第二篇Methicillin-Resistant Staphylococcus aureus (MRSA)-Active Metabolites from Platanus occidentalis (American Sycamore)Mohamed A. Ibrahim, Arsala A. Mansoor, Amanda Gross, M. Khalid Ashfaq, Melissa Jacob, Shabana I. Khan and Mark T. Hamann*Departments of Pharmacognosy, Pharmacology, Chemistry, and Biochemistry and National Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, Mississippi 38677, and Triton Biopharma LLC, 213 Timber Lane Oxford, Mississippi 38655J. Nat. Prod., 2009, 72 (12), pp 21412144DOI: 10.1021/np900499qPublication Date (Web): November 11, 2009Copyright 2009 The American Chemical Society and American Society of Pharmacognosy* To whom correspondence should be addressed. Tel: +1 662-915-5730. Fax: +1 662-915-6975. E-mail: mthamannolemiss.edu., Department of Pharmacognosy, The University of Mississippi., National Center for Natural Products Research, The University of Mississippi., Departments of Pharmacology, Chemistry and Biochemistry, The University of Mississippi., Triton Biopharma LLC.Abstract：One known and three new potent, selective, and nontoxic anti-MRSA metabolites, kaempferol 3-O-l-(2,3-di-E-p-coumaroyl)rhamnoside (1) (IC50 2.0 g/mL), kaempferol 3-O-l-(2-E-p-coumaroyl-3-Z-p-coumaroyl)rhamnoside (2) (IC50 0.8 g/mL), kaempferol 3-O-l-(2-Z-p-coumaroyl-3-E-p-coumaroyl)rhamnoside (3) (IC50 0.7 g/mL), and kaempferol 3-O-l-(2,3-di-Z-p-coumaroyl)rhamnoside (4) (IC50 0.4 g/mL), were isolated from the leaves of the common American sycamore, Platanus occidentalis. Compounds 24 are new. Due to the unusual selectivity, potency, and safety of the pure compounds and the semipure glycoside mixture against MRSA, it is clear that this represents a viable class of inhibitors to prevent growth of MRSA on surfaces and systemically.从普通的美国梧桐叶中分离出了一种已知的和三种新的有效的、选择性强的、无毒的可以抑制耐甲氧西林金黄色葡萄球菌代谢物的山奈酚3-O-l-(2,3-di-E-p-coumaroyl)rhamnoside (1) (IC50 2.0 g/mL), kaempferol 3-O-l-(2-E-p-coumaroyl-3-Z-p-coumaroyl)rhamnoside (2) (IC50 0.8 g/mL), kaempferol 3-O-l-(2-Z-p-coumaroyl-3-E-p-coumaroyl)rhamnoside (3) (IC50 0.7 g/mL), and kaempferol 3-O-l-(2,3-di-Z-p-coumaroyl)rhamnoside (4) (IC50 0.4 g/mL)。化合物24是新的。纯化合物特殊的选择性，效能、和安全性以及配糖体混合物抑制MRSA的能力表明它们是抑制MRSA增长的有效抑制剂。第三篇第四篇第五篇第六篇ArticleDiterpenoid, Steroid, and Triterpenoid Agonists of Liver X Receptors from Diversified Terrestrial Plants and Marine SourcesHiranthi Jayasuriya, Kithsiri B. Herath, John G. Ondeyka, Ziqiang Guan, Robert P. Borris, Suroojnauth Tiwari, Wil de Jong, Flor Chavez, Jeremy Moss, Dennis W. Stevenson, Hans T. Beck, Marc Slattery, Nelson Zamora, Marvin Schulman, Aisha Ali, Neelam Sharma, Karen MacNaul, Nancy Hayes, John G. Menke, and Sheo B. Singh*Merck Research Laboratories, P.O. Box 2000, Rahway, New Jersey 07065, Institute of Economic Botany, The New York Botanical Garden, Bronx, New York 10458, National Center for Natural Products Research, The University of Mississippi, University, Mississippi 38677, and Instituto Nacional de Biodiversidad (INBio), Heredia, Costa Rica J. Nat. Prod., 2005, 68 (8), pp 12471252DOI: 10.1021/np050182gPublication Date (Web): August 10, 2005Copyright 2005 American Chemical Society and American Society of PharmacognosyAbstract:It has been demonstrated that liver X receptors (LXR) play a significant role in cholesterol homeostasis. Agonists of LXR are expected to increase cellular cholesterol efflux, lower LDL, and raise HDL levels. Screening of a natural product library of plant extracts using a LXR-SPA binding assay and bioassay-guided fractionation of a number of plant and marine gorgonian extracts led to the isolation of a number of active compounds. These included acanthoic acid (1) and alcohol (2), viperidone (3), polycarpol (4), rosacea acid (5), a cycloartane derivative (6), a new cycloartane analogue (7), betulinic acid (8), and gorgostane derivatives (9, 10, and 11). Of these compounds, 1, 4, and 11 exhibited potent binding affinity for -receptor with IC50 values of 0.25, 0.12, and 0.07 M, respectively. Functionally they also showed strong coactivator association stimulation for LXR receptor with EC50 values of 0.18, 0.03, and 0.05 M, respectively. They also exhibited 15-, 8-, and 13-fold induction of the -receptor in a transactivation assay in HEK-293 cells, respectively. In general these compounds were selective for the LXR -receptor over the -receptor in all assays and were much better stimulators of the -receptor than the endogenous steroid ligands.