合成路线1

Treatment of 3-methoxy-2-cyclohexen-1-one (I) with n-butyllithium and diisopropylamine in THF, followed by addition of N,N-dimethylmethylene ammonium iodide (Eschenmoser's salt) (II) and precipitation with maleic acid, furnishes maleate (III). Methylation of (III) with iodomethane in DMF, followed by condensation with 2-methylimidazole (IV), affords compound (V), which is then converted into methylphenyl hydrazino derivative (VII) by first treatment with HCl in H2O followed by reaction with 1-methyl-1-phenylhydrazine (VI). Cyclization of (VII) is then performed by means of ZnCl2 in HOAc at 85 C to give carbazolone (VIII), and finally the target product is obtained by formation of the hydrochloride dihydrate salt.