title: Rhododendric acid A, a new ursane-type PTP1B inhibitor from the endangered plant Rhododendron brachycarpum G. Don.
abstract: In spite of the critical role of the natural products in drug discovery, surprising little attention has been placed on endangered and rare plant species that could play a pivotal role in pharmaceutical and fiber development. Protein tyrosine phosphatase-1B (PTP1B), which blocks insulin signaling, has been gaining interest to be a promising therapeutic target for the treatment of type 2 diabetes mellitus. Bioassay-guided fractionation on the leaves of Rhododendron brachycarpum G. Don (Ericaceae) yielded seven PTP1B inhibitory triterpenoids, including a new triterpene, rhododendric acid A (1). Their PTP1B inhibitory potency and their lipophilicity were investigated to provide a feasible scaffold that may overcome the innate limitation of the previously reported PTP1B inhibitors.
authors.affiliation: College of Pharmacy, Yeungnam University, Gyeongsan, Gyeongbuk 712-749, Republic of Korea.
authors.forename: Yeon Ho
authors.initials: YH
authors.lastname: Choi
authors.forename: Wei
authors.initials: W
authors.lastname: Zhou
authors.forename: Joonseok
authors.initials: J
authors.lastname: Oh
authors.forename: Sanggil
authors.initials: S
authors.lastname: Choe
authors.forename: Dong Woo
authors.initials: DW
authors.lastname: Kim
authors.forename: Seung Ho
authors.initials: SH
authors.lastname: Lee
authors.forename: Minkyun
authors.initials: M
authors.lastname: Na
mesh_terms: D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D029791:Ericaceae / Q000737:chemistry*; D015394:Molecular Structure; D018515:Plant Leaves / Q000737:chemistry*; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1 / Q000037:antagonists & inhibitors* / Q000378:metabolism; D011994:Recombinant Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D014315:Triterpenes / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D004791:Enzyme Inhibitors; D011994:Recombinant Proteins; D014315:Triterpenes; C577885:rhododendric acid A; C516607:PTPN1 protein, human; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1