Synthesis of 2',3'-dideoxynucleosides by enzymatic trans-glycosylation.

Recently, several pyrimidine and purine 2',3'-dideoxynucleosides have been shown to inhibit the replication of the human immunodeficiency virus-1 (HIV), the causative agent of the acquired immune deficiency syndrome (AIDS). These compounds are usually prepared by reduction of the corresponding 2'-deoxynucleosides. The present experiments demonstrate that 2',3'-dideoxynucleosides can also be made by enzymatic trans-glycosylation, using the trans-N-deoxyribosylase from Lactobacillus helveticus. The broad specificity of this enzyme makes it possible to synthesize for metabolic studies radiochemically pure 2',3'-dideoxynucleosides, using diverse purine and pyrimidine base acceptors.