Off-shell aspects of the one-pion-exchange potential and their relationship to different forms of the nonstatic (subleading-order) chiral two-pion-exchange nucleon-nucleon potential are discussed. Various types of off-shell behavior are categorized and numerous examples are given. Recently derived potentials based on chiral approaches are supplemented by a rather general form of the two-pion-ex...

Carbon nanotubes are chiral molecular objects and therefore exist in two forms that are each other’s mirror image. Many aspects of these fascinating new materials have recently been explored but their chirality has hardly been addressed. We have investigated the charge transport through individual single-walled carbon nanotubes in the presence of a magnetic field parallel to the tube axis. For ...

A detailed investigation of the low-energy chiral expansion is presented within a model truncation of QCD. The truncation allows for a phenomenological description of the quark-quark interaction in a framework which maintains the global symmetries of QCD and permits a 1/Nc expansion. The model dependence of the chiral coefficients is tested for several forms of the quarkquark interaction by var...

Hexamethoxycalix[6]arene 3 forms a directional pseudorotaxane complex with the chiral axle (S)-(α-methyl-benzyl)benzylammonium 2+. Between two (endo-chiral)-2+@3 and (exo-chiral)-2+@3 stereoisomers, former is preferentially formed. This result confirms validity of “endo-α-methyl-benzyl rule”, previously reported by us. DFT calculations suggest that C-H···π interactions between methyl group 2+ c...

Modafinil [2-[(diphenylmethyl)sulfinyl]acetamide] is used clinically in the treatment of narcolepsy and sleeping disorders. The synthesis of modafinil, begins with the reaction of benzhydrol and thioglycolic acid in trifluoroacetic acid to afford benzhydrylsulfinyl acetic acid. The reaction of acid with thionyl chloride in benzene followed by treatment with ammonium hydroxide gave acetamide...

Controlling supramolecular self-assembly is a fundamental step towards molecular nanofabrication, which involves a formidable reverse engineering problem. It is known that a variety of structures are efficiently obtained by assembling appropriate organic molecules and transition metal atoms on well-defined substrates. Here we show that alkali atoms bring in new functionalities compared with tra...

Both anti (racemic mixture) and syn (meso) forms of a chiral, chelating chalcogen bond (ChB) donor interact with halides through short Se?X? directional interactions.

We present a general formulation of chiral gauge theories, which admits Dirac operators with more general spectra, reveals considerably more possibilities for the structure of the chiral projections, and nevertheless allows appropriate realizations. In our analyses we use two forms of the correlation functions which both also apply in the presence of zero modes and for any value of the index. T...

Copyright: © 2014 Maher HM. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Chiral molecules are constituents of a large proportion of therapeutic agents. Chiral compounds exist in two enantiomeric forms, whic...

Separation of the enantiomers of chiral drugs has become an important issue in analytical clinical chemistry in recent years, because of differences in the biological activity and pharmacokinetic properties of drug enantiomers [1,2]. Many drugs contain chirality centers; their enantiomers may have considerably different potency, type of pharmacological activity, pharmacokinetics, and metabolism...