North Eastern Hill University

About: North Eastern Hill University is a education organization based out in Shillong, Meghalaya, India. It is known for research contribution in the topics: Population & Catalysis. The organization has 2318 authors who have published 4476 publications receiving 48894 citations.

Metal-Free Greener Syntheses of Pyrimidine Derivatives Using a Highly Efficient and Reusable Graphite Oxide Carbocatalyst under Solvent-Free Reaction Conditions

Abstract: Graphite oxide, a green metal-free carbocatalyst, has been successfully exploited for the library synthesis of biologically active pyrimidine derivatives. Reaction was carried out under solvent-free reaction conditions (SFRC) thereby reducing the application of hazardous chemicals and solvents. The present catalytic system eliminates the risk of metal contamination in the product which is viable for pharmaceutical industries and showed better catalytic activity under sustainable conditions compared to other classical catalytic systems. The catalyst, being heterogeneous in nature, can be easily recycled and reused up to nine consecutive runs without much decrease in catalytic activities thereby increasing sustainability of the procedure. Diversity in the formation of pyrimidine moieties has been exhibited with the tolerance of a large number of functional groups establishing the generality of this reaction. A few other cutting edge advantages of the present one-pot multicomponent methodology are high atom ...

Comprehensive analysis of the catalytic and structural properties of a mu-class glutathione s-transferase from Fasciola gigantica

Abstract: Glutathione S‒transferases (GSTs) play an important role in the detoxification of xenobiotics. They catalyze the nucleophilic addition of glutathione (GSH) to nonpolar compounds, rendering the products water-soluble. In the present study, we investigated the catalytic and structural properties of a mu-class GST from Fasciola gigantica (FgGST1). The purified recombinant FgGST1 formed a homodimer composed of 25 kDa subunit. Kinetic analysis revealed that FgGST1 displays broad substrate specificity and shows high GSH conjugation activity toward 1-chloro-2,4-dinitrobenzene, 4-nitroquinoline-1-oxide, and trans-4-phenyl-3-butene-2-one and peroxidase activity towards trans-2-nonenal and hexa-2,4-dienal. The FgGST1 was highly sensitive to inhibition by cibacron blue. The cofactor (GSH) and inhibitor (cibacron blue) were docked, and binding sites were identified. The molecular dynamics studies and principal component analysis indicated the stability of the systems and the collective motions, respectively. Unfolding studies suggest that FgGST1 is a highly cooperative molecule because, during GdnHCl-induced denaturation, a simultaneous unfolding of the protein without stabilization of any partially folded intermediate is observed. The protein is stabilized with a conformational free energy of about 10 ± 0.3 kcal mol−1. Additionally, the presence of conserved Pro-53 and structural motifs such as N-capping box and hydrophobic staple, further aided in the stability and proper folding of FgGST1.

Conductometric Studies on Micellization of Cationic Surfactants in the Presence of Glycine

Abstract: Values of the critical micelle concentration (cmc) and degree of counterion dissociation (α) of four cationic surfactants: cetyltrimethylammonium bromide (CTAB), cetylpyridinium bromide (CPB), cetylpyridinium chloride (CPC) and benzyldimethylhexadecylammonium chloride (BDHAC) in aqueous–glycine medium (concentration of glycine (Gly) varied from 0 to 0.20 mol·dm−3) were determined through conductometric measurements at 303 K. The effect of temperature on the micellization in the presence of 0.10 mol·dm−3 Gly were studied for the surfactants CTAB, CPC and BDHAC. With respect to the concentration of Gly, a decrease in the cmc was observed for CTAB, CPC and CPB whereas an increase was observed for BDHAC. A regular increase in α was obtained for CPB, CPC and BDHAC with respect to the concentration of Gly whereas values were roughly constant in the case of CTAB. Thermodynamic parameters were computed from the temperature dependence of the cmc values and it was found that the micellization process is exothermic. Compensation of enthalpy and entropy was observed for the micellization of CTAB, CPC and BDHAC in the presence of 0.10 mol·dm−3 Gly.