Review Chiral resolutions, asymmetric synthesis and amplification of enantiomeric excess

The origin and amplification of biomolecular chirality

“…Assuming that positrons retain their longitudinal polarization while slowing down to form Ps and looking for possible stereoselective effects, Garay et al (1973;1974a, b) studied the annihilation of positrons by the D-and L-isomers of tryptophan, phenytalanine, tyrosine and dihydroxyphenylalanine. These arguments were bolstered by the inability of several other investigators (Dezsi et al, 1974;Brandt and Chiba, 1976;Ache, 1977, 1979) who, again using ZZNa positron sources, were unable to find any significant differences whatsoever in the lifetimes or intensities of short-or long-lived components of the positron lifetime spectra observed between D-and L-enantiomers of a variety of organic compounds. Garay's results were immediately questioned by Rich (1976), who argued that the chirality of the positron would be lost during deceleration before Ps formation could occur, and that the reported results, if valid, must have another explanation.…”

Spontaneous appearance of chirally asymmetric steady states in a reaction model including Michaelis–Menten type catalytic reactions

“…In addition, with rare exceptions, organic compounds found in cells are chiral, and the concentration of one enantiomer is overwhelmingly dominant over the other. [1][2][3][4][5][6][7] Though the present homochirality in the natural compounds is attributed to the activities of living organisms, it has been widely accepted that the origin of molecular homochirality on Earth preceded the origin of life. 1,8,9 Until now, various abiotic mechanisms explaining the origin of homochirality on Earth have been proposed.…”

Abstracts of Issol 2005, the 14th International Conference on the Origin of Life, Held in Beijing, from June 19–24, 2005

“…This means chiral autocatalysis is required in the reaction network. On top of that, the autocatalysis must be nonlinear to be effective (de Min et al, 1988;Saito and Hyuga, 2004;. Such chiral autocatalysis can be embodied in real system either by a direct non-linear autocatalysis, or by an indirect network autocatalysis.…”