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Updated: May 22, 2026

A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products
Published on: September 9, 2016
Structure of adenosine-5'-mononicotinate (AMN) trihydrate: an analog of NAD for testing intramolecular stacking
1Center for Crystallographic Research, Roswell Park Memorial Institute, Buffalo, NY 14203.
Abstract:
C16H16N6O5.3H2O, Mr = 426.4, monoclinic, P21, a = 9.535 (2), b = 13.932 (2), c = 7.138 (2) A, beta = 93.13 (2) degrees, V = 946.85 A3, Z = 2, Dx = 1.495 g cm-3, lambda (Cu K alpha) = 1.5418 A, mu = 9.93 cm-1, F(000) = 428, T = 294 K, R = 0.045 and wR = 0.059 for 1460 observed reflections [I greater than 3 sigma (I)]. The AMN molecules, unlike NAD or other model structures of NAD, are not charged and exhibit intra- as well as intermolecular stacking of pyridine ring over adenine ring. There is extensive hydrogen bonding in the crystal involving the pyridine and adenine rings and the three water molecules. Rather surprisingly, the ester carbonyl O atom is not involved in the hydrogen bonding.
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