Thirteen 3-substituted benzothiazolone derivatives have been synthesized. Their chemical structures have been elucidated by IR and NMR spectral data and by elemental analyses. Among these compounds, 1-¿3-[2(3H)-benzothiazolon-3-yl[propanoyl]morpholine (5b); 1-¿3-[2(3H)-benzothiazolon-3-yl[propanoyl]-4-benzylpiperidine++ + (5c); 1-¿3-[2(3H)-benzothiazolon-3-yl[-propanoyl]-4-phenylpiperazine (5d); 3-[3-(4-benzylpiperidine-1-yl)propyl]-2(3H)-benzothiazolone (5k); 3-[3-(4-benzylpiperazine-1-yl)propyl]-2(3H)-benzothiazolone (5I); 3-[3-(4-phenylpiperazine-1-yl)propyl]-2(3H)-benzothiazolone (5m) have been found to be significantly more active than the others.