Molecular organization in liquid crystals: A comparative computational analysis

A comparative computational analysis of molecular organization in four-nematogenic acids (nOCAC) having two, four, six, and eight carbon atoms in the alkyl chain is carried out with respect to translatory and orientational motions. The evaluation of the atomic charge and dipole moment at each atomic center is performed through the complete neglect differential overlap (CNDO/2) method. The Rayleigh-Schrödinger perturbation theory, along with the multicentered-multipole expansion method, is employed to evaluate the long-range interactions, while the “6-exp” potential function is assumed for short-range interactions. The total interaction-energy values obtained through these computations are used to calculate the probability of each configuration at the phase transition temperature via the Maxwell-Boltzmann formula. Further, the flexibility of various configurations is studied in terms of variation of probability due to small departures from the most probable configuration. A comparative picture of molecular parameters, such as the total energy, binding energy, and total dipole moment, is given. An attempt is made to explain the nematogenic behavior of these liquid crystals in terms of their relative order and, thereby, to develop a molecular model for the liquid crystallinity.     

ChemInform Abstract: Towards Detection of a Long‐Lived Protonated Metal Cation: Generation of GeH2+ Using High‐Energy Collisions.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

A pharmacokinetic study to correlate the hypoglycemic effect of phlorizin in rats: Identification of metabolites as inhibitors of sodium/glucose cotransporters

Phlorizin (PRZ) is a natural product that belongs to a class of dihydrochalcones. The unique pharmacological property of PRZ is to block glucose absorption or reabsorption through specific and competitive inhibitors of the sodium/glucose cotransporters (SGLTs) in the intestine (SGLT1) and kidney (SGLT2). This results in glycosuria by inhibiting renal reabsorption of glucose and can be used as an adjuvant treatment for type 2 diabetes. The pharmacokinetic profile, metabolites of the PRZ, and efficacy of metabolites towards SGLTs are unknown. Therefore, the present study on the characterization of hitherto unknown in vivo metabolites of PRZ and pharmacokinetic profiling using liquid chromatography-electrospray ionization tandem mass spectrometry (LC/ESI/MS/MS) and accurate mass measurements is undertaken. Plasma, urine, and feces samples were collected after oral administration of PRZ to Sprague–Dawley rats to identify in vivo metabolites. Furthermore, in silico efficacy of the identified metabolites was evaluated by docking study. PRZ at an intraperitoneal dose of 400 mg/kg showed maximum concentration in the blood to 439.32 ± 8.84 ng/mL at 1 h, while phloretin showed 14.38 ± 0.33 ng/mL at 6 h. The pharmacokinetic profile of PRZ showed that the maximum concentration lies between 1 and 2 h after dosing. Decreased blood glucose levels and maximum excretion of glucose in the urine were observed when the PRZ and metabolites were observed in plasma. The identification and characterization of PRZ metabolites by LC/ESI/MS/MS further revealed that the phase I metabolites of PRZ are hydroxy (mono-, di-, and tri-) and reduction. Phase II metabolites are O-methylated, O-acetylated, O-sulfated, and glucuronide metabolites of PRZ. Further docking study revealed that the metabolites diglucuronide metabolite of mono-hydroxylated PRZ and mono-glucuronidation of PRZ could be considered novel inhibitors of SGLT1 and SGLT2, respectively, which show better binding affinities than their parent compound PRZ and the known inhibitors.     

ChemInform Abstract: Ab initio MO Study of Diverse Si3H3+ Isomers.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.