合成路线1

Reaction of ethyl 2,3,4,5-tetrafluorobenzoate (I) with the anion of di-tert-butyl malonate followed by in situ decarboxylation with CF3CO2H affords ethyl 4-carboxymethyl-2,3,5-trifluorobenzoate (II), which is esterfied with diphenyldiazomethane to give ethyl 4-(diphenylmethoxycarbonylmethyl)-2,3,5-trifluorobenzoate (III). Compound (III) is treated with p-formaldehyde in the presence of sodium methoxide to give ethyl 4-[1-(diphenylmethoxycarbonyl)-2-hydroxyethyl]-2,3,5-trifluorobenzoate (IV), which is dehydrated with mesyl chloride and triethylamine to give ethyl 4-[1-(diphenylmethoxycarbonyl)vinyl]-2,3,5-trifluorobenzoate (V). Cyclopropanation of (V) with trimethylsulfoxonium iodide affords ethyl 4-(1-carboxycyclopropyl)-2,3,5-trifluorobenzoate (VII). Treatment of (VII) with ethyl chlorocarbonate and sodium azide followed by reaction with benzyl alcohol affords ethyl 4-[1-(benzyloxycarbonylamino)cyclopropyl]-2,3,5-trifluorobenzoate (VIII), which is hydrolyzed to 4-[1-(benzyloxycarbonylamino)cyclopropyl]-2,3,5-trifluorobenzoic acid (IX) on treatment with NaOH. Reaction of (IX) with magnesium ethoxycarbonylacetate and 1,1'-carbonyldiimidazole yields ethyl 4-[1-(benzyloxycarbonylamino)cyclopropyl]-2,3,5-trifluorobenzoylacetate (X) , which is then sequentially reacted with N,N-dimethylformamide dimethylacetal and (S)-2-amino-1-propanol to give (S)-ethyl 2-[4-[1-(benzyloxycarbonylamino)cyclopropyl]-2,3,5-trifluorobenzoyl]-3-(2-hydroxy-1-methylethylamino)acrylate (XI). Cyclization of (XI) with sodium hydride or with K2CO3 (2) affords (S)-ethyl 10-[1-(benzyloxycarbonylamino)cyclopropyl]-9-fluoro-3-methyl-7-oxo-2,3-dihydro-7H-pyrido[1,2,3-de][1,4]benzoxazine-6-carboxylate (XII), which is hydrolyzed on treatment with sodium hydroxide to give (S)-10-[1-(benzyloxycarbonylamino)cyclopropyl]-9-fluoro-3-methyl-7-oxo-2,3-dihydro-7H-pyrido[1,2,3-de][1,4]benzoxazine-6-carboxylic acid (XIII). Deprotection of (XIII) by hydrogenation over Pd in acetic acid, followed by treatment with hydrochloric acid, affords the monohydrochloride of T-3761 (XIV), which is finally converted to free T-3761 with potassium hydroxide.