Omacetaxine mepesuccinate is a cephalotaxine-derived alkaloid ester obtained from Cephalotaxus harringtonia; used for the treatment of chronic or accelerated phase chronic myeloid leukaemia. It has a role as an antineoplastic agent, a protein synthesis inhibitor, an apoptosis inducer and an anticoronaviral agent. It is an alkaloid ester, a tertiary alcohol, an organic heteropentacyclic compound and an enol ether. It is functionally related to a cephalotaxine.