Regioselective synthesis of 3(n(1,3dioxo1Hbenzo[de] isoquinolin-2(3H)-yl)alkyl) -2-(4-substituted) phenylthiazolidine -4-carboxylic acid were performe d by coupling of 2-aryl-thiazolidin-4-caboxylic aci ds respectively with N-( ω -bromoalkyl)-1,8-naphthalimideusing K 2 CO 3 in DMF medium. The structure of all the new compoundswere characterized by IR, 1 H-NMR, 13 C-NMR, and Mass spectral data.