Aqueous reactions of HCN — amino acids and purines

Miller (1953) demonstrated that the most plausible mechanism for the production of amino acids in his experiment was a Strecker or cyanohydrin synthesis. In later work it has become clear that parallel reaction pathways are possible, an addition of HCN to an aldehyde to produce the hydroxy-nitrile  

An alternative route to certain of the amino acids as well as to the purines involves the oligomerization of HCN to produce the tetramer and further, as yet undefined oligomeric products  

The aqueous solution chemistry of HCN leading to the production of biologically interesting products has been studied by Sanchez et al. (1967). In dilute solutions, where the concentration of HCN is less than about O.OIM, the principle reaction is hydrolysis to formate and ammonia. Substantially 

Subsequently the purines can be synthesized by further reactions with HCN, cyanogen or cyanate. Alternatively, hydrolysis of the oligomer under mild conditions yields adenine as well as a number of other products (Ferris et al., 1977 and 1978 see Table III). The purines guanine, hypoxanthine and xanthine have also been tentatively identified (Ferris et al., 1978 Schwartz and Goverde, unpublished). It is significant that no additional ammonia need be added for this reaction sequence (ammonia is, however, produced during the oligomerization and the hydrolysis). 

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