Morpholine: Pharmacophore Modulating Pharmacokinetic Properties of Anticancer Leads

The morpholine ring is considered the most preferred and versatile heterocylic ring in medicinal chemistry due to its distinctive mechanistic activities that give it various biological activities. The eminence of the morpholine ring to modulate the pharmacokinetic properties of the compound, further makes it a fundamental pharmacophore in developing lead molecules. Multi-drug resistance in cancer leads to discovering selective and potent chemotherapeutic agents. Researchers are designing and synthesizing morpholine derivatives as potential anticancer drugs those act by targeting various signaling pathways driven by various protein kinases in the cell, i.e. Ras-Raf-MEK-ERK (ERK) and PI3K/Akt/mTOR, thereby inhibiting cell proliferation and growth. The potency of natural and synthetic derivatives of morpholine makes it a drug of choice for cancer treatment. Many of the morpholine containing anticancer drugs are under clinical trials. Hence, morpholine ring synthesis also becomes a central target for various scientists using green synthesis by straightforward one-step methods. A substantial literature is available on synthetic techniques of morpholine and substituted morpholine. The present chapter updates diverse new synthetic strategies of the morpholine ring and morpholine derivatives with potent anticancer activity. The chapter will also highlight the clinical data of morpholine derivatives with anticancer activity and mechanism of action. The latest information on novel anticancer morpholine derivatives with structural activity relationship (SAR) is also included. This chapter provides information about the necessary structural modifications required in drugs' chemical structure and contribute to the anticancer drug discovery program.

Keywords: Anticancer, Morpholine, Pharmacokinetic, PI3K/Akt/mTOR, Protein kinase, Ras-Raf-MEK-ERK (ERK), Structure-activity relationship (SAR).