EFFICIENT SYNTHESES OF (E)-5-(2-BROMOVINYL)-2'-DEOXY-4'-THIOURIDINE -A NUCLEOSIDE ANALOG WITH POTENT BIOLOGICAL-ACTIVITY

(E)-5-(2-Bromovinyl)-2'-deoxy-4'-thiouridine (S-BVDU) is a potent anti herpesvirus agent and its use in gene therapy as an anticancer agent h as recently been described. We here outline 2 efficient methods for th e synthesis of S-BVDU. The decision as to which method is to be used d epends upon the starting materials available but starting from BVU, an overall yield of beta-nucleoside of 35% can be expected. From 5-ethyl -2'-deoxy-4'-thiouridine, radical bromination using bromine will give a quantitative conversion to S-BVDU if unreacted starting material is recycled (50%) or using N-bromosuccinimide, a one step yield in excess of 80% can be obtained.