The nucleophilic addition of the alkyl substituted bis(trimethylsilyl)ketene acetals to 2-(pyridin-3-yl)-1,3benzothiazole in the presence of triflic anhydride has been examined. The behavior of the chosen substrate in these transformations is peculiar due to an exclusive activation of its pyridine fragment, resulting in the exclusive formation of 3-benzothiazolyl-1,4-dihydropyridine carboxylic acids, as confirmed by single crystal Xray crystallography. These isolated acids have been efficiently turned into novel δ-bromolactones by the regioselective ring closing procedure promoted by NBS. In vitro cytotoxic activities of the synthetized carboxylic acids and lactones have shown moderate anticancer activity against six human tumor cell lines; the derivatives bearing a cyclobutyl group present the highest activity.