@article{43a24ddcf5504c1786784429fbb6405b,
title = "Hydrogen-deuterium exchange in hypoxanthines",
abstract = "The rate of hydrogen-deuterium exchange of the {"}aromatic{"} protons of hypoxanthine and some of its derivatives has been measured at various pH levels and a mechanism is suggested for these reactions.",
author = "F. Bergmann and D. Lichtenberg and Z. Neiman",
note = "Funding Information: Thus, it appears that the mechanism of deuteriation of hypoxanthines is complex and requires further studies. Figure 2 demonstrates that the activation energy for the exchange in compound (5) is independent of the pH. Or -3 I I 1 II 28 30 32 34 1 10L 2.FIGURE Arrhenius function for the deuteriation of 3-methyl-hypoxanthirze in neutvnl and anionic forms. Full circles : pH 13. Activation energy 28 kcal./mole; opeia circles : pH 7. Activation energy 25 kcal./mole. Thus, it may be assumed that, at Ieast in this case, the same mechanism prevails for deuteriation of the neutral and the negatively charged forms. We thank Mr. I. Ringel for the n.m.r. measurements, and Mr. R. Knafo for the drawings. This work was supported in part by a grant from the Centre National de la Recherche Scientifique, under the responsibility of Professor B. Pullman, Institut de Biologie Physico-Chimique, Paris. (Received, June 30€h,1969; Corn. 953.) 1 F. J. Bullock and 0. Jardetzky, J. Org. Chew, 1964, 29, 1988. 2 F. fkrgmann, D. Lichtenberg, and 2. Nciman, Proceedings of the Second Jerusalem Symposium on “Quantum Aspects of Hetero-cyclic Compounds in Chemistry and Biochemistry” 1969, Israel Academy of Science and Humanity, in the press. 3 P. I3eak and E. M. Monroe, J. Org. Chem., 1969,34, 589.",
year = "1969",
doi = "10.1039/C29690000992",
language = "אנגלית",
pages = "992--993",
journal = "Chemical Communications",
issn = "1359-7345",
publisher = "Royal Society of Chemistry",
number = "17",
}