Asymmetric photoreaction of amino acid by using circularly polarized undulator and external magnetic field

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The helical undulator at the hiroshima synchrotron radiation center was clarified as quasi monochromatic and variable wavelength light source with more than 97 % of circular polarization, about 10^<14> pf photon flux, and therefore was demonstrated as the high performance light source for asymmetric photoreactions. From the region around a pulsar it was demonstrated that helical undulator radiations in the energy range from infrared to hard X-ray are emitted as electrons are accelerated and spiraled by the induced electrie field and strong magnetic field around the pulsar. To determine both the identity and D, L enantiomer composition of amino acids formed by photoreactions, a high performance liquid chromatograph was improved to achieve 10^<-14> mole sensitivity for identification arid 10^<-13> mole for enantiomeric compositionBy using ArF excimer laser or KrCI excimer lamp UV irradiation to aqueous solutions of organic molecules such as amines and amides were carried out. Two types of amino acid formation mechanisms were identified : direct mechanism to form free amino acids and indirect mechanism to farm amino acid precursor that yields amino acids after hydrolysis. Selectivities to form amino acids containing the dame number of carbon atom of the starting organic molecules were also identified. The ratio of the amino acid yield by the direct and that by the indirect mechanism and the propensity rule for the identity of amino acid was found to be sensitive to the presence of ammonia. High resolution massy analysis reveals inclusion of nitrogen heterocycles in amino acid precursbrs