Disclosed is a compound of formula (I): wherein ‘D’, ‘E’, ‘m’, ‘n’ and R1-R4 are as described herein, as a modulator of nicotinic acetylcholine receptors particularly the α7 subtype, in a subject in need thereof, as well as analogues, prodrugs, isotopically substituted analogs, metabolites, pharmaceutically acceptable salts, polymorphs, solvates, isomers, clathrates, and co-crystal thereof, for use either alone or in combinations with suitable other medicaments, and pharmaceutical compositions containing such compounds and analogues. Also disclosed are a process of preparation of the compounds and the intended uses thereof in therapy, particularly in the prophylaxis and therapy of disorders such as Alzheimer's disease, mild cognitive impairment, senile dementia, and the like.