合成路线1

The reaction of 1,8-naphthoic anhydride (I) with hydroxylamine and NaOAc in water gives the N-hydroxynaphthalimide (II), which is condensed with 2,4-dinitrochlorobenzene (III) by means of Na2CO3 in hot water yielding the expected naphthalimide derivative (IV). The rearrangement of (IV) induced by NaOH in ethanol/water affords 8-amino-1-naphthoic acid (V), which is cyclized by means of sulfuric acid to the benz[cd]indolin-2-one (VI). The nitration of (VI) with HNO3 in acetic aid gives the expected 6-nitro derivative (VII), which is reduced with H2 over Pd/C in THF to the corresponding amino derivative (VIII). The condensation of (VIII) with the benzyl bromide (IX) by means of DIEA in hot DMF affords the secondary amine (X), which is methylated with methyl iodide and DIEA in hot DMF to provide the tertiary amine (XI). The reaction of the carbonyl group of (XI) with Lawesson's reagent gives the thione (XII), which is methylated with methyl iodide and NaOH to give the methylsulfanyl derivative (XIII). Finally, this compound is treated with ammonia in methanol.