Patent ID: 8455540

Claim:
A compound of general formula (1) in which R 1b and R′ 1b are each independently methyl, ethyl, n-propyl, n-butyl, t-butyl, s-butyl, pentyl or hexyl, R 2b and R′ 2b are each independently a linear or branched alkyl with 1 to 6 carbon atoms, optionally substituted, or an ester, R 3 and R′ 3 are each independently a hydrogen, CHO, CR 8 ═NR 9 or C(O)OR 10 group in which R 8 , R 9 and R 10 are independently a hydrogen atom or a linear or branched alkyl with 1 to 20 carbon atoms, optionally substituted, or a linear or branched alkenyl with 2 to 20 carbon atoms, optionally substituted; and R 4 , R′ 4 , R 5 , R′ 5 , R 6 and R′ 6 are each a hydrogen, or a protective group of the hydroxy function, gossypol, apogossypol and the compounds in which simultaneously R 1b , R′ 1b are ethyl and R 2b , R′ 2b are methyl being excluded, or one of its enantiomers, or one of its salts, or a salt of one of its enantiomers.