Mapping the Landscape of Potentially Primordial Informational Oligomers: Oligodipeptides and Oligodipeptoids Tagged with Triazines as Recognition Elements

Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
Angewandte Chemie International Edition (Impact Factor: 11.26). 03/2007; 46(14):2470-7. DOI: 10.1002/anie.200603207
Source: PubMed


(Chemical Equation Presented) Pairing up: Oligodipeptide, oligodeoxy-dipeptide, or oligodipeptoid backbones tagged with the 2,4-diaminotriazine nucleus pair strongly with complementary DNA and RNA. This is in sharp contrast with the behavior of the 2,4-dioxotriazine nucleus, which does not act as a nucleo-base in these systems.

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    • "The same reaction performed at room temperature afforded glycine, parabanic acid, hydantoin and hydantoin derivatives as the only recovered products (spark discharge performed under an inert argon atmosphere only yielded triazines). Triazines are prebiotically relevant, since these compounds embedded in peptidic oligomers can establish strong interactions with nucleobases [82] [83]. The authors suggested a reaction pathway involving the formation of cyanoacetylene and cyanoacetaldehyde for the synthesis of cytosine and uracil, while triazines were most probably obtained by a sequence of urea transformations with biuret (aminocarbonyl urea) and isocyanic acid HCNO as key intermediates [84]. "
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