The mode of coordination of8 manganese(fI), cobaltm, nickel(H), copper(II), zinc(H), lead(II) and cadmium(I1) to sodium ascorbate (NaHAsc) was investigated using IR, UV-visible, AAS, elemental microanalyzer, conductivity, magnetic and 'M and I3C NMR spectroscopic studies, NaNAsc is bidentate and coordination was through the carbonyl group and the oxygen atom of carbon-2 enolic hydfoxyl grou...

The mol-ecular conformation of the title compound, C(18)H(18)O(5), is stabilized by a strong intra-molecular hydrogen bond between the hydroxyl and carbonyl groups. The C=C double bond displays an E configuration while the carbonyl group shows an S-cis configuration relative to the double bond. The dihedral angle between the two rings is 15.0 (1)°.

The crystal structure and the dynamic feature of molecular structure in solution for 1,8-dibenzoyl-2,7-dimethoxynaphthalene are revealed by X-ray crystallographic analysis and VT-NMR measurements. In crystal, the molecule of the title compound is located on a twofold rotation axis. The two benzoyl groups are situated in an opposite direction. The dihedral angle between the mean planes of the ph...

The mechanism of Michael addition of malononitrile to chalcones catalyzed by Cinchona alkaloid aluminium(III) complex has been investigated by DFT and ONIOM methods. Calculations indicate that the reaction proceeds through a dual activation mechanism, in which Al(III) acts as a Lewis acid to activate the electrophile α,β-unsaturated carbonyl substrate while the tertiary amine in the Cinchona al...

Diketoreductase catalyzes a two-step bioreduction on a dicarbonyl substrate through a novel dual catalysis mode, in which random hydride attack simultaneously forms two mono-carbonyl intermediates, and subsequently distinct catalytic sites are responsible for the reductions of respective carbonyl group of the intermediates to yield the final dihydroxy product.

Excess production of nitric oxide by activated macrophages via inducible nitric oxide synthase leads to the development of various inflammatory diseases. Heme oxygenase-1 expression via activation of nuclear factor-erythroid 2-related factor 2 inhibits nitric oxide production and inducible nitric oxide synthase expression in activated macrophages. Okanin is one of the most abundant chalcones fo...

Friedel-Crafts acylation of the aryldiazirine with ω-ester-α-acyl halide and successive reduction of the carbonyl group to methylene with triethylsilane and trifluoroacetic acid gave diazirinylated fatty acids. Photoaffinity labeling with the carbene generating precursor, 3-phenyl-3-trifluoromethyldiazirine, has become increasingly important as a photophor. However, the complicated synthesis of...

The natural abundant two-dimensional exchange CNMR revealed the very close proximity between the carboxyl carbon of PMAA and carbonyl carbon of PVAc in the miscible PMAA/PVAc = 3/1 blend. The estimated distance between the CO carbons is approximately 0.37 nm. This close distance is induced by a strong hydrogen bond between the hydrogen of carboxyl group for PMAA and the oxygen of carbonyl group...

I.r. difference spectroscopy combined with 13C and 18O double-isotope substitution was used to examine the ester acyl carbonyl stretching vibration of hydrocinnamoyl-chymotrypsin. A single acyl carbonyl stretching band was observed at 1731 cm-1. This contrasts with previous i.r. and resonance Raman spectroscopic studies of a number of trans-3-arylacryloyl-chymotrypsins which showed two acyl car...

In the title compound, C(9)H(13)NO(2), there are two independent mol-ecules per asymmetric unit. The mol-ecules are very similar and almost planar, with the ethoxy-carbonyl group anti to the pyrrole N atom. The two independent mol-ecules are joined into dimeric units by strong hydrogen bonds between NH groups and carbonyl O atoms.