Molecular conformation of 2′-deoxy-3′,5′-di- O -acetyl adenosine. Crystal structure and high resolution proton nuclear magnetic resonance investigations
1987; NRC Research Press; Volume: 65; Issue: 2 Linguagem: Inglês
10.1139/v87-055
ISSN1480-3291
AutoresLéo H. Koole, Henk M. Buck, J. A. Kanters, Arie Schouten,
Tópico(s)Enzyme Structure and Function
Resumo2′-Deoxy-3′,5′-di-O-acetyl adenosine crystallizes in the orthorhombic space group P2 1 2 1 2 1 , and the cell dimensions are a = 7.768(1) Å, b = 12.890(1) Å, c = 15.495(1) Å; Z = 4 molecules per cell. Least-squares refinement converged at R = 0.054 for 1752 observed reflections. The adenine bases are linked via N 6 —H … N 1 and N 6 —H … N 7 hydrogen bonds, in such a way that infinite one-dimensional chains are formed. Comments are made on the fact that this structure is entirely different from the parallel dimer that was found for 3′,5′-di-O-acetyl thymidine. Furthermore, the conformational preferences of the title compound in aqueous solution have been determined with 300- and 500-MHz 1 H nmr. It is found that the X-ray structure and the solution conformation are essentially similar, except for the C 4′ —C 5′ conformation, that is γ − in the solid state, and predominantly γ + in solution.
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