In the title compound, C(17)H(27)NO(4), which is an hydro-sinapic acid derivative with increased lipophilicity conferred by an additional alkyl chain, the central and the hexyl linear chains contain slightly shorter bond lengths [C-N = 1.316 (2) Å; average linear chain C-C = 1.487 (6) Å] than reported average values [Csp(2)-N = 1.334, C-C for CH(2)-CH(2) = 1.524 and 1.513 Å for CH(2)-CH(3)]. Th...

The folding of proteins is directed by a variety of interactions, including hydrogen bonding, electrostatics, van der Waals' interactions, and the hydrophobic effect. We have argued previously that an n→π* interaction between carbonyl groups be added to this list. In an n→π* interaction, the lone pair (n) of one carbonyl oxygen overlaps with the π* antibonding orbital of another carbonyl group....

Stereoelectronic effects modulate molecular reactivity and conformation. For example, the nucleophilic attack at a carbonyl carbon is preferred along the B€urgi Dunitz trajectory. This orientational preference stems from a stereoelectronic effect arising from the delocalization of an electron pair (n) of a nucleophile into an antibonding orbital (π*) of the carbonyl group. Our experimental and ...

Chlorophyll-a plays a fundamental role in the solar energy conversion processes that occur in oxygen evolving organisms, such as plants algae and cyanobacteria. To study the chlorophyll-a species at the heart of these solar conversion processes FTIR difference spectroscopy has been a valuable tool. However, FTIR difference spectra are only partially understood. To gain a more detailed understan...

Current limitations in protein structure prediction and design suggest an incomplete understanding of the forces governing protein folding. As such, noncovalent interactions in proteins, particularly hydrogen bonds, have received great attention [1,2]. In common secondary structure patterns like the α-helix and β-sheet, main-chain N–H hydrogen bond donors approach their carbonyl acceptors appro...

Methyl vinyl carbonyl oxide is an important intermediate in the reaction of isoprene and ozone and may be responsible for most of the (*)OH formed in isoprene ozonolysis. We use CBS-QB3 calculations and RRKM/master equation simulations to characterize all the pathways leading to the formation of this species, all the interconversions among its four possible conformers, and all of its irreversib...

In the title compound, C(19)H(14)ClNO(5), the aroyl group is attached to the naphthalene ring system with a non-coplanar configuration. The dihedral angle between naphthalene ring system and benzene ring is 70.62 (6)°. The nitro group is oriented in parallel with the adjacent carbonyl plane. The torsion angle of the carbonyl group and naphthalene ring is 54.68 (19)° (C-C-C-O), and that of nitro...

In the title compound, [Rh(C(13)H(16)NO)(C(18)H(15)P)(CO)]·0.5C(3)H(6)O, the Rh atom exhibits a square-planar coordination geometry, being coordinated by the N and O atoms of the bidentate β-diketonato ligand, a P atom from the triphenyl-phosphine unit and a C atom from the carbonyl group. The asymmetric unit also contains a disordered half-mol-ecule, lying about an inversion center, of the ace...

In the title compound, C17H22N2O4S, a thio-piperidine derivative, the piperidine ring has an envelope conformation with the methyl-ene C atom opposite to the C=S bond as the flap. The nitro-methyl substituent is equatorial while the eth-oxy-carbonyl group is axial. The mean planes of the nitro-methyl group, the carb-oxy group and phenyl ring are inclined to the mean plane through the five plana...