title: Emodin, a protein tyrosine kinase inhibitor from Polygonum cuspidatum.
abstract: Bioassay-directed fractionation of a Chinese medicinal plant, Polygonum cuspidatum (Polygonaceae), has led to the discovery of an anthraquinone, emodin [1], as a strong inhibitor of a protein tyrosine kinase (p56lck) partially purified from bovine thymus. Comparison of the IC50 values of emodin for protein tyrosine kinase inhibitory activity with physcion [2] and emodin-O8-D-glucoside [3], also isolated from the same plant, reveal the importance of the hydroxyl groups at C-6 and C-8 for the observed activity.
authors.affiliation: Department of Medicinal Chemistry and Pharmacognosy, Purdue University, West Lafayette, Indiana 47907.
authors.forename: H
authors.initials: H
authors.lastname: Jayasuriya
authors.forename: N M
authors.initials: NM
authors.lastname: Koonchanok
authors.forename: R L
authors.initials: RL
authors.lastname: Geahlen
authors.forename: J L
authors.initials: JL
authors.lastname: McLaughlin
authors.forename: C J
authors.initials: CJ
authors.lastname: Chang
mesh_terms: D000818:Animals; D002417:Cattle; D004642:Emodin / Q000302:isolation & purification / Q000494:pharmacology*; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck); D010946:Plants, Medicinal / Q000737:chemistry*; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors*
chemical_list: D011505:Protein-Tyrosine Kinases; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck); D004642:Emodin