Morpholine and Thiomorpholine: A Privileged Scaffold Possessing Diverse Bioactivity Profile

Morpholine and its thio analogue thiomorpholine are moieties with multifaceted roles, and demonstrated myriad physiological activity. This review discusses several analogues of morpholine and thiomorpholine synthesized by varied facile synthetic schemes resulting in substitution on multiple positions of the heterocycles. Both morpholine and its thio analogue have proven to act as bioactives against different molecular targets. These scaffolds have been an indispensable element of the pharmacophore and have exhibited selective enzyme inhibition against many receptors. They have also been an integral aspect of the drug discovery process. This review endeavours to condense the new trends concomitant to the various aspects of morpholine and thiomorpholine, their biological activities and their various synthetic routes.