A series of phosphorylated flavonoids were synthesized and investigated in vitro as inhibitors of pancreatic cholesterol esterase (CEase) and acetylcholinesterase (AChE). The results showed that most of the synthesized compounds exhibited nanomolar potency against CEase, much better than the parent flavonoids. Furthermore, these phosphorylated flavonoids demonstrated good to high selectivity for CEase over AChE, which only showed micromolar potency inhibition of AChE. The most selective and potent inhibitor of CEase (3e) had IC50 value of 0.72 nM and 11800-fold selectivity for CEase over AChE. The structure activity relationships revealed that the free hydroxyl group at position 5 and phosphate group at position 7 of the phosphorylated flavonoids are favorable to the inhibition of CEase. The inhibition mechanism and kinetic characterization studies indicated that they are irreversible competitive inhibitors of CEase. (C) 2014 Elsevier Masson SAS. All rights reserved.
A new synthesis of fully phosphorylated flavones as potent pancreatic cholesterol esterase inhibitors
Five flavones possessing one to four phenolic groups were fully phosphorylated efficiently and the obtained compounds showed excellent pancreatic cholesterol esterase (CEase) inhibitory activities with IC50 in the nanomolar range, which were much more potent than their parent compounds. The inhibition mechanism and kinetic characterization studies indicate that they are irreversible competitive inhibitors.