Synthesis 1989; 1989(12): 912-918
DOI: 10.1055/s-1989-27429
communication
© Georg Thieme Verlag, Rüdigerstr. 14, 70469 Stuttgart, Germany. All rights reserved. This journal, including all individual contributions and illustrations published therein, is legally protected by copyright for the duration of the copyright period. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher's consent, is illegal and liable to criminal prosecution. This applies in particular to photostat reproduction, copying, cyclostyling, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.

Stereoselective Glycosylation of Nitrobenzimidazole Anions: Synthesis of 1,3-Dideaza-2′-deoxyadenosine and Related 2′-Deoxyribofuranosides

F. Seela* , W. Bourgeois
  • *Laboratorium für Organische und Bioorganische Chemie, Fachbereich Biologie/Chemie, Universität Osnabrück, Barbarastr. 7, D-4500 Osnabrück, Federal Republic of Germany
Further Information

Publication History

Publication Date:
02 May 2002 (online)

The synthesis of 1,3-dideaza-2′-deoxyadenosine (1) and related benzimidazole 2′-deoxyribonucleosides is described. Solid-liquid phase-transfer glycosylation of 5(6)-nitrobenzimidazole (9) or 4(7)-nitrobenzimidazole (15) in acetonitrile with 1-chloro-2-deoxy-3,5-bis-O -(4-methylbenzoyl)-α-D-erythro-pentofuranose (10) gave regioisomeric N-1 and N-3 β-D-2′-deoxyribofuranosides. The glycosylation yield, as well as the ratio of anomers and regioisomers, was altered by use of either tris[2-(2-methoxyethoxy)ethyl]amine (TDA-1) or [18]crown-6 as phase-transfer catalysts and potassium hydroxide or potassium carbonate as inorganic bases, respectively. Zemplén-deprotection and subsequent catalytic hydrogenation afforded the corresponding amino compounds 1, 2, 4, 5 and 7. Structural proof of anomeric and regio-isomeric compounds was made on the basis of 1H- and 13C-NMR spectroscopy. The benzimidazole 2′-deoxyribofuranosides 4 and 5 exhibit strong fluorescence at λmax =362 and 395 nm, respectively. 1,3-Dideaza-2′-deoxyadenosine (c1c3Ad, 1) is more stable in 1 N hydrochloric acid than dA (3a). Under alkaline conditions, compound 1 decomposes whereas the regioisomer 2 is stable. Compound 1 is no substrate for adenosine deaminase.