Structural Aspects of mTOR Inhibitors: Search for Potential Compounds

mTOR (mammalian target of rapamycin) is a catalytic subunit composed of two multi-protein complexes that indicate mTORC1 and mTORC2. It plays a crucial role in various fundamental cell processes like cell proliferation, metabolism, survival, cell growth, etc. Various first line mTOR inhibitors such as Rapamycin, Temsirolimus, Everolimus, Ridaforolimus, Umirolimus, and Zotarolimus have been used popularly. In contrast, several mTOR inhibitors such as Gedatolisib (PF-05212384) are under phase 2 clinical trials studies for the treatment of triple-negative breast cancer. The mTOR inhibitors bearing heterocyclic moieties such as quinazoline, thiophene, morpholine, imidazole, pyrazine, furan, quinoline are under investigation against various cancer cell lines (U87MG, PC-3, MCF-7, A549, MDA-231). In this review, we summarized updated research related to mTOR inhibitors and their structure-activity relationship, which may help scientists develop potent inhibitors against cancer.