Benzophenones and xanthones from Garcinia cantleyana var. cantleyana and their inhibitory activities on human low-density lipoprotein oxidation and platelet aggregation.
Three benzophenones, 2,6,3',5'-tetrahydroxybenzophenone (1), 3,4,5,3',5'-pentahydroxybenzophenone (3) and 3,5,3',5'-tetrahydroxy-4-methoxybenzophenone (4), as well as a xanthone, 1,3,6-trihydroxy-5-methoxy-7-(3'-methyl-2'-oxo-but-3'-enyl)xanthone (9), were isolated from the twigs of Garcinia cantleyana var. cantleyana. Eight known compounds, 3,4,5,3'-tetrahydroxy benzophenone (2), 1,3,5-trihydroxyxanthone (5), 1,3,8-trihydroxyxanthone (6), 2,4,7-trihydroxyxanthone (7), 1,3,5,7-tetrahydroxyxanthone (8), quercetin, glutin-5-en-3β-ol and friedelin were also isolated. The structures of the compounds were elucidated by spectroscopic methods. The compounds were investigated for their ability to inhibit low-density lipoprotein (LDL) oxidation and platelet aggregation in human whole blood in vitro. Most of the compounds showed strong antioxidant activity with compound 8 showing the highest inhibition with an IC₅₀ value of 0.5 μM, comparable to that of probucol. Among the compounds tested, only compound 4 exhibited strong inhibitory activity against platelet aggregation induced by arachidonic acid (AA), adenosine diphosphate (ADP) and collagen. Compounds 3, 5 and 8 showed selective inhibitory activity on platelet aggregation induced by ADP.
Drug and Herbal Research Center, Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Malaysia. ibj@pharmacy.ukm.my
Ibrahim
I
Jantan
Fadlina Chany
FC
Saputri
D000328:Adult; D000368:Aged; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D001577:Benzophenones / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D029760:Garcinia / Q000737:chemistry*; D006801:Humans; D015227:Lipid Peroxidation / Q000187:drug effects*; D008077:Lipoproteins, LDL / Q000378:metabolism*; D008875:Middle Aged; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D013329:Structure-Activity Relationship; D044004:Xanthones / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D055815:Young Adult
D000975:Antioxidants; D001577:Benzophenones; D008077:Lipoproteins, LDL; D010975:Platelet Aggregation Inhibitors; D044004:Xanthones; C047723:benzophenone; C009689:xanthone