Three acetylated flavonol glycosides from Forsteronia refracta that specifically inhibit p90 RSK.
A survey of plant extracts for the presence of p90 ribosomal S6 kinase (RSK) inhibitors resulted in the isolation of three acetylated flavonol glycosides. Kaempferol 3-O-(2'',4''-O-diacetyl-alpha-l-rhamnopyranoside) (1), kaempferol 3-O-(3'',4''-O-diacetyl-alpha-l-rhamnopyranoside) (2), and kaempferol-3-O-(4''-O-acetyl-alpha-l-rhamnopyranoside) (3) were isolated from Forsteronia refracta as the first RSK inhibitors. Of these, compound 2 was found to be the best inhibitor with an IC(50) value of 89 nM.
Xu
Ya-Ming
YM
Departments of Chemistry and Biology, University of Virginia, Charlottesville, VA 22901, USA.
Smith
Jeffrey A
JA
Lannigan
Deborah A
DA
Hecht
Sidney M
SM
D000107:Acetylation; D029062:Apocynaceae / Q000737:chemistry*; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D044948:Flavonols / Q000737:chemistry / Q000494:pharmacology*; D006027:Glycosides / Q000737:chemistry / Q000494:pharmacology*; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D038744:Ribosomal Protein S6 Kinases, 90-kDa / Q000037:antagonists & inhibitors*; D013045:Species Specificity; D013237:Stereoisomerism
D004791:Enzyme Inhibitors; D044948:Flavonols; D006027:Glycosides; D010936:Plant Extracts; D038744:Ribosomal Protein S6 Kinases, 90-kDa