Theoretical investigation on the binding specificity of fluorinated sialyldisaccharides Neu5Acα(2–3)Gal and Neu5Acα(2–6)Gal with influenza hemagglutinin H1 – A Molecular Dynamics Study

In the present study, the hydroxyl groups at the C4 and C7 positions of sialic acid and C6 position of galactose in Neu5Acα(2–3)Gal (N23G) and the hydroxyl groups at the C8 position of sialic acid and C3 and C4 positions of galactose in Neu5Acα(2–6)Gal (N26G) were substituted with fluorine atoms, respectively. Molecular dynamics simulations of 100 ns duration were carried out to investigate the structural and dynamical behavior of H1 bound with the tri-fluorinated N23G and N26G (FN23G and FN26G). Based on energy analysis, it was concluded that FN26G should be a better binder for hemagglutinin (H1) than FN23G and it might act as an inhibitor for influenza.     

Measurement of high-power microwave pulse under intense electromagnetic noise

KALI-1000 pulse power system has been used to generate single pulse nanosecond duration high-power microwaves (HPM) from a virtual cathode oscillator (VIRCATOR) device. HPM power measurements were carried out using a transmitting-receiving system in the presence of intense high frequency (a few MHz) electromagnetic noise. Initially, the diode detector output signal could not be recorded due to the high noise level persisting in the ambiance. It was found that the HPM pulse can be successfully detected using wide band antenna, RF cable and diode detector set-up in the presence of significant electromagnetic noise. Estimated microwave peak power was ∼59.8 dBm (∼1 kW) at 7 m distance from the VIRCATOR window. Peak amplitude of the HPM signal varies on shot-to-shot basis. Duration of the HPM pulse (FWHM) also varies from 52 ns to 94 ns for different shots.     

A novel series of anthraquinone-based discotic liquid crystals with bulky substituents: synthesis and characterization

A novel series of anthraquinone-based discotic liquid crystals with bulky substituents, namely 1,5-dibenzyloxy-2,3,6,7-tetraalkyloxy-9,10-anthraquinones, has been synthesized starting from gallic acid. This is, to our knowledge, the first example of bulky substitution in a discotic C₂-symmetric molecule forming columnar phases. Except for the lowest homologue, all members of this series are found to exhibit columnar mesophases; the low temperature mesophase appears to be three-dimensionally ordered whereas the high temperature mesophase is hexagonal columnar (Col_h). We find that the introduction of benzyl substituents for alkyl chains (in the 1,5-positions) on the anthraquinone hexaalkoxylates stabilizes the three-dimensionally ordered phase, whereas it destabilizes the Col_h phase, compared with the anthraquinone hexaalkoxylates. Interestingly, the three-dimensionally ordered phase extends down to -50 °C, making these new derivatives suitable for device applications.     

Comments on Some Recent Results on Controllability of Abstract Differential Problems

In this note we comment on some recent papers treating exact controllability of abstract control problems with a linear part dominated by a sectorial operator.     

Simple and efficient synthesis of 2,6-dialkyl-3,5-dialkoxycarbonyl-4-(3-aryl-1-phenyl-pyrazol-4-yl)pyridines using TPAP/NMO as a catalyst under mild conditions

Biologically important pyrazolylpyridines were synthesized in excellent yield by the oxidation of pyrazolyl 1,4-dihydropyridines (pyrazolyl 1,4-DHPs) using tetrapropylammonium perruthenate/N-methylmorpholine-N-oxide (TPAP/NMO) under mild conditions at 0 °C.     

A facile enantioselective synthesis of enantiomerically pure (R)-phenoxybenzamine hydrochloride using the hydrolytic kinetic resolution method

A practical and highly efficient enantioselective synthesis of (R)-phenoxybenzamine hydrochloride has been described for the first time using Jacobsen’s hydrolytic kinetic resolution of a terminal epoxide as a key step and source of chirality.     

Granisetron,an antiemetic drug,and its cobalt complex

The crystal structures of granisetron [systematic name: 1‐methyl‐N‐(9‐methyl‐9‐azabicyclo[3.3.1]nonan‐7‐yl)indazole‐3‐carboxamide], C₁₈H₂₄N₄O, (I), an antinauseant and antiemetic agent, and its Co^II complex, diaqua[1‐methyl‐N‐(9‐methyl‐9‐azoniabicyclo[3.3.1]nonan‐7‐yl)indazole‐3‐carboxamide]cobalt(II) tetrachloride dodecahydrate, [Co(C₁₈H₂₅N₄O)₂(H₂O)₂]Cl₄·12H₂O, (II), have been determined by X‐ray diffraction. The granisetron molecule is in an extended conformation in both structures. Twisting of the central carboxamide group facilitates the Co^II coordination in (II). The Co^II atom is located on an inversion centre. The azabicyclononane ring adopts a chair–boat conformation in both structures. The molecules in (I) are linked into centrosymmetric dimers and form tetracyclic rings through C—H...O hydrogen‐bonding interactions. The simultaneous presence of free chloride ions in conjunction with a number of hydration water molecules in (II) provides interesting hydrogen‐bond patterns. This study can aid in the investigation of the properties of metal complexes with active pharmaceuticals in which the drug molecules play the role of a ligand.     

Facile synthesis and antimicrobial activity of manganese oxide/bentonite nanocomposites

Research on Chemical Intermediates - Manganese-oxide-intercalated bentonite clay (Mn3O4/BC) nanocomposites were synthesized via a thermal decomposition method using different precursors. The...