Euphane Triterpenes from the Bark of Broussonetia papyrifera

Abstract

Four new euphane triterpenes, (3b)-3-(acetyloxy)eupha-7,25-dien-24-one (1), (3b,24R)-3-(acetyloxy)eupha-7,25-dien-24-ol (2), (3b,24S)-eupha-7,25-diene-3,24-diol (3), and (3b,24R)-eupha-7,25-diene-3,24-diol (4) were isolated from the barks of Broussonetia papyrifera, a tree whose roots, barks, and fruits were used as herbal drugs in China. The structures of 1 -4 were elucidated on the basis of spectroscopic evidence and chemical methods.Introduction. -Broussonetia papyrifera (Linn. ) Vent., belonging to the family Moraceae, has a wide distribution in China. The roots, barks, and fruits are all used in Chinese traditional and herbal drugs [1]. Previous phytochemical investigations of this plant have resulted in the isolation of flavonols, coumarins, and 1,3-diphenylpropanes [2 -4]. In a previous study, we isolated three alkaloids from this plant with aglycosidase-inhibiting activities as a part of our search for bioactive compounds from natural resources [5]. In this article, we describe the isolation and structural elucidation of four new euphane triterpenoids.

Three Novel Triterpenoids from Taraxacum officinale Roots

“…Residue C was rechromatographed over silica gel to give a triterpene fraction, which was subjected to HPLC (ODS, 95% MeOH) to afford compounds 1 (1.38 mg) and 9 (1.12 mg) [16]. Residue D was rechromatographed over silica gel to give a triterpene fraction, which was subjected to HPLC (ODS, 95 % MeOH) to afford compounds 2 (1.60 mg), 3 (2.40 mg), 5 (1.61 mg) [17], 8 (1.39 mg) [18], and 10 (2.82 mg) [19]. Residue L was rechromatographed over silica gel to give a triterpene fraction, which was subjected to HPLC (ODS, 95% MeOH) to afford compounds 4 (20.23 mg) [5] and 7 (1.06 mg) [5].…”

Tetracyclic Triterpenoids, Steroids and Lignanes from the Aerial Parts of <i>Oxypetalum caeruleum</i>

“…The residues of the ether-soluble fraction and the water-soluble fraction were subjected to silica gel column chromatography and semi-preparative HPLC to give nine tetracyclic triterpenoids, two pregnanes, one pregnane glycoside, three lignanes and two lignane glycosides. Compounds 3S,24S,25-trihydroxy-tirucall-7-ene (6), 8,9) (3β,24S)-euph-7,25-diene-3,24-diol (7), 10) (3β,24R)-euph-7,25-diene-3,24-diol (8), 10) 3β-hydroxy-cycloart-23-ene-25methylester (9), 11,12) cortexone (10), 13) 6,7-didehydrocortexone (11), 14) (+)-pinoresinol (13), 15,16) (+)-medioresinol (14), 16) and (−)-syringaresinol (15) 16,17) were identified as shown in Chart 1 based on the 1 H-and 13 C-NMR spectroscopic data. This paper described the structural elucidation of new compounds from this plant.…”

Progress in Chemical Constituents and Bioactivities of Broussonetia pa-pyrifera (L.) Vent

“…[14][15][16] Besides, broussochalcone B (12), 3,4-dihydroxyisolonchocarpin (13), 4-hydroxyisolonchocarpin (14), kazinol E (15), 8-(1,1-dimethylallyl)-5'-(3-methylbut-2-enyl)-3',4',5,7-tetrahydroxyflanvonol (16), brossoflurenone A (17) and brossoflurenone B (18) were isolated from roots, in which compounds 17 and 18 were two novel benzofluoreneones. [17] Besides the above-mentioned compounds, flavonoids and their glycosides were also isolated from the fruits and leaves of B. papyrifera, which were named apigenin (19), apigenin-7-Oβ-D-glucopyranoside (20), broupapyrin A (21), cosmosiin (22), luteolin-7-O-β-D-glucopyranoside (23), and apigenin-6-C-β-Dglucopyranside (24). Compound 21 was a new isoprenylated flavonol [18] and 24 was isolated from the leaves for the first time.…”

“…Among them, compounds 26-30 were five new tetracyclic triterpenoids. [14,[21][22][23] The structures are shown in Figure 2. .…”