合成路线1

The reaction of 5-methoxy-2-tetralone (I) with benzenethiosulfonic acid S-phenyl ester and sodium acetate in methanol gives 1,1-bis(phenylsulfanyl)-2-tetralone (II), which is condensed with 2-(bromomethyl)acrylic acid tert-butyl ester (III) by means of n-BuLi and diisopropylamine (DIA) in THF to yield the acrylic acid derivative (IV). Desulfurization of (IV) with Al/Hg in THF/water affords compound (V), which is treated with O-methylhydroxylamine and Na2HPO4 in methanol, providing the methoxyimino compound (VI). The reduction of (VI) with Zn/HOAc provides the methoxyamino compound (VII). The cyclization of (VII) by means of potassium hydrogen phosphate gives 1,6-dimethoxy-1,2,3,4,4a,5,10,10a-octahydrobenzo[g]quinoline-3-carboxylic acid tert-butyl ester as a diastereomeric mixture that is separated by chromatography to furnish the desired diastereomer (VIII). Hydrolysis of the tert-butoxy ester group of (VIII) by means of TFA yields the carboxylic acid (IX), which is treated with diazomethane to afford the methyl ester (X). Selective demethoxylation of (X) with Zn/HOAc provides the octahydrobenzoquinoline (XI).