Antiviral and antischistosomal evaluation of newly synthesized thioglycosides and their acyclic analogues.

The pyrimidine thione derivatives 2a-d were prepared by the reaction of thiourea, ethyl cyanoacetate and several aromatic aldehydes. The acyclic thioglycosides 4a-7d were prepared by the reaction of the synthesized pyrimidine thiones 2a-d with different alkyl halides, whereas the reaction of 2a-d with 2,3,4,6-tetra-O-acetyl-alpha-D-glucopyranosyl bromide afforded the cyclic thioglycosides 8a-d whose deprotection afforded 9a-d. The obtained compounds were tested for their antischistosomal and antiviral activity against hepatitis B virus (HBV). Compounds 5a, 5d, 7a showed high activity against HBV using the MTT assay; moreover compounds 5c, 6d, 7a, 9a, 9c exhibited high activity as antischistosomal agents.