A new diarylheptanoid from the rhizomes of Zingiber mekongense.

A new diarylheptanoid, (3S,5S)-3,5-diacetoxy-1,7-bis(3,4,5-trimethoxyphenyl)heptane (1), together with the known docosyl trans-ferulate (2), (1S,2S,4S)-p-menthan-1,2,4-triol (3), 5αH-eudesmane-4α,11-diol (4), 5αH-eudesmane-4ß,11-diol (5), 4α,10ß-dihydroxy-1ßH,5αH-guaia-6-ene (guaianediol) (6), (+)-galanolactone (7), (E)-labda-8(17),12(13)-dien-15,16-olide (8), labda-8(17),13(14)-dien-15,16-olide (9), 3,5-dihydroxy-7,4'-dimethoxyflavone (10) and 3,5,3'-trihydroxy-7,4'-dimethoxyflavone (11) were isolated from the rhizomes of Zingiber mekongense. Their structures were determined by spectroscopic methods. The stereochemistry of 1 was proved through chemical conversion. Compounds 1, 4-7 and 9-11 exhibited anti-HIV-1 activities in the anti-syncytium assay using (∆Tat/rev)MC99 virus and 1A2 cell line system, while only compounds 7 and 11 were found active in the HIV-1 reverse transcriptase assay.

Three new antibacterial active diarylheptanoids from Alpinia officinarum.

Three new diarylheptanoids, together with ten known ones, were isolated from the ethanol extract from the rhizomes of Alpinia officinarum Hance. The structural identification of these compounds was mainly achieved by spectroscopic methods. The new compounds were elucidated as 7-(4", 5"-dihydroxy-3"-methoxyphenyl)-1-phenyl -4-heptene-3-one (1), 1, 7-diphenyl-5-heptene-3-one (2) and 4-phenethyl-1, 7-diphenyl -1-heptene-3, 5-dione (3), respectively. All of the compounds showed antibacterial activity against Helicobactor pylori. Especially, the three new compounds showed strong antibacterial activity against Hp-Sydney strain 1 with the MIC values of 9-12 µg/mL, and against Hp-F44 with the MIC values of 25-30 µg/mL.

Cytotoxic alkyl benzoquinones and alkyl phenols from Ardisia virens.

Bioassay-guided fractionation of roots and stems of Ardisia virens Kurz (Myrsinaceae) led to isolation of fourteen compounds, (2'R)-6-(2'-acetoxypentadecyl)-5-hydroxy-2-methoxy-1,4-benzoquinone (1), (2'R)-6-(2'-acetoxytridecyl)-5-hydroxy-2-methoxy-1,4-benzoquinone (2), (2'R)-6-(2'-acetoxytridecyl)-2-methoxy-1,4-dihydroxybenzene (3), (2'R)-6-(2'-acetoxytridecyl)-5-formyl-2-methoxy-1,4-dihydroxybenzene (4), 1-(3,5-dihydroxyphenyl)nonan-1-one (5), 1-(3-hydroxy-5-methoxyphenyl)pentan-1-one (6), (2'S)-3-hydroxy-5-methoxyphenyl-2'-tridecanol (7), (2'S)-3-hydroxy-5-methoxyphenyl-2'-pentadecanol (8), (2'S)-5-acetoxy-3-hydroxyphenyl-2'-tetradecanol (9), 1-acetoxy-2-methoxy-6-pentadecyl-4-hydroxybenzene (10), 1-acetoxy-2-methoxy-6-tridecyl-4-hydroxybenzene (11), (2'R)-1-acetoxy-6-(2'-acetoxy-tridecyl)-2-methoxy-4-hydroxybenzene (12), (2'R)-1-acetoxy-6-(2'-acetoxypentadecyl)-2-methoxy-4-hydroxybenzene (13), and 1-acetoxy-6-(2'-ketopentadecyl)-2-methoxy-4-hydroxylbenzene (14), together with thirty-four other known compounds, of which three, 1-(3,5-dihydroxyphenyl)pentan-1-one (15), 1-(3,5-dihydroxyphenyl)heptan-1-one (16), and 1-(3,5-dihydroxyphenyl)pentadecan-1-one (17), were isolated for the first time from a natural source. Their structures were elucidated by analyses of spectroscopic data. Seven cytotoxic constituents were found to be 3, 10-12, ardisianone (18), cornudentanone (19), and ardisianol (31) with cytotoxic properties (IC(50) values < or =4 microg/mL) against MCF-7, NCI-H460 and SF-268 cancer cell lines in vitro.

Semipreparative-scale gas-chromatographic separation of filbertone enantiomers.

The enantioselectivity of heptakis(2,3-di-O-acetyl-6-O-tert-butyldimethylsilyl-beta-CD) toward racemic filbertone (E-5-methyl-hep-2-en-4-one) was studied by performing the chiral separation on a capillary column, a thick-film wide-bore column and a semipreparative column. The semipreparative enantioseparation of filbertone was achieved at 80 degrees C by using a packed column providing (R)- and (S)-enantiomers of filbertone with ee 90 and 96%, respectively. The isolated enantiomers (approximately 250 microg each, ee = 90-96%) may be used for studies on the relationship of chirality and biological activity by olfactory screening and toxicological studies.

Determination of diarylheptanoids from Alpinia officinarum (Lesser Galangal) by HPLC with photodiode array and electrochemical detection.

Normal-phase column chromatography followed by semi-preparative reversed-phase HPLC has been used to isolate, from the rhizomes of Alpinia officinarum, five diarylheptanoids identified as 5-hydroxy-7-(4"-hydroxy-3"-methoxyphenyl)-1-phenyl-3-heptanone, 5-methoxy-7-(4"-hydroxy-3"-methoxyphenyl)-1-phenyl-3-heptanone, 7-(4"-hydroxyphenyl)-1-phenylhept-4-en-3-one, 7-(4"-hydroxy-3"-methoxyphenyl)-1-phenyl-hept-4-en-3-one, 1,7-diphenylhept-4-en-3-one. The levels of these five diarylheptanoids in root material were determined quantitatively by HPLC with UV detection and the assay methods so developed were simple, rapid and accurate. Four of the diarylheptanoids could also be detected by HPLC with electrochemical detection (ECD) in the oxidative mode, and ECD was found to have a higher sensitivity than photodiode array detection.

5-Hydroxy-7-(4'-hydroxy-3'-methoxyphenyl)-1-phenyl-3-heptanone: a pancreatic lipase inhibitor isolated from Alpinia officinarum.

A pancreatic lipase inhibitor, 5-hydroxy-7-(4'-hydroxy-3'-methoxyphenyl)-1-phenyl-3-heptanone (HPH), from the rhizome of Alpinia officinarum (AO) was isolated and its antihyperlipidemic activity was measured. HPH inhibited a pancreatic lipase with an IC(50) value of 1.5 mg/ml (triolein as a substrate). HPH significantly lowered the serum TG level in corn oil feeding-induced triglyceridemic mice, and reduced serum triglyceride (TG) and cholesterol in Triton WR-1339-induced hyperlipidemic mice. However, HPH did not show hypolipidemic activity in high cholesterol diet-induced hyperlipidemic mice. Based on these findings, we propose that PL inhibitors may be effective as hypolipidemic agents.

Novel diarylheptanoids of Alpinia blepharocalyx.

The seeds of Alpinia blepharocalyx K. Schum. (Zingiberaceae) is used in Chinese traditional medicine for the treatment of stomach disorders. From the ether fraction of a 95% ethanolic extract, which showed hepatoprotective and antiproliferative activities, we isolated 16 novel diarylheptanoids bearing a chalcone or a flavanone moiety [calyxins A-H; epicalyxins B-D, G, and H; 6-hydroxycalyxin F; and blepharocalyxins A and B] together with seven known compounds, while the residual fraction of the ethanolic extract gave 32 novel diarylheptanoids namely, calyxins A, E-G, and I-M; epicalyxins B, F, I-K, and M; deoxycalyxin A; blepharocalyxins C-E; neocalyxins A and B; (3S,5S)- and (3S,5R)-3-hydroxy-1-(4-hydroxyphenyl)-5-methoxy-7-phenyl-6E-heptene, (3S,5S)- and (3S,5R)-3-hydroxy-1-(4-hydroxyphenyl)-5-ethoxy-7-phenyl-6E-heptene, (3S)-3-methoxy-1,7-bis(4-hydroxyphenyl)-6E-hepten-5-one, 1,7-bis(4-hydroxyphenyl)-hepta-4E,6E-dien-3-one, (3S,7R)-5,6-dehydro-1,7-bis(4-hydroxy-phenyl)-4"-de-O-methyl-centrolobine, (3S,5S,6S,7R)-5,6-dihydroxy-1,7-bis(4-hydroxyphenyl)-4"-de-O-me-thylcentrolobine, (3S,5R,6S,7R)- and (3S,5S,6R,7R)-5,6-dihydroxy-1,7-bis(4-hydroxyphenyl)-4"-de-O-methyl-centrolobine, 1,2- dihydro-bis(de-O-methyl)curcumin, and (3S,7S)-5,6-dehydro-4"-de-O-methylcentrolobine, and one known diarylheptanoid [(3S,5S)-3,5-dihydroxy-1,7-bis(4-hydroxyphenyl)heptane] together with 12 other known phenolic compounds. Moreover, in vitro NO inhibitory and antiproliferative activities of the isolated compounds were also tested and the active constituents identified.

New diarylheptanoids and diarylheptanoid glucosides from the rhizomes of Tacca chantrieri and their cytotoxic activity.

Two new diarylheptanoids (1, 2) and seven new diarylheptanoid glucosides (3-9) were isolated from the rhizomes of Tacca chantrieri. Their structures were determined by spectroscopic analysis, including 2D NMR data, and the results of hydrolytic cleavage. The absolute configurations of the 3,5-dihydroxyheptane moieties of the new diarylheptanoids were determined to be 3R and 5R by the application of the CD exciton chirality method to the corresponding 3,5-bis-p-bromobenzoyl derivatives. The cytotoxic activities of the isolated compounds and some derivatives against HL-60 human promyelocytic leukemia cells, HSC-2 human oral squamous carcinoma cells, and normal human gingival fibroblasts (HGF) are reported.

Diarylheptanoids with in vitro inducible nitric oxide synthesis inhibitory activity from Alnus hirsuta.

Four diarylheptanoids were isolated from the leaf of Alnus hirsuta (Betulaceae) and have been assessed for nitric oxide (NO) production inhibitory effects in vitro. Oregonin (1) and hirsutanonol (2) were found to be potent inducible nitric oxide synthase (iNOS) inhibitors. Compounds 1 and 2 showed inhibition of NO synthesis in dose-dependent manners by murine macrophage-like RAW 264.7 cells stimulated with interferon-gamma (IFN-gamma) plus lipopolysaccharide (LPS). Their 50% inhibitory concentrations (IC50) were 3.8 and 14.3 microM, respectively. The inhibitory effects of these compounds on NO synthesis were due to suppression of iNOS mRNA expression as determined by Northern blotting.

Cartorimine, a new cycloheptenone oxide derivative from Carthamus tinctorius.

Cartorimine (1), a new cycloheptenone oxide derivative, was isolated from Carthamus tinctorius, and its structure was established from spectral data interpretation and single-crystal X-ray analysis.

Non-phenolic linear diarylheptanoids from Curcuma xanthorrhiza: a novel type of topical anti-inflammatory agents: structure-activity relationship.

The topical anti-inflammatory activity of three non-phenolic linear 1,7-diarylheptanoids, previously isolated from a Thai medicinal plant, Curcuma xanthorrhiza (Zingiberaceae) and four new semi-synthetic derivatives of the naturally occurring compounds were assessed in the murine model of ethyl phenylpropiolate-induced ear edema. The naturally occurring compound 1E,3E,1,7-diphenylheptadien-5-one (6) exerted the most potent anti-inflammatory activity, with an ID50 value of similar magnitude to that of the reference drug oxyphenbutazone (67 vs. 46 micrograms/ear, respectively). None of the semi-synthetic diarylheptanoids was more active than 6. The chemical structures and pharmacological data of the natural and semi-synthetic derivatives identified a distinct structure-activity relationship. The degree of unsaturation in positions 1 and 3, and the nature of the oxygenated functional group in position 5 of the C7-chain were found to play significant roles in determining the observed in vivo activity. Based on these findings, the non-phenolic linear 1,7-diarylheptanoids-are proposed to represent a novel class of topical anti-inflammatory agents.

[Constituents of Acer nikoense and Myrica rubra. On diarylheptanoids].

The diarylheptanoid constituents of the titled plants and their close plants were reviewed. Many new diarylheptanoids and their glycosides named acerogenin and aceroside were isolated from the stem bark of Acer nikoense, A. griseum and A. triflorum. Myricanone, myricanol and its five new glycosides were isolated from the stem bark of Myrica rubra, and myricanone and galeon, from the stem of M. gale var. tomentosa. The structures of these compounds were determined on the basis of chemical and spectral evidence, and chemotaxonomy of the above plants was briefly discussed. In addition biosynthesis of acerogenin A, revision of the structure for isomyricanone derived from myricanone, and some biological activities of A. nikoense and M. rubra were described.

Inhibition of prostaglandin and leukotriene biosynthesis by gingerols and diarylheptanoids.

The rhizomes of Zingiber officinale (ginger) and Alpinia officinarum contain potent inhibitors against prostaglandin biosynthesizing enzyme (PG synthetase). Gingerols and diarylhepatanoids were identified as active compounds. Their possible mechanism of action which was deduced from the structures of active compounds indicated that the inhibitors would also be active against arachidonate 5-lipoxygenase, an enzyme of leukotriene (LT) biosynthesis. This was verified by testing their inhibitory effects on 5-lipoxygenase prepared from RBL-1 cells. A diarylheptanoid with catechol group was the most active compound against 5-lipoxygenase, while yakuchinone A was the most active against PG synthetase.