Nelumal A, the active principle from Ligularia nelumbifolia, is a novel farnesoid X receptor agonist
摘要:
A series of 29 oxyprenylated and azoprenylated phenylpropanoids were chemically synthesized and tested in transfected cultured HepG2 cells by means of the dual-luciferase assay as farnesoid X receptor (FXR) agonists, using the endogenous ligand chenodeoxycholic acid (CDCA) as reference drug. Among the tested molecules, three compounds, namely auraptene, nelumol A, and nelumal A showed a potency comparable to the endogenous ligand, with the latter natural product having a level of activity slightly superior to CDCA. Nelumal A is thus of interest as a valuable potential novel lead compound in the search for FXR agonists. (C) 2012 Elsevier Ltd. All rights reserved.
Palladium-Catalyzed Mono-<i>N</i>-allylation of Unprotected Anthranilic Acids with Allylic Alcohols in Aqueous Media
作者:Hidemasa Hikawa、Yuusaku Yokoyama
DOI:10.1021/jo201691e
日期:2011.10.21
Palladium-catalyzed N-allylation of anthranilic acids 1a-j with allyl alcohol 2a in the presence of Pd(OAc)(2), sodium diphenylphosphinobenzene-3-sulfonate (TPPMS) in THF-H2O at room temperature gave only mono-N-allylated anthranilic acids 3a-j in good yields (70-98%). The reactions of 4-bromoanthranilic acid 1i with 2-methyl-3-buten-2-ol 2b showed complete chemoselectivity in N-allylation (neutral conditions) and C-vinylation (basic conditions). In our catalytic system, the keys to success are use of an unprotected anthranilic acid as a starting material and the presence of water in the reaction medium. The carboxyl group of anthranilic acid and water may play important roles for the smooth generation of the pi-allyl palladium species by activation of the hydroxyl group of the allylic alcohol.