Phytoconstituents from the rhizomes of Curcuma aromatica Salisb.

Phytochemical investigation of the chloroform extract of the rhizomes of Curcuma aromatica Salisb. (Zingiberaceae) yielded three new phytoconstituents characterized as n-heneitriacontan-14-one; n-pentatriacontan-5-one; 11α-cyclopentyl-n-decan-1-ol (curcumapentadecanol) along with the known compounds stigmasterol and n-nonacosan-1-ol. The structures of these phytoconstituents have been elucidated on the basis of structural data analysis and chemical reactions.     

Cytotoxic dimeric sesquiterpenoids from Curcuma parviflora: isolation of three new parviflorenes and absolute stereochemistry of parviflorenes A, B, D, F, and G

Three novel dimeric sesquiterpenoids, named parviflorenes G-I (1-3), have been isolated from Curcuma parviflora (Zingiberaceae), and their structures were elucidated by means of spectroscopic studies. Absolute stereochemistry of parviflorene G (1) as well as previously isolated related compounds, parviflorenes A (4), B (5), D (6), and F (7), was revealed by CD spectral data and chemical means. Parviflorenes G (1) and I (3) were cytotoxic against HeLa cells, while parviflorenes A (4) and F (7) were cytotoxic against all tested tumor cell lines in the human cancer cell line panel assay.     

Parviflorenes B-F, novel cytotoxic unsymmetrical sesquiterpene-dimers with three backbone skeletons from Curcuma parviflora

Five novel natural products classified as dimeric sesquiterpenes, named parviflorenes B-F (2-6), possessing three types of novel backbone frameworks, have been isolated from Curcuma parviflora (Zingiberaceae). The structures of 2-6 were elucidated by means of spectroscopic studies, and the structure of 2 was further unambiguously established by X-ray crystallographic analysis. Compounds 2, 4, and 6 have an unsymmetrical bis-cadinane skeleton, while compound 3 is a dimer of cadinane and iso-cadinane, and compound 5 possesses another novel carbon framework consisting of two cadinanes with different bond-connection. These new compounds with novel carbon skeletons showed cytotoxicity against tumor cell lines.     

Gas chromatography-mass spectrometry coupled with pseudo-Sadtler retention indices, for the identification of components in the essential oil of Curcuma longa L.

Gas chromatography-mass spectrometry was applied to the cyclohexane extract of Curcuma longa L. The chromatographic conditions generated retention indices very close i.e., greater than 99.9%, to those reported for structures in the Sadtler Standard Gas Chromatography Retention Index Library. In addition to the extensively reported sesquiterpene ketones, this essential oil extract contained a series of saturated and unsaturated fatty acids. Wiley mass spectra library matching for the free fatty acids, their trimethylsilyl esters and methyl esters narrowed their identity down to a few candidates. Combining this information with the retention indices of the fatty acid methyl esters in the Sadtler library allowed the identification of some of the double bond positions.     

Parviflorene A, a novel cytotoxic unsymmetrical sesquiterpene-dimer constituent from Curcuma parviflora

A novel natural sesquiterpene-dimer-type compound, named parviflorene A (1), was isolated from the extract of a tropical Zingiberaceous plant, Curcuma parviflora, collected in Thailand, and its structure was elucidated by spectral data. Parviflorene A (1) possesses an unprecedented unsymmetrical bis-cadinane skeleton and exhibited cytotoxic activity against murine leukemia P388 and B16 melanoma cells.     

Two new diterpene and sesquiterpene from Pteris dispar

A new diterpene and a new sesquiterpene were isolated from Pteris dispar and identified on the basis of spectral data including 2D NMR.Compounds 1 and 2 showed potent cytotoxic activity against KB cell.     

Leucospilotaside C, a new sulfated triterpene glycoside from sea cucumber Holothuria leucospilota

A new triterpene glycoside, leucospilotaside C, along with two known saponin, was isolated from sea cucumber Holothuria leucospilota collected from the South China Sea, and its structure was elucidated as 3-0-{4′-O-sodiumsulfate-β′-D-xylopyranosyl}- holosta-22,25-epoxy-9-ene-3β,12α,17α-triol （1） by extensive spectroscopic analysis and chemical methods. The glycosides have the same triterpene aglycone, but differ in the oligosaccharide moieties.     

Two new dammarane-type sapogenins from Gynostemma pentaphyllum

Two new sapogenins,named(20S,24R)-3β,20,21β,25-tetrahydroxy-21,24-cyclodammarane(1)and 3β-hydroxyetio-17β-dammaranic acid(2),were isolated from the alkaline hydrolysate of Gynostemma pentaphyllum saponins.Their structures were elucidated by spectroscopic methods.     

Two new lanostane triterpenoids from Abies sachalinensis

The continuous chemical investigation on the ethyl acetate （EtOAc） soluble fraction of the MeOH extract afforded two new lanostane triterpenoid derivatives including one with a rearranged lanostane skeleton. They were identified as 3,4-seco-8-（14→13R）abeo-17,13-friedo-9β-lanosta-4（28）, 7,14（30）,24-tetraen-26,23-olide-23-hydroxy-3-oic acid （1） and 7,14-mariesa- dien-3oL-hydroxy-25-methoxy-26-oic acid （2）. Structural determination of these compounds were carried out by the spectral studies especially by the two digital （2D）-NMR and high-resolution MS experiences.     

ααTwo new eudesmane sesquiterpenes from Lactuca sativa var. anagustata L

Two new eudesmane sesquiterpene lactones were isolated from the stalk of Lactuca sativa var.anagustata L and their structureswere elucidated by means of spectroscopic methods,including 2D NMR(~1H-~1H COSY,HMBC and NOESY) as 1β-O-β-D-glucopyranosyl-4α-hydroxyl-5α,6β,11βH-eudesma-12,6α-olide(1) and 1β-hydroxyl-15-O-(p-methoxyphenylacetyl)-5α,6β,11βH-eudesma-3-en-12,6α-olide(2).     

The chemical constituents from Schisandra propinqua var. intermedia

A new cinnamic acid monoterpenoid ester, intermedin C （1）, was isolated from the aerial parts of Schisandra propinqua var. interthedia. The structure of 1 was elucidated by spectroscopic methods including extensive ^1D and 2D NMR techniques.     

Two new prenylflavonoids from Morus nigra L.

Two new prenylflavonoids, mornigrol E(1) and mornigrol F(2) were isolated from Morus nigra L. Their structures were elucidated on the basis of spectroscopic methods, especially 2D-NMR techniques.     

Prepatellamide A, a new cyclic peptide from the ascidian Lissoclinum patella

A new cyclic peptide, prepatellamide A (1), along with three known cyclic peptides (2)— (4), was isolated from the ascidianLissoclinum patella. The structure of prepatellamide A was determined from one- and two-dimensional¹H and¹³C NMR spectra. The known cyclic peptides were identified as patellamides A (2), B (3) and C (4).     

A new oxo-sterol derivative from the rhizomes of Costus speciosus

Chemical investigation of the rhizomes of Costus speciosus led to the isolation of a new compound, 22-ketocholesteryl palmitate (1) along with four known compounds, 24-methylenecycloartanol (2), cycloartanol (3), stigmasterol (4) and linoleic acid (5). The structure of new compound was characterised by extensive 1D-, 2D-NMR and mass spectrometry (GC-MS and HR-ESI-MS) techniques.     

Salviskinone A, a diterpene with a new skeleton from Salvia przewalskii

A novel compound, named salviskinone A (1), was isolated from Salvia przewarskii. The compound has a rearranged carbon skeleton with a methyl unit at C-5 from abietane-type diterpene. Its structure and relative stereochemistry were elucidated by detailed spectroscopic analysis, including HREIMS and 2DNMR (COSY, HSQC, HMBC, and NOESY) spectra.     

Colensolide A: a new nitrogenous bromophenol from the New Zealand marine red alga Osmundaria colensoi

A new nitrogenous bromophenol, colensolide A, is isolated from the New Zealand red alga Osmundaria colensoi together with the known bromophenol lanosol and four of its derivatives. In this study, a novel technique is employed to identify potentially new compounds in semi-purified mixtures containing a plethora of structurally similar, known metabolites, using NMR spectroscopy. The structure and relative configuration of colensolide A is determined using standard spectroscopic techniques. Several of the known bromophenols exhibit antibacterial activity and one shows moderate cytotoxicity.     

Triterpene Glycosides from Cussonia paniculata. I. Isolation and Structure Determination of Glycosides A, B1, B2, C, D, G2, H1, and H2 from Leaves of Cussonia paniculata

The 3-O-β-D-glucopyranoside of β-sitosterol (1) and the known triterpene glycosides 3-O-α-L-arabinopyranosides of oleanolic (2a) and ursolic (2b) acids and hederagenin (3), 3-O-β-D-glucopyranosyl-(1→2)-α-L-arabinopyranosideofoleanolic acid (4), 3-O-α-L-arabinopyranosyl-28-O-α-L-rhamnopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosides of oleanolic (5a) and ursolic (5b) acids and the newglycoside 28-O-α-L-rhamnopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranoside of 23-hydroxyursolic acid (6) were isolated from leaves of Cussonia paniculata (Araliaceae). Their structures were established using chemical methods and NMR spectroscopy.__________Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 160–163, March–April, 2005.     

A new triterpenoid saponin from the leaves and stems of Panax quinquefolium L.

One new triterpenoid saponin,quinquenoside L_(17)(1),was isolated from the leaves and stems of Panax quinquefolium L.,and its structure was elucidated as 20-O-[(β-D-xylopyranosyl-(1-6)-O-β-D-glucopyranosyl)]-6-O-β-D-glucopyranosyl-dammar-24-ene- 3,6,12,20-tetraol,by the combination analysis of one-dimensional NMR and two-dimensional NMR,mass spectrometry,CD spectrum and chemical evidences.     

Benzocoumarins from the rhizomes of Juncus acutus

Investigation of the ethyl acetate extract of Juncus acutus rhizomes revealed seven benzocoumarins, probably derived from oxidation of phenanthrenes already isolated from the plant. The structures were determined by means of spectroscopic methods. The anti-algal activity of the isolated compounds tested on the green alga Pseudokirchneriella subcapitata are reported here.