Hydrochloric Acid → 2,6-Diaminopurine

Participants

Reaction Steps

9-(R) -2-phosphonomethoxypropyl) -2-amino-6-azidopurine (0.30 g, prepared according to Example 27) in 50% aqueous methanol (200 ml) containing hydrochloric acid (0.5 ml) was hydrogenated over 10% Pd/C (0.5 g) overnight at room temperature. The mixture was filtered, washed with water, filtrate alkalized with ammonia and evaporated in vacuo. The residue was deionized on a column of Dowex 50×8 (50 ml) (cf. Example 25) and the ammonia eluate evaporated to dryness. The residue in water (pH adjusted to 9) was applied on a column of Dowex 1×2 (acetate) which was first washed with water to remove salts and the product was then eluted with 1 M acetic acid. The fractions containing product were pooled, evaporated to dryness and codistilled with water (3×20 ml). The residue was crystallized from water (ethanol added to turbidity) to afford 9-(R)-2-phosphonomethoxypropyl)-2,6-diaminopurine (120 mg) identical with the preparation according to Example 19.

Provenance & Evidence