ISSN:
1432-1432
Keywords:
Aminoacyl ester
;
Asymmetric synthesis
;
Prebiotic
;
Origin of optical activity
;
Oligonucleotide
;
Genetic code origin
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary The aminoacylation of diinosine monophosphate (IpI) was studied. When the acylating agent was the imidazolide of N-(tert-butoxycarbonyl)-Dl-alanine, a 40% enantiomeric excess of thel isomer was incorporated at the internal 2′ site and the positions of equilibrium for the 2′⇆3′ migration reaction differed for theD andl enantiomers. The reactivity of the nucleoside hydroxyl groups decreased in the order 2′(3′)〉internal 2′〉5′, and the extent of reaction was affected by the concentration of the imidazole buffer (pH 7.1). In contrast, reaction of IpI with the imidazolide of unprotectedDl-alanine led to an excess of theD isomer at the internal 2′ site, while reaction with the N-carboxy anhydride ofDl-alanine proceeded without detectable stereoselection. The relevance of these results to the evolution of optical activity and the origin of genetically directed protein synthesis is discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02257375
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