Page 183 - Phytochemistry 2 (06-PG 605)
P. 183
Structure requirements for cytotoxic activity of
Cucurbitacins
1- α,β- unsaturated double bond at C23- C24 increases
cytotoxic activity.
2- keto groupat C-3 increases the activity. Its reduction,
reduces thecytotoxic activity.
3- Introduction of an acetyl group at C-25 increases the
cytotoxic activity.
4- double bond at C 1- C 2 may increase
the activity.
5- Introduction of a hydroxyl group at C-24 decreases the activity.
Cucurbitacin E is a compound containing 1, 2- double
bond, 23, 24 double bond, 3-keto group and an acetyl
group at C-25 , it is the highlycytotoxic cucurbitacins.
