Structure-based design of inhibitors of purine nucleoside phosphorylase. 2. 9-Alicyclic and 9-heteroalicyclic derivatives of 9-deazaguanine.

Alicyclic and heteroalicyclic derivatives of 9-deazaguanine (2-amino-1,5-dihydro-4H-pyrrolo[3,2-d] [pyrimidin-4-one) are, with one exception, potent inhibitors of purine nucleoside phosphorylase (PNP) equaling the corresponding 9-arylmethyl derivatives previously investigated. The mode of binding of these compounds to PNP was determined by X-ray crystallography.