Organic crystals absorb hydrogen gas under mild conditions

We have studied the hydrogen sorption on three well-known organic hosts that possess vacant lattice voids large enough to accommodate H2 molecules.     

Non-stoichiometry induced by differential oxygen/lone pair occupation in chiral bicyclic 1,1'-binaphthoxy cyclodiphosphazanes

Non-stoichiometry and isostructurality in a set of chiral phosphorus compounds as a result of lone pair/oxygen exchange, substantiated by the combined use of 31P NMR spectroscopy and X-ray crystallography, is described.     

Low temperature magnetic properties of Cr0.25Co0.25Zn0.5Fe2O4 nano particles

Low temperature Mössbauer and AC susceptibility have been used to study relaxation phenomena in nano-sized particles of Cr_0.25Co_0.25Zn_0.5Fe₂O₄. From these studies, the energy density constant for this system has been estimated to be 4 x 10⁶ erg/cm³. Cation distribution has also been determined and the observed results are correlated to calculated relaxation times.     

Oxidative cyclization of thiophenolic and phenolic Schiff's bases promoted by PCC: a new oxidant for 2-substituted benzothiazoles and benzoxazoles

Pyridinium chlorochromate (PCC) supported on silica gel effects the oxidative cyclization of structurally diverse thiophenolic and phenolic Schiff's bases, thereby providing an efficient and convenient method for the synthesis of a library of 2-arylbenzothiazoles and 2-arylbenzoxazoles.     

Development and Validation of a Stability-Indicating LC Method for Determination of Bexarotene in Softgel Dosage Formulation

This study focuses on a novel liquid chromatographic approach that has been developed and approved for the quantitative determination of bexarotene (BXT), its potential impurities in drug substances and drug products. Chromatographic separation was developed on a Symmetry C₈ (150 × 4.6) mm 5-µm column with a mobile phase containing an isocratic mixture of acetonitrile:DI water:glacial acetic acid (650:350:7.5) v/v/v at a flow rate of 1.2 mL min^?1, and quantitation was carried out using ultraviolet detection at 262 nm for BXT and 290 nm for BHA with a column temperature of 35 °C. The resolution among butylated hydroxyanisole (BHA), BXT and its process-related impurity-A was found to be greater than 5. Regression analysis confers an R value (correlation coefficient) higher than 0.998 for BHA, BXT and impurity-A. The detection level for BXT impurities was found at a level below 0.03% (0.18 µg mL^?1). The inter- and intra-day precisions for BHA, BXT and impurities were evaluated and found to have a %RSD of less than 3.0.     

Population Genetic Structure and Marker Trait Associations Using Morphological,Phytochemical and Molecular Parameters in <Emphasis Type="Italic">Habenaria edgeworthii</Emphasis>—a Threatened Medicinal Orchid of West Himalaya,India

Habenaria edgeworthii Hook. f. ex Collett is an important terrestrial orchid used in different Ayurvedic formulations. In the present study, variations among morphological, phytochemical and molecular markers were assessed. A significant difference was observed among populations using morphological traits. Inter-simple sequence repeat (ISSR) data revealed lower genetic diversity at population level (He = 0.207) as compared to species level (He = 0.334). Analysis of molecular variance (AMOVA) indicates 74 % variation among populations and 26 % within population. Tuber extracts showed significantly (p < 0.05) higher total phenolics and flavonoids among the populations. Antioxidant activity determined by 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and ferric reducing antioxidant power (FRAP) assays exhibited considerable antioxidant potential. Furthermore, the associations between molecular and morphological and phytochemical attributes were studied using multiple regression analysis (MRA). Several ISSR fragments were associated with some morphological and phytochemical traits. These ISSR fragments can be useful for breeding programme of the species when no other genetic information, such as linkage maps and quantitative trait loci, is available.