Antitumoral compounds

A compound of general formula I

• wherein Y is CHRay—CRby ═CRcy
• each Ray, Rby, and Rcy is independently selected from hydrogen and unsubstituted C1-C12 alkyl;
• each R1, R2, R3, R4, and R5 is independently selected from hydrogen and unsubstituted C1-C12 alkyl;
• R6 is NR8R9;
• A is
• W is NR7;
• R7 is hydrogen;
• R8 is hydrogen;
• each dotted line represents an optional additional bond, but when a triple bond exists between the C atoms to which R1 and R2 are attached, R1 and R2 are absent, and when a triple bond exists between the C atoms to which R3 and R4 are attached, R3 and R4 are absent;
• R9 is selected from substituted or unsubstituted C2-C12 alkenyl and substituted or unsubstituted C4-C12 alkenynyl wherein the optional substituents are selected from halogen atoms and OR′, wherein R′ is hydrogen, silyl-ether protecting group or CONR″R″ wherein each R″ is independently selected from hydrogen and C1-C6 alkyl;
• each R16, R17 and R18 are independently selected from hydrogen and ORa;
• R19 is hydrogen;
• and
• Ra is unsubstituted C1-C12 alkyl;
• or a pharmaceutically acceptable salt, tautomer or stereoisomer thereof.