ChemInform Abstract: 2‐β‐D‐Ribofuranosylbenzoxazole from 2,5‐Anhydro‐D‐allonoimidate, and 1,3‐Dimethyl‐8‐β‐D‐ribofuranosylxanthine from 2,5‐Anhydro‐D‐allono‐ thioimidates and ‐dithioates.

Abstract

353ChemInform Abstract The reaction between the imidates (I) and the aminophenol (II) yields the benzoxazole (III) only. The trimethylxanthine (VII) can be prepared by reacting (Ia) with (IV) via the intermediate (V) or by cyclization of the dithioester (VI) with (IV). The carbohydrate derivatives (X) and (XI), prepared by the Pinner procedure, are converted to the corresponding derivatives (XII) -(XV) in a similar manner. Aromatization of the furanose ring takes place in the reaction of (Xd) and (Xf) with (IV) to produce (XIII). (IR-and 1H-NMR-data).