Alkyl ether derivatives (I) are new. Alkyl ether derivatives of formula (I) and their salts are new. [Image] R 1, R 2 : H, halo, optionally substituted alkyl, aryl, aralkyl, alkoxy, aryloxy, alkylthio, arylthio, alkenyl, alkenyloxy, alkylsulfonyl, arylsulfonyl, carbamoyl, heterocyclyl, NO 2, oxo or optionally protected hydroxy, amino or carboxyl; R 3 : optionally substituted alkylamino or optionally protected amino or hydroxy; A : 5 or 6 membered heteroaryl or benzene; m, n : 1-6; and p : 1-3. ACTIVITY : Calcium-Antagonist. MECHANISM OF ACTION : Neuroprotective; CNS-Gen. In nerve regeneration models in SD rats 1-{3-[2-(1-benzothiophen-5-yl)ethoxy]propyl}-3-azetidinol (Ia) hydrochloric acid salt administered at 1 mg/kg/day orally for 13 days increased regeneration by 186% compared to a control.