Chirality is of primary importance in many areas of chemistry and has been extensively investigated since its discovery. We introduce here a description of central chirality for tetrahedral molecules using a geometrical approach based on complex numbers. According to this representation, for a molecule having n chiral centers it is possible to define an "index of chirality chi." Consequently, a...

A new spectroscopic method of triple resonance is proposed for studying chirality of a molecule of C₁ symmetry. Each enantiomer of such a molecule is of mixed parity and thus exhibits all three a-, b-, and c-types of rotational spectra. The present study concludes, by using time-dependent perturbation theory, that the transition probability between two of the three rotational levels under tripl...

The current situation of chiral drug development in Japan was investigated. The trend in the Japanese pharmaceutical development is increasingly moving towards the development of single isomers rather than racemates. The development of single-enantiomer drugs was made possible by the current technologies of asymmetric synthesis and chiral separation, and encouraged by the guidelines on the deve...

Methamphetamine was detected in a 77-year-old male who had a history of congestive heart failure. Using a modification of a previously reported method, trifluoroacetyl-l-prolyl chloride was used to derivatize sympathomimetic amines to allow separation and identification of individual enantiomers. The l-enantiomer of methamphetamine and a trace amount of l-amphetamine were found in blood and uri...

A chemically bonded cellulose tris(3,5-dimethylphenylcarbamate) chiral stationary phase (CSP) was prepared by a radical polymerization reaction. The prepared CSP was packed into fused-silica capillaries with inner diameter of 75 microm to perform enantiomer separations in CEC. The electrochromatographic behavior of the CSP was investigated. On the prepared CSP, high EOF could be generated under...

Microwave three-wave mixing allows for enantiomer-selective excitation of randomly oriented chiral molecules into rotational states with different energy. The random orientation is reflected in the degeneracy spectrum respect to orientational quantum number M and reduces, if not accounted for, enantiomer-selectivity. Here, we show how design pulse sequences maximal enantiomer-selectivity from a...