0000000000239930
AUTHOR
Luis B. Rojas
New Triterpenoid and Ergostane Glycosides from the Leaves of Hydrocotyle umbellata L.
Two new triterpenoid glycosides, together with two new ergostane glycosides, umbellatosides A–D (1–4, resp.), have been isolated from the leaves of Hydrocotyle umbellata L. Their structures were established by 2D-NMR spectroscopic techniques (1H,1H-COSY, TOCSY, NOESY, HSQC, and HMBC) and mass spectrometry as 3β,22β-dihydroxy-3-O-[α-L-rhamnopyranosyl-(12)-β-D-glucuronopyranosyl]olean-12-en-28-oic acid 28-O-β-D-glucopyranosyl ester (1), 3-O-[α-L-rhamnopyranosyl-(12)-β-D-glucuronopyranosyl]oleanolic acid 28-O-β-D-glucopyranosyl ester (2), (3β,11α,26)-ergosta-5,24(28)-diene-3,11,26-triol 3-O-(β-D-glucopyranosyl)-11-O-(α-L-rhamnopyranosyl)-26-O-β-D-glucopyranoside (3), and (3β,11α,21,26)-ergosta…
Steroidal saponins from the fruits of Solanum torvum
Abstract Seven steroidal glycosides have been isolated from the fruits of Solanum torvum Swartz. Their structures were established by 2D NMR spectroscopic techniques ( 1 H, 1 H-COSY, TOCSY, NOESY, HSQC, and HMBC) and mass spectrometry as (25 S )-26-(β- d -glucopyranosyloxy)-3-oxo-5α-furost-20(22)-en-6α-yl- O -β- d -xylopyranoside ( 1 ), (25 S )-26-(β- d -glucopyranosyloxy)-3-oxo-22α-methoxy-5α-furostan-6α-yl -O -β- d -xylopyranoside ( 2 ), (25 S )-26-(β- d -glucopyranosyloxy)-3β-hydroxy-22α-methoxy-5α-furostan-6α-yl- O -α- l -rhamnopyranosyl-(1 → 3)-β- d -glucopyranoside ( 3 ), (25 S )-3β-hydroxy-5α-spirostan-6α-yl- O -β- d -xylopyranoside ( 4 ), (25 S )-3-oxo-5α-spirostan-6α-yl- O -β- d -x…
Triterpene Saponins from the Fruits of Phytolacca rugosa (Phytolaccaceae)
Four known serjanic acid glycosides were isolated from the fruits of Phytolacca rugosa and characterized mainly by 2D NMR spectroscopy and mass spectrometry. This aglycon has a chemotaxonomic significance for the genus Phytolacca.
Acylated oleanane-type saponins from Ganophyllum giganteum
Abstract Five oleanane-type saponins , 3- O -β- D -glucuronopyranosylzanhic acid 28- O -β- D -xylopyranosyl-(1→3)-[α- L -rhamnopyranosyl-(1→2)]-(4- O -acetyl)-β- D -fucopyranosyl ester ( 1 ), 3- O -β- D -glucopyranosylzanhic acid 28- O -β- D -xylopyranosyl-(1→3)-[α- L -rhamnopyranosyl-(1→2)]-(4- O -acetyl)-β- D -fucopyranosyl ester ( 2 ), zanhic acid 28- O -β- D -xylopyranosyl-(1→3)-[α- L -rhamnopyranosyl-(1→2)]-(4- O -acetyl)-β- D -fucopyranosyl ester ( 3 ), zanhic acid 28- O -α- L -rhamnopyranosyl-(1→2)-4- O -[(3′-hydroxy-2′-methyl-butyroyloxy)-3-hydroxy-2-methyl-butyroyloxy]-β- D -fucopyranosyl ester ( 4 ), medicagenic acid 28- O -α- L -rhamnopyranosyl-(1→2)-4- O -[(3′-hydroxy-2′-methyl-…
New Steroidal Alkaloids from Solanum Hypomalacophyllum
Two new steroidal alkaloids (1-2) have been isolated from the leaves and roots of Solanum hypomalacophyllum Bitter, respectively. Their structures have been elucidated as deacetoxysolaphyllidine-3- O-β-D-glucopyranoside (1) and 4-keto-5,6-dihydro-(20 S)-verazine (2). Furthermore, two known steroidal alkaloids, 20 R-verazine and 20 S-verazine, and the common secondary metabolites oleanolic acid and β-sitosterol were isolated from the roots, whereas deacetoxysolaphyllidine was obtained from the leaves.
Steroidal Saponins from the Fruits of Cestrum ruizteranianum
Seven spirostane and furostane-type glycosides were isolated from the aqueous methanolic extract of the fruits of Cestrum ruizteranianum and characterized mainly by 2D NMR spectroscopy and mass spectrometry. These known saponins belong to the Δ5-spirostene and Δ5-furostene series and are reported in this species for the first time.
Triterpene saponins from Billia rosea.
Five previously undescribed triterpene saponins, billiosides A-E, and a known analogue, were isolated from the seeds of Billia rosea (Planch. & Linden) C. Ulloa & P. Jorg. Their structures were elucidated on the basis of extensive 1D and 2D NMR experiments (1H, 13C, DEPT, COSY, TOCSY, NOESY, ROESY, HSQC, and HMBC) and mass spectrometry as (3β,21β,22α)-3-[(2-O-β-D-glucopyranosyl-O-[α-L-arabinopyranosyl-(1 → 4)]-β-D-glucopyranosyl)oxy]-21-[((2E,6S)-2,6-dimethyl-6-hydroxyocta-2,7-dienoyl)oxy]-22-(acetyloxy)-24-hydroxyolean-12-en-28-oic acid, (3β,21β,22α)-3-[(2-O-β-D-galactopyranosyl-β-D-glucopyranosyl)oxy]-21,22-dihydroxyolean-12-en-28-yl O-α-L-arabinopyranosyl-(1 → 4)-β-D-glucopyranoside, (3β…
Oleanane-type glycosides from Pittosporum tenuifolium “variegatum” and P. tenuifolium “gold star”
Abstract The phytochemical study of two cultivars of Pittosporum tenuifolium Banks & Sol. ex Gaertn, “variegatum” and “gold star”, led to the isolation of eight oleanane-type glycosides: seven previously undescribed and a known one. Their aglycons are oxygenated oleanane derivatives as barringtogenol C, camelliagenin A, hederagenin, and 22α-hydroxyoleanolic acid. Their structures were established by 2D NMR spectroscopic techniques and mass spectrometry as 3-O-β-D-galactopyranosyl-(1 → 2)-[α-L-arabinopyranosyl-(1 → 3)]-β-D-glucuronopyranosyl-21-O-angeloyl-22-O-acetylbarringtogenol C, 3-O-β-D-galactopyranosyl-(1 → 2)-[α-L-arabinopyranosyl-(1 → 3)]-β-D-glucuronopyranosyl-21,22-di-O-angeloylbar…
Two New Oleanane-type Saponins from Hydrocotyle multifida
A phytochemical study of a Venezuelan species Hydrocotyle multifida led to the isolation of five oleanane-type glycosides: two previously undescribed and three known ones. Their structures were established by 2D NMR spectroscopic techniques and mass spectrometry as 3- O-β-D-galactopyranosyl-(1→2)-[α-L-arabinopyranosyl-(1→3)]-β-D-glucuronopyranosyloleanolic acid and 3- O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-(1→2)-β-D-glucuronopyrano-syloleanolic acid. These results represent a significative contribution to the chemotaxonomy of the Hydrocotyle genus.