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.

Comparative genome analysis of mungbean (Vigna radiata L. Wilczek) and cowpea (V. unguiculata L. Walpers) using RFLP mapping data.

Abstract: Genome relationships between mungbean (Vigna tradiata) and cowpea (V. Unguiculata) based on the linkage arrangement of random genomic restriction fragment length polymorphism (RFLP) markers have been investigated. A common set of probes derived from cowpea, common bean (Phaseolus vulgaris), mungbean, and soybean (Glycine max) PstI genomic libraries were used to construct the genetic linkage maps. In both species, a single F2 population from a cross between an improved cultivar and a putative wild progenitor species was used to follow the segregation of the RFLP markers. Approximately 90% of the probes hybridized to both mungbean and cowpea DNA, indicating a high degree of similarity in the nucleotide sequences among these species. A higher level of polymorphism was detected in the mungbean population (75.7%) than in the cowpea population (41.2%). Loci exhibiting duplications, null phenotypes, and distorted segregation ratios were detected in both populations. Random genomic DNA RFLP loci account for about 89% of the currently mapped markers with a few cDNA and RAPD markers added. The current mungbean map is comprised of 171 loci/loci clusters distributed in 14 linkage groups spanning a total of 1570cM. On the other hand, 97 markers covered 684 cM and defined 10 linkage groups in the current cowpea map. The mungbean and cowpea genomes were compared on the basis of the copy number and linkage arrangement of 53 markers mapped in common between the two species. Results indicate that nucleotide sequences are conserved, but variation in copy number were detected and several rearrangements in linkage orders appeared to have occurred since the divergence of the two species. Entire linkage groups were not conserved, but several large linkage blocks were maintained in both genomes.

Room temperature ionic liquid promoted regioselective synthesis of 2-aryl benzimidazoles, benzoxazoles and benzthiazoles under ambient conditions

Abstract: A regioselective one-pot synthesis of 2-aryl benzimidazoles, benzoxazoles and benzthiazoles has been achieved in excellent isolated yields under ambient conditions using the ionic liquids, 1-butylimidazolium tetraflouroborate ([Hbim]BF4) and 1,3-di-n-butylimidazolium tetrafluoroborate ([bbim]BF4) as reaction media and promoters. There was no need for the use of an additional catalyst normally employed in the methodologies reported so far.

Acetalization of glycerol using mesoporous MoO3/SiO2 solid acid catalyst

Abstract: Acetalization of glycerol with various aldehydes has been carried out using mesoporous MoO3/SiO2 as a solid acid catalyst A series of MoO3/SiO2 catalysts with varying MoO3 loadings (1–20 mol%) were prepared by sol–gel technique using ethyl silicate-40 and ammonium heptamolybdate as silica and molybdenum source respectively The sol–gel derived samples were calcined at 500 °C and characterized using various physicochemical characterization techniques The XRD of the calcined samples showed the formation of amorphous phase up to 10 mol% MoO3 loading and at higher loading of crystalline α-MoO3 on amorphous silica support TEM analyses of the materials showed the uniform distribution of MoO3 nanoparticles on amorphous silica support Raman spectroscopy showed the formation of silicomolybdic acid at low Mo loading and a mixture of α-MoO3 and polymolybdate species at high Mo loadings Moreover the Raman spectra of intermediate loading samples also suggest the presence of β-MoO3 Acetalization of glycerol with benzaldehyde was carried out using series of MoO3/SiO2 catalysts with varying MoO3 loadings (1–20 mol%) Among the series, MoO3/SiO2 with 20 mol% MoO3 loadings was found to be the most active catalyst in acetalization under mild conditions Maximum conversion of benzaldehyde (72%) was obtained in 8 h at 100 °C with 60% selectivity for the six-membered acetal using 20% MoO3/SiO2 Interestingly with substituted benzaldehydes under same reaction conditions the conversion of aldehydes decreased with increase in selectivity for six-membered acetals These results indicate the potential of this catalyst for the acetalization of glycerol for an environmentally benign process