ISSN:
0018-019X
Schlagwort(e):
Chemistry
;
Organic Chemistry
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
The synthesis of 8-azaguanine N9-, N8-, and N7-(2′-deoxyribonucleosides) 1-3, related to 2′-deoxyguanosine (4), is described. Glycosylation of the anion of 5-amino-7-methoxy-3H-1,2,3-triazolo[4,5-d]pyrimidine (5) with 2-deoxy-3,5-di-O-(4-toluoyl)-α-D-erythro-pentofuranosyl chloride (6) afforded the regioisomeric glycosylation products 7a/7b, 8a/8b, and 9 (Scheme 1) which were detoluoylated to give 10a, 10b, 11a, 11b, and 12a. The anomeric configuration as well as the position of glycosylation were determined by combination of UV, 13C-NMR, and 1H-NMR NOE-difference spectroscopy. The 2-amino-8-aza-2′-deoxyadenosine (13), obtained from 7a, was deaminated by adenosine deaminase to yield 8-aza-2′-deoxyguanosine (1), whereas the N7- and N8-regioisomers were no substrates of the enzyme. The N-glycosylic bond of compound 1 (0.1 N HCl) is ca. 10 times more stable than that of 2′-deoxyguanosine (4).
Zusätzliches Material:
1 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/hlca.19930760625
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