New sesquiterpenes and calebin derivatives from Curcuma longa

One novel sesquiterpene with new skeleton, (6S)-2-methyl-6-(4-hydroxyphenyl-3-methyl)-2-hepten-4-one (1), two new bisabolane sesquiterpenes, (6S)-2-methyl-6-(4-hydroxyphenyl)-2-hepten-4-one (2), (6S)-2-methyl-6-(4-formylphenyl)-2-hepten-4-one (3), and two calebin derivatives, 4'-(4'-hydroxyphenyl-3'-methoxy)-2'-oxo-3'-butenyl-3-(4'-hydroxyphenyl)-propenoate (4) and 4'-(4'-hydroxyphenyl)-2'-oxo-3'-butenyl-3-(4'-hydroxyphenyl-3'-methoxy)-propenoate (5) were isolated along with five known bisabolane sesquiterpenes from Curcuma longa. 1-4 were new compounds and 5 was a new natural product. Their structures were established by spectral methods.     

Characterization, synthesis and self-aggregation of (-)-alternarlactam: a new fungal cytotoxin with cyclopentenone and isoquinolinone scaffolds

(-)-Alternarlactam [(-)-1], a new promising cytotoxin against two human cancer cell lines, was isolated from an endophyte culture and synthesized (along with (+)-1) from readily available starting materials. The absolute configuration, chirality-activity relevance and self-aggregation of (-)-1 were assigned by a combination of synthetic, spectroscopic and computational approaches. The full characterization of the new fungal cytotoxin may provide valuable information in the discovery of new antitumor agents.     

Studies on cytotoxic constituents in pericarps of Mallotus japonicus. IV

Two new phloroglucinol derivatives, isomallotolerin (1) and isomallotochromanol (2), were isolated from the cytotoxic fraction of the pericarps of Mallotus japonicus. The new derivatives were identified as 3-(3-methyl-2-hydroxybut-3-enyl)-5-(3-acetyl-2,4-dihydroxy-5-methy l-6- methoxybenzyl)-phlorisobutyrophenone (1) and 6-acetyl-5,7-dihydroxy-8-(3-acetyl-2,4-dihydroxy-5-methyl-6-methoxybenzy l)-2,2- dimethyl-3-hydroxychroman (2) from chemical and spectral data. Isomallotolerin and its acetate were found to be cytotoxic to KB cell line.     

New bisindole alkaloids isolated from Myxomycetes Arcyria cinerea and Lycogala epidendrum

Two new bisindole alkaloids, named cinereapyrrole A (1) and B (2), were isolated from wild fruit bodies of Arcyria cinerea and three new bisindole alkaloids (3-5) were isolated from wild fruit bodies of Lycogala epidendrum. Seven known bisindoles (6-12) were concomitantly obtained from them. The structures of the new compounds were elucidated by spectral data. Among these bisindole alkaloids, compound 12 showed cytotoxicity against cultured tumor cell lines.     

Studies on glycolipids. III. Glyceroglycolipids from an axenically cultured cyanobacterium, Phormidium tenue.

Seven new monogalactosyl diacylglycerols (1-7) and six new digalactosyl diacylglycerols (11-16) were isolated from an axenically cultured cyanobacterium, P. tenue. Their structures were elucidated on the basis of physicochemical evidence and the results of enzymatic hydrolysis using a lipase (from Rhizopus arrhizus). Comparison of antialgal activity for P. tenue between monogalactosyl diacylglycerols (1-8) and digalactosyl diacylglycerols (11-19) revealed that the former showed more potent activity than the latter.     

Three new dimeric benzofuran derivatives from the roots of Ligularia stenocephala MATSUM. et KOIDZ

Three new dimeric benzofuran derivatives, ligulacephalins A (1), B (2) and C (3), were isolated from the roots of Ligularia stenocephala MATSUM. ET KOIDZ. (Compositae) together with three known compounds, 5,6-dimethoxy-2-isopropenylbenzofuran (4), euparin (5) and (R)-(-)-hydroxytremetone (6). The structures of the new compounds were determined by spectroscopic evidence. The chiral HPLC analysis demonstrated that 1-3 occurred as a racemate. The absolute configurations of each enantiomer from 1-3 were elucidated on the basis of circular dichroism (CD) data.     

Lupane triterpenoids from Acacia mellifera with cytotoxic activity

Three new pentacyclic triterpenoids: (20R)-3-oxolupan-30-al (1), (20S)-3-oxolupan-30-al (2) and (20R)-28-hydroxylupen-30-al-3-one (3), along with (20S)-3beta-hydroxylupan-30-al (4), the latter previously described as a constituent of an epimeric mixture, were isolated from Acacia mellifera. In addition, the known metabolites 30-hydroxylup-20-(29)-en-3-one (5), 30-hydroxylup-20-(29)-en-3beta-ol (6), atranorin, methyl 2,4-dihydroxy-3,6 dimethyl benzoate, sitosterol-3beta-O-glucoside and linoleic acid were found in the analyzed plant species for the first time. The structures of the new metabolites were elucidated by extensive spectroscopic analyses and their relative stereochemistry was determined by NOESY experiments. The new metabolite 3 exhibited significant cytotoxic activity against the NSCLC-N6 cell line, derived from a human non-small-cell bronchopulmonary carcinoma.     

Two new compounds from Coriaria nepalensis

Two new compounds,corialins A(1) and B(2) were isolated from Coriaria nepalensis Wall.These new compounds were established as 7-hydroxy-3-[2,3-acetonide-(3-methylbutane)]coumarin(1) and 3-O-β-D-glucopyranosyl-3,4,5-trihydroxy-1-(3- methyl-2-butenyl)-benzene(2),on the basis of 1D and 2D NMR techniques.     

A new phenol compound from endophytic Phomopsis sp. DC01

The strain DC01 was isolated from the branch tissue of Daphniphyllum longeracemosum and determined to be a member of Phomopsis according to the ITS sequence analysis. The extracts from the PDA solid fermentation media of Phomopsis sp. DC01 were purified and three compounds including one new phenol compound were obtained. The new compound was identified to be (E?)-7-(2-hydroxy-4-(hydroxymethyl)phenyl)-2-methyloct-6-enoic acid (1) based on 1-D NMR, 2-D NMR and HR-ESI data.     

Two new chroman derivations from the endophytic Penicillium sp. DCS523

Strain DCS523 was isolated from the branch tissue of Daphniphyllum longeracemosum and determined to be a Penicillium sp. according to the ITS sequence analysis. The extracts from the PDA solid fermentation media of Penicillium sp. DCS523 were purified to give two new chroman derivatives as well as six known compounds. Based on their spectral data the new compounds were identified as (Z)-6-acetyl- 3-(1,2-dihydroxypropylidene)-5-hydroxy-8-methylchroman-2-one and 6-acetyl-2α,5- dihydroxy-2-(2-hydroxypropyl)- 3α,8-dimethylchroman, respectively.     

Reinvestigation of absolute stereostructure of (-)-rosiridol: structures of monoterpene glycosides, rosiridin, rosiridosides A, B, and C, from Rhodiola sachalinensis

Three new (-)-rosiridol glycosides, rosiridosides A, B, and C, were isolated from the roots of Rhodiola sachalinensis together with rosiridin [(-)-rosiridol 1-O-beta-D-glucopyranoside]. In the course of the structure elucidation of those new glycosides, the absolute configuration of the 4-position in (-)-rosiridol was reinvestigated. On the basis of the application of the modified Mosher's method for (-)- and (+)-rosiridol derivatives, the absolute configuration of the 4-position in (-)-rosiridol should be revised to be S orientation from the recently assigned R form, so that the absolute stereostructures of rosiridosides A, B, and C and rosiridin were determined.     

New aliphatic alcohol and (Z)-4-coumaric acid glycosides from Acanthus ilicifolius

From the aerial parts of Acanthus ilicifolius, a new aliphatic alcohol glycoside (ilicifolioside C) and two new (Z)-4-coumaric acid glycosides, (Z)-4-coumaric acid 4-O-beta-D-glucopyranoside and (Z)-4-coumaric acid 4-O-beta-D-apiofuranosyl-(1"-->2')-O-beta-D-glucopyranoside were isolated. The structural elucidations were based on the analyses of spectroscopic data. Z-Form 4-coumaric acid glycosides were first isolated from plant.     

Alkaloids from Papaver nudicaule L

A new promorphinane alkaloid (-)-8,14-dihydroflavinantine was isolated from the aerial parts of Papaver nudicaule L. (Papaveraceae) growing in Mongolia. Six known isoquinoline alkaloids (+)-amuronine, pseudoprotopine, allocryptopine, (-)-dihydroamuronine, (-)-amurensinine N-oxide A and (-)-amurensinine N-oxide B were isolated, too. Pseudoprotopine has been found for the first time in a plant of the family Papaveraceae. (-)-dihydroamuronine, (-)-amurensinine N-oxide A and (-)-amurensinine N-oxide B are new for the genus Papaver. All structures were established using spectral and physical data.     

Three new diarylheptanoids and their antioxidant property

Three new diarylheptanoids,i.e.,sodium(5S,2E)-1,7-bis(4-hydroxyphenyl)-1-hydroxy-2-hepten-5-sulfonate(1), sodium(5R,2E)-1,7-bis(4-hydroxyphenyl)-1-hydroxy-2-hepten-5-sulfonate (2) and 3,5-diacetoxy-1-(3-methoxy-4,5-dihydroxy- phenyl)-7-(4-hydroxy-3-methoxyphenyl)heptane (3) were isolated from the rhizomes of Zingiber officinale.The structures of the new compounds were elucidated on the basis of spectroscopic methods.The antioxidant activities of 3 were assayed by in vitro models involving DPPH free radicals and superoxide anion radicals.     

Pentacyclic triterpenoids from leaves of Excoecaria agallocha

A new oleanane-type triterpenoid (1) and five known pentacyclic triterpenoids (2-6) were isolated from the leaves of Excoecaria agallocha. Their structures were elucidated by spectroscopic analyses. The new compound was characterized as 3beta-[(2E,4E)-5-oxo-decadienoyloxy]-olean-12-ene (1). Compounds 1-6 were found inactive in vitro against several human cancer cell lines.     

Two neolignan glucosides and antihistamine release activities from Bidens parviflora WILLD

Two new neolignan glucosides, bidenlignasides A (1) and B (2), were isolated from the whole plant of Bidens parviflora WILLD. The structures of the two new compounds 1 and 2 established to be 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-3-[5E-(3-hydroxypropenyl)-3-methoxy-2-O-beta-D-glucosyl)phenyl] propan-1-one and 3-{3-[1,3-dihydroxy-3-(4-hydroxy-3-methoxyphenyl)propyl]-4-hydroxy-5-methoxyphenyl}-allyl-O-beta-D-glucuside, respectively, on the basis of spectral and chemical evidence. Compounds 1 and 2 were found to inhibit histamine release from peritoneal exudate mast cells induced by antigen-antibody reaction.     

Synthesis of (-)-arctigenin derivatives and their anticancer activity

The natural dibenzylbutyrolactone type lignanolide (-)-arctigenin, which was prepared from fructus arctii, showed obvious anticancer activity. The synthesis of four new (-)-arctigenin derivatives and their anticancer bioactivities were examined. The structures of the four new synthetic derivatives were elucidated.     

Two New Steroidal Saponins from Diuranthera inarticulata

There are only three species in the genus Diuranthera (Liliaceae), which is endemic in the southwest of China1. Four steroidal saponins, diuranthosides A-C and chloromalo-side A were isolated from the fresh roots of D. major. This paper deals with the structure elucidation of two new steroidal saponins, diuranthosides D and E, which were isolated from the methanolic extract of whole plant of D. inarticulata Wang et K. Y. Lang.Diuranthoside D (1), [(]-38 (c 0.08, pyridine), afforded galac…     

Medicinal flowers. VI. Absolute stereostructures of two new flavanone glycosides and a phenylbutanoid glycoside from the flowers of Chrysanthemum indicum L.: their inhibitory activities for rat lens aldose reductase

Two new flavanone glycosides, (2S)- and (2R)-eriodictyol 7-O-beta-D-glucopyranosiduronic acids, and a new phenylbutanoid glycoside, (2S, 3S)-1-phenyl-2,3-butanediol 3-O-beta-D-glucopyranoside, were isolated from the flowers of Chrysanthemum indicum L. cultivated in China together with eight flavonoids. The absolute stereostructures of the new compounds were determined on the basis of chemical and physicochemical evidence. Both of the new flavanone glycosides were found to show inhibitory activity for rat lens aldose reductase.     

Four new steroid constituents from the waste residue of fibre separation from Agave americana leaves

Three new steroidal saponins, named agamenosides H-J (1-3), and a new cholestane steroid agavegenin D (4) were isolated from the waste residue of fibre separation from Agave americana leaves, together with six known steroids. Structures of the new compounds 1-4 were deduced to be (22S,23S,24R,25S)-24-[(beta-D-glucopyranosyl)oxy]-5alpha-spirostane-3beta,6alpha,23-triol 6-O-beta-D-glucopyranoside (1), (22S,23S,24R,25S)-5alpha-spirostane-3beta,23,24-triol 24-O-beta-D-glucopyranoside (2), (22S,23S,25R,26S)-23,26-epoxy-5alpha-furostane-3beta,22,26-triol 26-O-beta-D-glucopyranoside (3), and (22S,25S)-5alpha-cholestane-3beta,16beta,22,26-tetrol (4), respectively, by means of spectroscopic analysis, including extensive 1D and 2D NMR data, and the results of hydrolytic cleavage.