似文献