National Chemical Laboratory

About: National Chemical Laboratory is a facility organization based out in Pune, Maharashtra, India. It is known for research contribution in the topics: Catalysis & Nanoparticle. The organization has 8891 authors who have published 14837 publications receiving 387600 citations.

Zeolite-based organic–inorganic hybrid catalysts for phosgene-free and solvent-free synthesis of cyclic carbonates and carbamates at mild conditions utilizing CO2

Abstract: As-synthesized zeolite-beta exhibits high catalytic activity for the synthesis of cyclic carbonates and alkyl and aryl carbamates by a phosgene-free route, utilizing the greenhouse effect gas CO 2 . The reaction occurs with high yields of the desired products at mild conditions and without using any solvent or cocatalyst. Cyclic carbonates are synthesized by cycloaddition reaction of CO 2 with oxiranes (epichlorohydrin, propene oxide, styrene oxide and n -butene oxide) at 393 K and 6.9 bar. Alkyl and aryl carbamates are synthesized by the reaction of the corresponding amines, CO 2 and n -butyl bromide at 353 K and 3.4 bar. The as-synthesized zeolite-beta containing the encapsulated quaternary ammonium ions is not only reusable in several recycling experiments, but also shows superior activity to that of the corresponding homogeneous, quaternary ammonium halide salt generally used in the commercial synthetic practice. The microporous silica (inorganic) acting in concert with the encapsulated organic component constitutes an efficient, recyclable catalyst for this reaction.

"Click chemistry" inspired synthesis of pseudo-oligosaccharides and amino acid glycoconjugates.

Abstract: Various pseudo-oligosacchardies and amino acid glycoconjugates were synthesized via an intermolecular 1,3-dipolar cycloaddition (“click”) reaction using easily accessible carbohydrate and amino acid derived azides and alkynes as building blocks. It is pertinent to mention that the conjugation reaction is highly regioselective and high yielding and can be carried out under mild reaction conditions.

Molecular marker analysis of kernel size and shape in bread wheat

Abstract: The economic value of wheat grain is determined by the kernel morphology which is an important parameter for manufacturing different food products requiring specific grain characteristics. Although kernel size and shape have emerged as important breeding objectives, not much information is available about the number or location of associated gene(s)/quantitative trait loci. In the present study, a recombinant inbred line population of 106 plants (F 7 ) was phenotyped for four traits, namely kernel length. width, weight and factor form density (FFD) and genotyped with different polymerase chain reaction-based markers. Transgressive segregants were observed for all the traits and genetic correlation studies showed positive correlations between the majority of the traits. The number of markers associated with each trait ranged from two to nine and the phenotypic contribution by an individual marker ranged from 3.3 to 16.6%. Many of the markers showed linkage to more than one trait. Strategies for improving the wheat grain quality traits and the utility of such markers in marker-assisted selection (MAS) efforts are discussed.

A Diagnostic Reaction of Desulphovibrio desulphuricans

Abstract: THE sulphate-reducing bacteria at present available in pure culture are Desulphovibrio desulphuricans, its aestuarii variant1, the thermophilic Clostridium nigrificans (earlier known as D. thermodesulphuricans 2) and the new species D. orientis 3. The species D. rubentschickii and its variant anomalous, able to utilize acetate and/or butyrate4, have so far defied re-isolation.