A Stereospecific Synthesis of Pantothenic Acid Derivatives in Prebiotic Molecular Evolution on Earth
نویسنده
چکیده
A set of chemical reactions is proposed to account for the formation of pantothenic acid derivatives from a primeval atmosphere composed of ammonia, formaldehyde, propyne, ethyne, hydrogen sulfide, hydrogen and water. Three precursor molecules are initially formed; a di-adduct of propyne and the catalyst Mg.porphin, azetidine2one, and 2-amino ethyl mercaptan. These then react sequentially to form stereospecic pantothenic acid (+R). Most of the reactions appear to be exothermic except those requiring photochemical excitation. The reactions have been shown to be feasible from the overall enthalpy changes in the ZKE approximation at the HF and MP2 /6-31G* level. Key-Words: pantothenic acid, azetidine-2one, 2-amino ethyl mercaptan, porphin.
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