Triterpenoids from the leaves of Diospyros kaki (persimmon) and their inhibitory effects on protein tyrosine phosphatase 1B.
Phytochemical study on a methanol-soluble extract of the leaves of persimmon (Diospyros kaki) resulted in the isolation of two new ursane-type triterpenoids, 3alpha,19alpha-dihydroxyurs-12,20(30)-dien-24,28-dioic acid (1) and 3alpha,19alpha-dihydroxyurs-12-en-24,28-dioic acid (2), together with 12 known ursane- and oleanane-type triterpenoids (3-14). Triterpenoids with a 3beta-hydroxy group were found to inhibit protein tyrosine phosphatase 1B (PTP1B) activity, with IC50 values ranging from 3.1+/-0.2 to 18.8+/-1.3 microM, whereas those with a 3alpha-hydroxy moiety were not active.
Thuong
Phuong Thien
PT
College of Pharmacy, Chosun University, 375 Seosuk-dong, Dong-gu, Gwangju 501-759, Korea.
Lee
Chul Ho
CH
Dao
Trong Tuan
TT
Nguyen
Phi Hung
PH
Kim
Wan Gi
WG
Lee
Sang Jun
SJ
Oh
Won Keun
WK
D029788:Diospyros / Q000737:chemistry*; D006801:Humans; D007723:Korea; D015394:Molecular Structure; D018515:Plant Leaves / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1 / Q000037:antagonists & inhibitors*; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology
C532941:3alpha,19alpha-dihydroxyurs-12,20(30)-dien-24,28-dioic acid; C532940:3alpha,19alpha-dihydroxyurs-12-en-24,28-dioic acid; D014315:Triterpenes; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1