First stereoselective total synthesis of decytospolides A and B

The first synthesis of bioactive decytospolides A and B adopting an oxa-Michael addition as the key step is reported.     

Measuring powder flowability with a modified Warren Spring cohesion tester

The measurement of powder flowability is a major concern for most industrial processes that deal with the handling of bulk solids as raw materials,intermediates,or products.The development of devices that measure the flowability of non-aerated powders has not progressed as rapidly as might have been hoped since most research activities have been based on various types of shear testers intended to aid the design of hoppers.A new flowability indicator named as weighted cohesion (WS) is established using newly...     

Formulation and Optimization of Alkaline Extracted Ispaghula Husk Microscopic Reservoirs of Isoniazid by Box-Behnken Statistical Design

The main objective of the present work was to formulate and optimize a microparticulate sustained release drug delivery system of isoniazid by using a novel, alkaline extracted ispaghula husk as a polymer. Isoniazid microspheres of alkaline extracted ispaghula husk were prepared by emulsification internal ionic gelation method. Results of preliminary trials indicated that the polymer concentration, cross-linking agent and stirring speed had a noticeable effect on size and surface morphology. A four-factor three-level Box-Behnken design was employed to study the effect of independent variables on dependent variables. The particle size and entrapment efficiency varied from 30.75 to 61.78 µm and 62.27% to 85.80% respectively, depending on the polymer concentration, concentration of cross-linker and stirring speed. Optimized microspheres batch based on point prediction tool of design software exhibited 83.43% drug entrapment and 51.53 µm particle size with 97.80% and 96.37% validity, respectively at the following conditions: sodium alginate (3.55% w/v), alkaline extracted ispaghula husk (3.60% w/v), cross-linker concentration (7.82% w/v), and stirring speed (1200 rpm). The optimized formulation showed controlled drug release for more than 12 hours. The drug release followed Higuchi kinetics via a non-Fickian diffusion.     

Annelated Pyridines as Highly Nucleophilic and Lewis Basic Catalysts for Acylation Reactions

New heterocyclic derivatives of 9‐azajulolidine have been synthesized and characterized with respect to their nucleophilicity and Lewis basicity. The Lewis basicity of these bases as quantified through their theoretically calculated methyl‐cation affinities correlate well with the experimentally measured reaction rates for addition to benzhydryl cations. All newly synthesized pyridines show exceptional catalytic activities in benchmark acylation reactions, which correlate only poorly with Lewis basicity or nucleophilicity parameters. A combination of Lewis basicity with charge and geometric parameters in the framework of a three‐component quantitative structure–activity relationship (QSAR) model is, however, highly predictive.     

Micelles catalyzed one pot regio- and chemoselective synthesis of benzo[a]phenazines and naphtho[2,3-d]imidazoles ‘in H2O’

An efficient, novel, and concise one pot regio- and chemoselective synthesis of benzo[a]phenazines (4) and naphtho[2,3-d]imidazoles (8) has been accomplished in excellent yields by nucleophilic substitution reaction of 2,3-dichloro-1,4-naphthoquinone (1) with o-phenylenediamine (2) and benzamidines (7) respectively ‘in H₂O’ using base and micelles (SDS) as catalyst. Analog reaction of 2,3-dichloro-1,4-naphthoquinone (1) with 2-aminobenzenethiol (9) under identical conditions led to formation of a mixture of benzo[b]phenothiazine (10), benzo[a]phenothiazine (11), and benzo[a]-1,4-benzothiazino-3,2-phenothiazine (12) in 17%, 23%, and 57% yields, respectively.     

Total synthesis of two γ-butyrolactone containing compounds (Z,11S)-3,4-trans-11-hydroxy-3-methyldodec-cis-6-en-4-olide and (Z)-3,4-trans-11-oxo-3-methyldodec-cis-6-en-4-olide

The first total synthesis of (Z,11S)-3,4-trans-11-hydroxy-3-methyldodec-cis-6-en-4-olide and (Z)-3,4-trans-11-oxo-3-methyldodec-cis-6-en-4-olide was accomplished using Jacobsen hydrolytic kinetic resolution, Ohira–Bestmann reaction, regioselective alkyne addition to terminal carbon atom of epoxide, intramolecular TEMPO/BAIB mediated oxidative lactonization and partial hydrogenation as the key steps.     

Comprehensive quantum chemical calculations and molecular docking analysis of uracil mustard by first principle

Uracil mustard belongs to the nitrogen mustard family and is primarily used in anticancer drugs. The research that follows, investigates many quantum chemical features such as the computation of global minimum energies with no negative wavenumber values using the Density Functional Theory (DFT) with Becke three functional and 6-311G (d, p)/6–311++G (d, p) basis sets. All the vibrational modes have been calibrated and justified in comparison to their experimental counterparts. Mustard's polarizability and hyperpolarizability components, Natural Bond Analysis (NBO), electronic properties, Fukui function analysis, various global parameters, Quantum Theory of Atoms In Molecule (QTAIM) analysis, ADMET analysis, and docking analysis have all been investigated using the same theory and basis sets, indicating its biochemical significance. The biological activity of the molecule is reported by using PASS software. The Full fitness score and binding affinity parameters are utilized to determine the binding strength with 6cq3 protein. The acidity of the title molecule is calculated in water solvent by polarizable continuum model (PCM) solvent effects (estimated in water). The HOMO, LUMO, and MESP plots are used to explore the nature of binding and surfaces. The Fukui functions are computed using Mulliken atomic charges for neutral atoms, cations, and anions. The Ultraviolet–visible (UV–vis) of the molecule is computed employing the TD-DFT method.     

Effect of Temperature and Discharge Rate on Electrochemical Performance of Fiber Nickel–Cadmium Cell

Russian Journal of Electrochemistry - The effect of temperature and discharge rate on the discharge capacity of nickel–cadmium (Ni?Cd) cell is investigated quantitatively. Ni–Cd...     

In Vitro and In Silico Screening and Characterization of Antimicrobial Napin Bioactive Protein in Brassica juncea and Moringa oleifera

The study aimed to investigate the antibacterial activity of Mustard (Brassica juncea) and Moringa (Moringa oleifera) leaf extracts and coagulant protein for their potential application in water treatment. Bacterial cell aggregation and growth kinetics studies were employed for thirteen bacterial strains with different concentrations of leaf extracts and coagulant protein. Moringa oleifera leaf extract (MOS) and coagulant protein showed cell aggregation against ten bacterial strains, whereas leaf extract alone showed growth inhibition of five bacterial strains for up to 6 h and five bacterial strains for up to 3 h. Brassica juncea leaf extract (BJS) showed growth inhibition for up to 6 h, and three bacterial strains showed inhibition for up to 3 h. The highest inhibition concentration with 2.5 mg/mL was 19 mm, and furthermore, the minimum inhibitory concentration (MIC) (0.5 mg/mL) and MBC (1.5 mg/mL) were determined to have a higher antibacterial effect for <3 KDa peptides. Based on LCMS analysis, napin was identified in both MOS and BJS; furthermore, the mode of action of napin peptide was determined on lipoprotein X complex (LpxC) and four-chained structured binding protein of bacterial type II topoisomerase (4PLB). The docking analysis has exhibited moderate to potent inhibition with a range of dock score −912.9 Kcal/mol. Thus, it possesses antibacterial-coagulant potential bioactive peptides present in the Moringa oleifera purified protein (MOP) and Brassica juncea purified protein (BJP) that could act as an effective antimicrobial agent to replace currently available antibiotics. The result implies that MOP and Brassica juncea purified coagulant (BJP) proteins may perform a wide degree of antibacterial functions against different pathogens.