合成路线1

Addition of thiocyanogen (generated in situ from KSCN and N-bromosuccinimide) to 3-fluoroaniline (I) gave the thiocyanoaniline (II). Subsequent acylation of aniline (II) with benzyl chloroformate afforded carbamate (III). The intermediate thiol produced by treatment of thiocyanate (III) with sodium sulfide was captured as the trityl sulfide (IV) upon quenching with bromotriphenylmethane. The chiral oxazolidinone (VI) was then obtained by condensation of the lithium salt of carbamate (IV) with (R)-glycidyl butyrate (V). Activation of the primary hydroxyl of (VI) as the corresponding mesylate (VII), followed by displacement with NaN3 in hot DMF gave rise to the alkyl azide (VIII). Removal of the S-trityl protecting group of (VIII) by means of trifluoroacetic acid and triisopropylsilane and further alkylation of the resultant thiol with iodomethane yielded the methyl sulfide (IX). Sulfoxide (X) was then obtained by oxidation of sulfide (IX) with m-chloroperbenzoic acid. Reduction of the azido group of (X) to the required amine (XI) was accomplished by treatment with triphenylphosphine followed by aqueous hydrolysis. Finally, condensation of amine (XI) with ethyl dithioacetate furnished the title thioacetamide.