Conformation hydrogen bonding

A variety of hypothetical models have been proposed for the alamethicin pores. These generally invoke the bent helix monomer conformation, hydrogen bonding between adjacent helical monomers, and structural features compatible with the voltage dependence of the channels 201-204). Unfortunately experimental evidence is insufficient to distinguish between these models at present. 

Finally the effects of conformation, hydrogen bonding and Lewis acids on the intramolecular electron transfer, spectroscopy and photochemistry of amides were recently studied174-176 (equations 119-121). 

The NNRTIs are a class of compoimds that present a common butterflylike conformation. Parreira et al. [56] investigated the intramolecular factors that contribute to this conformation. Hydrogen bonds were analyzed by geometric and electrostatic criteria. Only the former allows the elucidation of the relative intensity of hydrogen bonds. The interaction between aromatic rings may contribute to the preferential conformation. Novel 1H,3H-... 

Fig. 6.15 Low energy conformation hydrogen bonding pairs of fluorescent monomer and substrate.74 Reproduced with permission...

Buemi, G., and Zuccarello, F., Molecular conformations, hydrogen bond strengths and electronic structure of usnic acid. An AMI and CNDO/S study, J. Mol. Struct. Theochem, 209, 89-99 (1990). 

Ramalingam, M., Venuvanalingam, P., Swaminathan, J., and Buemi, G., Ab initio and DFT studies on conformations, hydrogen bonding and electronic structures of glyoxal-monoxime and its methyl derivatives, J. Mol Struct. Theochem, 712, 175-185 (2004). 

Topological atoms have been used in the construction of the Quantum Isostere Database (QID) [19]. In QCT, the atomic properties are additive, which means that they can be combined to build functional groups or any meaningful fragment. It has been demonstrated that electronic and geometric properties of these atoms can be used to define intuitive descriptors such as shape, conformation, hydrogen bond... 

Unit cell composition atomic positions anisotropic displacement parameters bond lengths/angles disorder conformations hydrogen bonding crystal packing... 

Complexes axial base V k Conformation Hydrogen bond... 

Buemi G, Zuccarello F (1992) Molecular Conformations, Hydrogen-bond Strength s and Electronic Structure of Usnic Acid an AMI and CNDO/S Study. Theochem 68 89... 

In the all-ifwri conformation, hydrogen bonds form between amide hydrogen atoms and carbonyl oxygen atoms. 

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