5-(acylethynyl)uracils, 5-(acylethynyl)-2 '-deoxyuridines and 5-(acylethynyl)-1-(2-hydroxyethoxy)methyluracils. Their synthesis, antiviral and cytotoxic activities

5-(acylethynyl)uracils 4 were synthesized from 5-iodo-2,4-dimethoxypyrimidi ne 1 through a palladium-catalyzed reaction with acetylenic carbinols 5, su bsequent oxidation with manganese dioxide in dichloromethane, demethylation with 6 N hydrochloric acid, followed by treatment with sodium hydroxide in 95% ethanol. The corresponding 5-acylethynyl-2'-deoxyuridines 9 and 5-acyl ethynyl-1-(2-hydroxyethoxy-methyl)uracils 13 were synthesized following a s imilar procedure. The 5-acylethynyluracils 4 were cytotoxic against murine L1210 and human T-lymphocyte (Molt 4/C8, GEM) cells. The 2'-deoxyuridine de rivatives 9 were less cytotoxic; however the acyclonucleosides 13 were as a ctive as the free bases 4. The compounds did not have antiviral activities at subtoxic concentrations. (C) Elsevier, Paris.