Chemomimetic concept

In agreement with the chemomimetic concept as defined by Eschen-moser, the panel of enzymatic transformations for the biosynthesis of purines that we currently observe in the cell can be hypothesized to have evolved from primitive chemical processes [48-50]. 2-Carbonitrile and 2-carboxamide AICA and AICN derivatives, respectively, were also used as intermediates for the synthesis of adenine 1 and 8-substituted adenines 7 and 8 [51]. In principle, purine derivatives 7 and 8 may pair with pyrimidine bases by formation of Watson-Crick or Hoogsteen hydrogen bond interactions. 

Treatment of HCN-polymer with 6.0NHC1 afforded adenine 1, AICN, 3,4-dihydroxypyrimidine 9 and 5-hydroxyuracil 10, while 1, AICN and orotic acid 11 were recovered after reaction with sodium hydroxide (Scheme 5). A reaction mechanism involving the formation of different aminopyridines as intermediates and reduction steps was proposed to explain the distribution of the obtained products. In accordance with the chemomimetic concept, orotic acid is a key intermediate in the current biosynthesis of pyrimidine nucleotides [62],... 

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See also in sourсe #XX -- [ ]

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