合成路线1

The reaction of 3,4-dihydro-1H-2-benzopyran (VII) with benzoyl chloride and ZnCl2 gives benzoic acid 2-[2-(chloromethyl)phenyl]ethyl ester (XIII), which is condensed with hexamethylenetetramine (XIV) yielding the amminium salt (XV). The hydrolysis of (XV) affords 2-(2-benzoyloxyethyl) benzaldehyde (XVI), which is condensed with nitromethane as before to give the nitrostyrene (XVII). The cyclization of (XVII) with FeCl3 and acetyl chloride as before yields 4-(2-benzoyloxyethyl)-3-chloroindolin-2-one (XVIII), which is dechlorinated with hydrazine and Pd/C to the indolinone (XIX). The hydrolysis of (XIX) with NaOH affords 4-(2-hydroxyethyl)indolin-2-one (XX), which is acylated with TsCl giving the tosylate (XXI). Finally, this compound is condensed with dipropylamine (II).