This compound can be prepared in two different ways: 1) The reaction of alpha-trifluoromethylacrylonitrile (I) with HBr in ethanol gives alpha-trifluoromethyl-beta-bromopropionamide (II), which is condensed with acetylurea (A) in hot aqueous dioxane to yield alpha-trifluoromethyl-beta-(N-acetylureido)propionamide (III). The cyclization of (III) with aqueous HCl at 120 C affords 5,6-dihydro-5-trifluoromethyluracil (IV), which is brominated with Br2 in refluxing acetic acid to afford 5,6-dihydro-5-bromo-5-trifluoromethyluracil (V). The dehydrobromination of (V) in DMF at 135-45 C gives 5-trifluoromethyluracil (VI), which is condensed with 2-deoxy-alpha-D-ribose-1-phosphate (VII) by means of a nucleosidephosphorylase preparation, or an exchange reaction with thymidine catalyzed by an enzyme3 obtained from Escherichia Coli B. 2) The reaction of 5-trifluoromethyluracil (VI) with trimethylchlorosilane in refluxing hexamethyldisilazane gives bis(trimethylsilyl)-5-trifluoromethyluracil (VIII), which is condensed with 3,5-bis(O-p-nitrobenzoyl)-1,2-dideoxy-1-chloro-D-ribofuranose (IX) by means of mercuric acetate in benzene to afford 3',5'-bis-O-(p-nitrobenzoyl)-2'-deoxy-5-trifluoromethyluridine (X). Finally, this compound is hydrolyzed by treatment with diisopropylamine in refluxing methanol.

This compound can be prepared in two different ways: 1) The reaction of alpha-trifluoromethylacrylonitrile (I) with HBr in ethanol gives alpha-trifluoromethyl-beta-bromopropionamide (II), which is condensed with acetylurea (A) in hot aqueous dioxane to yield alpha-trifluoromethyl-beta-(N-acetylureido)propionamide (III). The cyclization of (III) with aqueous HCl at 120 C affords 5,6-dihydro-5-trifluoromethyluracil (IV), which is brominated with Br2 in refluxing acetic acid to afford 5,6-dihydro-5-bromo-5-trifluoromethyluracil (V). The dehydrobromination of (V) in DMF at 135-45 C gives 5-trifluoromethyluracil (VI), which is condensed with 2-deoxy-alpha-D-ribose-1-phosphate (VII) by means of a nucleosidephosphorylase preparation, or an exchange reaction with thymidine catalyzed by an enzyme3 obtained from Escherichia Coli B. 2) The reaction of 5-trifluoromethyluracil (VI) with trimethylchlorosilane in refluxing hexamethyldisilazane gives bis(trimethylsilyl)-5-trifluoromethyluracil (VIII), which is condensed with 3,5-bis(O-p-nitrobenzoyl)-1,2-dideoxy-1-chloro-D-ribofuranose (IX) by means of mercuric acetate in benzene to afford 3',5'-bis-O-(p-nitrobenzoyl)-2'-deoxy-5-trifluoromethyluridine (X). Finally, this compound is hydrolyzed by treatment with diisopropylamine in refluxing methanol.

This compound can be prepared in two different ways: 1) The reaction of alpha-trifluoromethylacrylonitrile (I) with HBr in ethanol gives alpha-trifluoromethyl-beta-bromopropionamide (II), which is condensed with acetylurea (A) in hot aqueous dioxane to yield alpha-trifluoromethyl-beta-(N-acetylureido)propionamide (III). The cyclization of (III) with aqueous HCl at 120 C affords 5,6-dihydro-5-trifluoromethyluracil (IV), which is brominated with Br2 in refluxing acetic acid to afford 5,6-dihydro-5-bromo-5-trifluoromethyluracil (V). The dehydrobromination of (V) in DMF at 135-45 C gives 5-trifluoromethyluracil (VI), which is condensed with 2-deoxy-alpha-D-ribose-1-phosphate (VII) by means of a nucleosidephosphorylase preparation, or an exchange reaction with thymidine catalyzed by an enzyme3 obtained from Escherichia Coli B. 2) The reaction of 5-trifluoromethyluracil (VI) with trimethylchlorosilane in refluxing hexamethyldisilazane gives bis(trimethylsilyl)-5-trifluoromethyluracil (VIII), which is condensed with 3,5-bis(O-p-nitrobenzoyl)-1,2-dideoxy-1-chloro-D-ribofuranose (IX) by means of mercuric acetate in benzene to afford 3',5'-bis-O-(p-nitrobenzoyl)-2'-deoxy-5-trifluoromethyluridine (X). Finally, this compound is hydrolyzed by treatment with diisopropylamine in refluxing methanol.