Abstract: The present invention concerns a new general process for asymetric hemisynthesis of harringtonines and their analogs, that are alcaloids used in chimiotherapy. This process comprises direct esterification of a natural cephalotaxine with an acylating compound constituted of a side chain precursor which backbone and fonctionalization are entirely preformed.

Abstract: The present invention concerns a compound of formula (I) wherein: W represents O or NH, Q represents an unbranched or branched, saturated or unsaturated or aromatic, cyclic or acyclic or heterocyclic hydrocarbon radical containing 1 to 30 carbon atoms including or not heteroatom(s), R1 is H, OH, or OMe, O-(C1-C30)-alkyl, O-aryl-(C1-C30)-alkyl, O-(C2-C30)-alkenyl, O-(C3-C30)-cycloalkyl or null, and R2 is H or OH, or R1 and R2 form together —O—, R3=R4=OMe or R3 and R4 form together —OCH2O—, R is H, C1-C30 alkyl or O-protecting group and R6 represents an unbranched or branched, saturated or unsaturated or aromatic, cyclic or acyclic or heterocyclic hydrocarbon radical containing 1 to 30 carbon atoms including or not heteroatom(s), or R and R6 form together —CMe2—, n is 0 to 8, R5 is H, OH, OMe, O-(C1-C30)-alkyl, O-aryl-(C1-C30)-alkyl, O-(C2-C30)-alkenyl, O-(C3-C30)-cycloalkyl or O-aryl, the dotted line is null or forms a double bond dep