合成路线1

A new synthesis of T-3761 has been described: The esterification of 2,3,4,5-tetrafluorobenzoic acid (I) with ethyl bromide and K2CO3 in DMSO gives the corresponding ethyl ester (II), which is condensed with tert-butyl cyanoacetate (III) by means of K2CO3, yielding 4-(cyanomethyl)-2,3,5-trifluorobenzoic acid ethyl ester (V) through the intermediate (IV). The cyclopropanation of (V) with 1,2-dibromoethane and benzyltriethylammonium chloride and NaOH in water/dichloromethane affords 4-(1-cyanocyclopropyl)-2,3,5-trifluorobenzoic acid, which by treatment with H2O2 and NaOH is converted to 4-(1-carbamoylcyclopropyl)-2,3,5-trifluorobenzoic acid (VII). Degradation of amide (VII) with Cl2 and NaOH gives the corresponding 4-aminocyclopropyl derivative (VIII), which is acetylated with acetic anhydride to the acetamide (IX). The reaction of (IX) with SOCl2 yields the acid chloride (X), which is condensed with malonic acid monoethyl ester potassium salt (XI) by means of triethylamine to afford 2-[4-(1-acetamidocyclopropyl)-2,3,5-trifluorobenzoyl]acetic acid ethyl ester (XII). The consecutive reaction of (XII) first with dimethylformamide dimethylacetal (XIII) in acetic acid and then with 2(S)-aminopropanol (XIV) gives the benzoylacrylic intermediate (XV), which, without isolation, is treated with K2CO3 in DMSO at 100 C to afford the ethyl ester of the acetylated T-3761 (XVI). Finally, this compound is deprotected by successive treatment first with ethanolic NaOH and then with hot 6N HCl.