合成路线1

5-Formylsalicylic acid (I) is protected by esterification with H2SO4/MeOH to give the methyl ester (II). After alkylation of the phenolic hydroxyl group of (II) with propyl bromide, the resultant ortho-propoxy benzoate ester (III) is hydrolyzed to carboxylic acid (IV) with LiOH in aqueous THF. Condensation of the aldehyde-acid (IV) with 2,4-thiazolidinedione (V) in the presence of morpholine leads to the benzylidene thiazolidinedione (VI). Activation of the carboxyl group of (VI) with oxalyl chloride gives rise to the corresponding acid chloride (VII), which is then condensed with (S)-alpha-methylbenzylamine (VIII) to furnish the target amide.