2003 Nucleic acids

Nucleic acidsU 0700 Synthesis of 1-β-D-(5-Deoxy-5-iodoarabinofuranosyl)-2-nitroimidazole

(β-IAZA): A Novel Marker of Tissue Hypoxia. — The β-anomer of IAZA, (VII), is synthesized using an unconventional route from AZR, (I), including an inversion of configuration at C-2' of the protected sugar (II). β-AZA (VI) can be obtained by two pathways. Using an alternative procedure, (IV) is desilylated first to give the arabino-furanosyl derivative (V), that upon deacetylation affords (VI). β-AZA (VI) undergoes iodination with triphenylphosphine and iodine via an alkoxytriphenylphosphonium in-termediate to yield the target compound (VII). In view of the low yield of (VII), the modified route starts from (V) by placing a suitable leaving group at C-5', which is eas-ily substitutable by iodide to form the target (VII) in a better yield. — (KUMAR, P.; OHKURA, K.; BEIKI, D.; WIEBE, L. I.; SEKI*, K.-I.; Chem. Pharm. Bull. 51 (2003) 4, 399-403; Fac. Pharm. Sci., Health Sci. Univ. Hokkaido, Ishikari, Hokkaido 061, Japan; Eng.) — H. Hoennerscheid

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