合成路线1

Sodium azide (I) is treated with sulfuric acid to give hydrazoic acid (II), which is condensed with 1-tetralone (III) in hot aqueous sulfuric acid yielding 2,3,4,5-tetrahydro-1H-1-benzazepin-2-one (IV). The bromination of (IV) with Br2 in chloroform affords the 3-bromo derivative (V), which is treated with sodium azide in DMSO to give the corresponding azido derivative (VI). The condensation of (VI) with ethyl 2-bromoacetate (VII) by means of KOH and tetrabutylammonium bromide in THF yields the adduct (VIII). The azido group of (VIII) is reduced with H2 over Pd/C in ethanol the amine (IX) as a racemic mixture, which is submitted to optical resolution with L-tartaric acid affording the desired (S)-enantiomer (X). The condensation of intermediate (X) with 2(R)-benzyl-3-benzyloxyamino)propionic acid (XI) by means of HOBT and EDAC in dichloromethane provides the amide (XII), which is formylated with formic acid and acetic anhydride yielding the formamide (XIII). The debenzylation of (XIII) with H2 over Pd/C in methanol affords the intermediate (XIV), which is finally hydrolyzed with NaOH in methanol.