ABSTRACT
Using column chromatographic and preparative HPLC technologies, we isolated a new sesquiterpene glycoside from the stem of Dendrobium nobile. With spectroscopic techniques including NMR and MS, the new compound was identified as cadalene-12-O-β-D-glucopyranoside. This type of compound was dehydrogenated from cadinane sesquiterpene to achieve a naphthalene ring, and it is rare from a natural resource.
ABSTRACT
The chemical constituents of Litsea coreana were investigated using chromatographic methods, including column chromatography on silica gel, MCI, and semi-preparation HPLC. Two compounds were isolated and identified as hawktealignan A (1) and cinnamophilin (2) by NMR analyses as well as their physical and chemical properties. Compound 1 is a new lignan and compound 2 was isolated from this plant for the first time.
ABSTRACT
To study the chemical constituents of the fruits of Fructus carotae, silica gel column chromatography and preparative HPLC were used to isolate and purify the extract of Fructus carotae. The structures of obtained compounds were elucidated on the basis of physicochemical property and spectral data. Nine guaiane-type sesquiterpenes were isolated and identified as 8β-angeloyloxy-11-hydroxy-4-guaien-3-one(1), 11-acetoxy-4-guaien-3-one(2), 11-acetoxy-8β-isobutyryl-4-guaien-3-one(3), 11-acetoxy-8β-propionyl-4-guaien-3-one(4), 11-hydroxy-4-guaien-3-one(5), 11-acetoxy-8β-angeloyloxy-1β-hydroxy-4-guaien-3-one(6), 11-acetoxy-8β-angeloyloxy-4-guaien-3-one(7), 11-acetoxy-8β-hydroxy-4-guaien-3-one(8)and 8β,11-dihydroxy-4-guaien-3-one(9). Compound 1 is a new compound, compound 5 is a new natural product, and compounds 2-4 were isolated from this genus for the first time.
ABSTRACT
In this study, seven bibenzyl compounds were isolated from the stem of Dendrobium nobile by silica gel, MCI column chromatographic and preparative HPLC technology. By using spectroscopic techniques including NMR and MS, these compounds were identified as 4, α-dihydroxy-3, 5, 3'-trimethoxybibenzyl (1), 4, 5-dihydroxy-3, 3', α-trimethoxybibenzyl (2), 4, 4'-dihydroxy-3, 5, 3'-trimethoxybibenzyl (3), 4, 5-dihydroxy-3, 3'-dimethoxybibenzyl (4), 4, 3'-dihydroxy-3, 5-dimethoxybibenzyl (5), 5, 4'-dihydroxy-3, 3'-dimethoxybibenzyl (6) and 5, 3'-dihydroxy-3-methoxybibenzyl (7). Compound 1 is a new compound and compound 4 was isolated from this plant for the first time.
ABSTRACT
Objective: To further study the chemical constituents of Clematoclethra scandens subsp. actinidioides. Methods: The compounds were isolated and purified by chromatographic methods such as silica gel column chromatography and preparative HPLC, and their structures were identified on the basis of physicochemical properties and spectral data. Results: Nineteen compounds were isolated and identified as vulgarsaponin A (1), 9-hydroxy-megastigma-4,7-dien-3-one-9-O-β-D-glucopyranoside (2), kaempferol-3-O- α-L-rhamnpyranoside (3), quercetin-3-O-α-L-rhamnopyranoside (4), quercetin-3-O-β-D-glucopyranoside (5), hyperoside (6), 1,3,6-tri-O-galloyl-β-D-glucopyranoside (7), 1,2,3,6-tetra-O-galloyl-β-D-glucopyranoside (8), catechin (9), gallocatechin (10), procyanidin B3 (11), protocatechuic acid (12), syringic acid (13), vanillic acid (14), 7-oxokaurenolide (15), stigmast-3,6-dione (16), stigmast-4-en-3,6-dione (17), taraxerol (18), and β-sitosterol (19). Conclusion: Compounds 1-12, and 16 are isolated from the plant of Clematoclethra Maxim. for the first time.
ABSTRACT
Objective: To further study the chemical constituents of Gymnotheca chinensis. Methods: The compounds were isolated and purified by silica gel column chromatography and preparative HPLC, and their structures were elucidated by spectral analysis. Results: Sixteen compounds were isolated and identified as 2-(1-hydroxy-4-oxo-cyclohexa-2,5-dienyl)-acetonitrile (1), N-benzoyl-2-hydroxyltyramine (2), N-benzoyltyramine (3), N-benzoyl-2-phenylethylamine (4), 7,4'-dimethoxykaemferol (5), nobiletin (6), tangeretin (7), curculonone A (8), 6-hydroxy-4,7-megastigmadien-3,9-dione (9), 5,6-epoxy-3-hydroxy-7-megastigmen-9-one (10), 9-hydroxy-4-megastigmen-3-one (11), 9-hydroxy-4,7-megastigmadien-3-one (12), loliolide (13), 6β-hydroxy-stigmasta-4-en-3-one (14), 6β-hydroxy- stigmasta-4,22-dien-3-one (15), and 3β-hydroxy-stigmasta-5-ene-7-one (16). Conclusion: Compounds 1 and 2 are new natural products, and the others are isolated from this genus for the first time.
ABSTRACT
Objective: To investigate the chemical constituents of Dendrobium nobile from Guizhou province. Methods: The constituents were isolated and purified by silica gel, MCI column chromatography, and preparative HPLC technology. The structure of the isolated compound was elucidated by MS and NMR spectra. Results: A new sesquiterpene, identified as δ-cadinen-12,14-diol (1), was isolated from the stem of D. nobile. Conclusion: Compound 1 is a new compound.
ABSTRACT
A new ursane-type triterpenoid saponin, 2α,3α,24-trihydroxyurs-12,20(30)-dien-28-oic acid β-D-glucopyranosyl ester (1), together with six known triterpenoid saponins, was isolated and characterized from the aerial parts of Clematoclethra scandens subsp. actinidioides.
Subject(s)
Actinidiaceae , Chemistry , Molecular Structure , Plant Components, Aerial , Chemistry , Plant Extracts , Chemistry , Plants, Medicinal , Chemistry , Saponins , TriterpenesABSTRACT
To study the chemical constituents of Clematoclethra scandens subsp. actinidioides, chromatographic methods such as silica gel and MCI column chromatographic technology, and preparative HPLC were used and sixteen compounds were isolated from the aerial parts of this plant. By using spectroscopic techniques including 1H, 13C-NMR, HMBC and ESI-MS, these compounds were identified as betulinic acid (1), ursolic acid (2), oleanic acid (3), corosolic acid (4), 3beta-(trans-p-coumaroyloxy)-2alpha, 23-dihydroxyurs-12-en-28-oic acid (5), 3beta-(trans-p-coumaroyloxy)-2alpha, 23-dihydroxyurs-12, 20 (30)-dien-28-oic acid (6), 2alpha, 3alpha, 23-trihydroxyurs-12, 20 (30)-dien-28-oic acid (7), 2alpha, 3alpha, 23-trihydroxyurs-12-en-28-oic acid (8), asiatic acid (9), 2alpha, 3alpha, 24-tri-hydroxyurs-12-en-28-oic acid (10), 2alpha, 3beta, 23-trihydroxyurs-12, 20 (30)-dien-28-oic acid (11), 2alpha, 3beta, 19alpha, 24-tetrahydroxyurs-12-en-28-oic acid (12), 2alpha, 3alpha, 19alpha, 24-tetrahydroxyurs-12-en-28-oic acid (13), 2alpha, 3beta, 23, 24-tetrahydroxyurs-12-en-28-oic acid (14), 2alpha, 3alpha, 19alpha, 23, 24-pentahydroxyurs-12-en-28-oic acid (15) and daucosterol (16). Among them, compounds 3-6, 11-12, 14 and 15 were isolated from this endemic plant for the first time.