A stilbene dimer, andalasin B, from the root trunk of Morus macroura

Abstract

The oligostilbenoids isolated from members of the Dipterocarpaceae, Gnetaceae, Vitaceae, and Leguminosae are of interest because they exhibit antimicrobial and cytotoxic activity. 1,2 Prenylated stilbenes, Diels-Alder adducts, and prenylated 2-arylbenzofurans also occur in members of the Moraceae. [3][4][5] Recently, andalasin A(1), 6 a stilbene dimer, and macrourin B (2), 7 a benzofuran-stilbene derivative, were isolated from the heartwood and tree bark, respectively, of Morus macroura Miq. In addition, another stilbene dimer, artogomezianol, was characterised from a member of the allied genus, Artocarpus gomezianus. 8 In our search for further oligostilbenes from moraceaous plants, we have examined the root trunk of M. macroura. We now report the isolation of a new stilbene dimer, which we have named andalasin B (3), along with the known phenolic compounds 1, lunularin, oxyresveratrol, and β-resorcylaldehyde.The dried powdered root trunk of M. macroura was macerated with MeOH, and the MeOH-extract was partitioned into hexane, CH 2 Cl 2 , and EtOAc soluble fractions. The EtOAc fraction was fractionated using silica gel chromatography and the fraction rich in phenolic compounds and more polar than oxyresveratrol, was repeatedly purified by radial chromatography to give compounds 1 and 3. Using the same methodology, lunularin and β-resorcylaldehyde were isolated from the CH 2 Cl 2 fraction. Compound 3, obtained as brownishyellow solid, had a molecular formula C 28 H 22 O 8 [[M] + ion at m/z 486.1332 (calcd. 486.1315)]. The UV spectrum of 3 (see Experimental) showed absorption maxima characteristic of a stilbene chromophore. The IR spectrum of 3 exhibited absorptions for hydroxyl and aromatic functionalities. A dimeric stilbenoid structure was suggested by this data for compound 3. The 1 H NMR spectrum of 3 resembles those of ε-viniferin 9 and the resveratrol (E)-dehydrodimer (4), 10 and revealed signals assignable to two 3,5-dihydroxyphenyl (δ

The Herbal DrugMelampyrum pratenseL. (Koch): Isolation and Identification of Its Bioactive Compounds Targeting Mediators of Inflammation

“…This compound is mainly known from liverworts [46, 47]. Besides, in higher plants, it was found in celery, Apium graveolens [48], and Morus species [49]. Activity studies have only been conducted concerning antibacterial, antifungal, and antioxidant characteristics [50], but the anti-inflammatory effects of lunularin have not yet been reported.…”

Impact of Environmental Factors on Stilbene Biosynthesis

“…Stilbenes are often accumulated in plants as oligomers (oligostilbenes) resulting from the oxidative coupling of stilbene monomers [157,158]. Oligostilbenes have been isolated from species belonging to different plant families including Vitaceae [159], Fabaceae [160], Cyperaceae [161], Dipterocarpaceae [162], Gnetaceae [163], Paeoniaceae [164], Iridaceae [165], and Moraceae [166]. The interest addressed to oligostilbenes in recent decades is linked to their important biological role in the plant as phytoalexins [167], to their chemical diversity with more than 200 different molecules known to date [158], and to the wide spectrum of biological activities such as β-secretase inhibitory, anti-influenza virus, and anti-herpes simplex virus activities [168].…”

Inventory, Constituents and Conservation of Biologically Important Sumatran Plants

“…Andalas is also another name for the island of Sumatra, and is used as the name of the university. From the heart-wood of this plant, andalasin A (47) was isolated [50], while andalasin A (47), andalasin B (48), lunularin (49) and oxyresveratrol (50) were found in the root trunk [51].…”