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Über Pterinchemie 51. Mitteilung [1] CNDO-Rechnungen an Pterin, 6,7-Dimethyl-7,8-dihydropterin und 5-Formyl-6, 7-dimethyl-5,6,7,8-tetrahydropterin

✍ Scribed by Jost H. Bieri; Rudolf E. Geiger

Publisher
John Wiley and Sons
Year
1975
Tongue
German
Weight
255 KB
Volume
58
Category
Article
ISSN
0018-019X

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✦ Synopsis

Abstract

The ^13^C‐NMR.‐spectra of 7,8‐dihydropterines and 5,6,7,8‐tetrahydropterines show a large difference in the chemical shifts of the 4a‐ and 8a‐sp^2^‐carbon atoms. From the CNDO calculations it is apparent that there is a considerable difference in electron density at C(4a) and C(8a) atoms, which leads to a strong polarity of the CC‐Bond. The electron distribution in the highest occupied molecular orbital (HOMO) is discussed.

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