Six pairs of phenylpropanoid enantiomers from Cinnamomum mollifolium.

Six pairs of undescribed phenylglycerol benzoate enantiomers, (±)-mollifolines A-F, which can also be categorized into three two-pairs of epimers, were isolated from Cinnamomum mollifolium H. W. Li (Lauraceae). The relative configurations (threo or erythro) of the epimers were determined by conformational searching of the lowest energy conformers and analyses of the relationship between the dihedral angle of H-7'─C-7'─C-8'─H-8' and the 3JH-7', H-8' coupling constant according to the Karplus equation. Furthermore, intramolecular hydrogen bonds were proved to play an important role in stabilizing the lowest conformations by using reduced density gradient (RDG) method for noncovalent interactions. Chiral resolutions of these enantiomer pairs were accomplished by immobilized polysaccharide derivative-based chiral HPLC columns. Absolute configurations of the 12 optically pure isomers were finally determined by quantum chemical time-dependent density functional theory (TDDFT) calculations of their electronic circular dichroism (ECD) spectra.

Two Novel Flavonoids and Cytotoxicity Evaluation from Cryptocarya yunnanensis.

Two new flavonoids, cryunchalcone (1) and cryptoyunnanone I (2), were isolated from the leaves and twigs of Cryptocarya yunnanensis. Their structures were elucidated by the detailed spectroscopic data analysis and electronic circular dichroism (ECD) calculations. Cryunchalcone (1) is a biflavonoid constructed by a dihydrochalcone coupled with a chalcone through an unprecedented C-2''-C-6 linkage. Cryptoyunnanone I (2) is a unique complex flavanone bearing a phenylpropanoid moiety.

Complex Flavanones from Cryptocarya metcalfiana and Structural Revision of Oboflavanone A.

Nine new complex flavanones, cryptometcones A-I (1-9), along with four known analogues, were isolated from Cryptocarya metcalfiana. The structures of 1-9 including their absolute configurations were elucidated by spectroscopic data analysis and electronic circular dichroism (ECD) calculations. In addition, the structure of oboflavanone A was revised, while the absolute configurations of oboflavanone B, cryptoflavanone C, and cryptoflavanone D were determined, according to their spectroscopic data. Compounds 3-5, 8, and 9 exhibited cytotoxicity against the HCT-116 cancer cell line.

Geranyl phenyl ethers from Illicium micranthum and their anti-HBV activity.

Fourteen new geranyl phenyl ethers (1-14) along with three known compounds (15-17) were isolated from Illicium micranthum, and their structures were elucidated by comprehensive spectroscopic methods. Illimicranins A-H (1-8) were characterized as geranyl vanillin ethers, while 9 and 10 were dimethyl acetal derivatives. Illimicranins I and J (11 and 12) were rare geranyl isoeugenol ethers. Illimicranins K and L (13 and 14) represented the first example of geranyl guaiacylacetone ether and geranyl zingerone ether, respectively. Compounds 1, 2 and 15 exhibited anti-HBV (hepatitis B virus) activity against HBsAg (hepatitis B surface antigen) and HBeAg (hepatitis B e antigen) secretion, and HBV DNA replication.

Cytotoxic α-pyrone derivatives from Cryptocarya yunnanensis.

Five new α-pyrone derivatives, cryptoyunnanes A - E (1 - 5), together with four known analogues, were isolated from the leaves and twigs of Cryptocarya yunnanensis. Their structures including absolute configurations were elucidated by extensive spectroscopic data and electronic circular dichroism (ECD) analyses. Compounds 4 and 6 showed significant cytotoxicity against A549, HCT-116, MDA-MB-231, PC-3 and HeLa with IC50 values from 2.25 to 8.97 µM. Compounds 1, 2 and 7 also displayed good cytotoxicity against HCT-116, MDA-MB-231 and PC-3 with IC50 values from 1.26 to 8.32 µM. This is the first time to report the isolation and bioactivity evaluation of chemical constituents from C. yunnanensis.

Neolignans and Sesquiterpenoid from Piper yunnanense.

Two biphenyl-type neolignans with a rare dibenzofuran skeleton, including a new one piyunneolignan A (1) and a known one piperneolignan D (2), together with a new sesquiterpenoid piyunin A (3), were isolated from the leaves and twigs of Piper yunnanense. Their structures were established on the basis of comprehensive spectroscopic data analysis and electronic circular dichroism (ECD) calculation. Piyunneolignan A (1) featured a rare C-2-C-2'/C-3-O-C-3' linkage. Compounds 1-3 were evaluated for their antimicrobial and cytotoxic activities against a panel of bacteria, fungi, and human cancer cell lines, respectively.

Cryptoyunnanones A-H, Complex Flavanones from Cryptocarya yunnanensis.

Eight new complex flavanones with a novel linkage, cryptoyunnanones A-H (1-8), together with four known α-pyrones, were isolated from the leaves and twigs of Cryptocarya yunnanensis. The structures of 1-8 including their absolute configurations were characterized by spectroscopic data analysis and single-crystal X-ray crystallography. Plausible biosynthetic pathways for the formation of compounds 1-8 were proposed. Compounds 1-4 exhibited cytotoxicity against HCT-116, MDA-MB-231, and PC-3 cancer cells with IC50 values from 6.4 to 9.1 µM.

Iridoid Constituents of Viburnum brachybotryum.

Eleven new iridoids, brachybones A-K (1-11), were isolated from the twigs of Viburnum brachybotryum. Their structures including absolute configurations were determined by spectroscopic data analysis and from the electronic circular dichroism (ECD) spectra. All of the compounds 1-11 possess one or two acetoxysenecioate substituents. Furthermore, compounds 5-7 and 11 feature a Cl atom in the molecule, while compounds 9-11 exhibit a cagelike rigid skeleton through an unusual oxo bridge from C-3 to C-8 or C-10. The isolates were evaluated for cytotoxic activity against the HCT-116, A549, and Hela cell lines, and the results showed compounds 10 and 11 to be active against HCT-116 cells.

Lignans and Neolignans with Antioxidant and Human Cancer Cell Proliferation Inhibitory Activities from Cinnamomum bejolghota Confirm Its Functional Food Property.

In the aim to evaluate the functional food property of Cinnamomum bejolghota, seven new lignans and neolignans, bejolghotins A-G (1-4 and 9-11), along with 14 known ones (5-8 and 12-21), were isolated and their structures including absolute configurations were elucidated by extensive spectroscopic data and electronic circular dichroism (ECD) analyses. All of the isolates were tested for antioxidant and human cancer cell proliferation inhibitory activities. Twenty compounds showed comparable antioxidant activity to the positive controls, and three significantly inhibited the growth of three cancer cell lines HCT-116, A549, and MDA-MB-231 with IC50 values of 0.78-2.93 µM, which confirmed its health benefits.

Anti-hepatitis B virus activity of swertisin isolated from Iris tectorum Maxim.

ETHNOPHARMACOLOGICAL RELEVANCE: Iris tectorum Maxim (I. tectorum, Yuan Wei in Chinese) is a common and traditional Chinese medicinal herb that be used to treat liver-related diseases. However, the anti-HBV activity of I. tectorum and its isolates has not been systemically studied. AIM OF THE STUDY: To screen the active part of I. tectorum and systemically evaluate their anti-HBV activity. MATERIALS AND METHODS: In this study, a series of compounds from I. tectorum were evaluated for their ability to inhibit HBV replication. Swertisin showed a significant inhibitory function on HBV replication. Then, the suppression effect of different concentrations of swertisin in HBsAg, HBeAg and HBV DNA level in HepG2.2.15 cells and HBV-infected HepG2-NTCP cells were comprehensive evaluated, respectively. Moreover, the anti-HBV effects of swertisin were confirmed in HBV transgenic mice model. RESULTS: Among these compounds, swertisin strongly inhibited the HBsAg, HBeAg and HBV DNA level in a dose-dependent manner in HepG2.2.15 cells and HBV-infected HepG2-NTCP cells. Furthermore, swertisin showed a significant inhibition role on HBV replication in HBV transgenic mice model, the inhibition effect of which was enhanced when combined with ETV. CONCLUSIONS: We have identified that swertisin can inhibit HBeAg and HBsAg production, as well as HBV DNA in vitro and in vivo. This study show that we may found a novel compound isolated from traditional Chinese medicines with potent anti-HBV function.

(±)-Meliviticines A and B: Rearranged prenylated acetophenone derivatives from Melicope viticina and their antimicrobial activity.

Two new prenylated acetophenone derivatives racemates, meliviticines A (1) and B (2) with unprecedented rearranged skeletons, were isolated from Melicope viticina. Subsequent chiral resolution led to the separation of two pairs of enantiomers, (±)-meliviticines A (1a/1b) and (±)-meliviticines B (2a/2b). Their structures including absolute configurations were elucidated by extensive spectroscopic data, electronic circular dichroism analysis, and X-ray crystallography. A plausible biosynthetic pathway of 1 and 2, involving ring cleavage and rearrangement of the prenylated acetophenone backbone was proposed. All the isolates showed moderate antimicrobial activities with MIC values of 25-50 µg/mL against several bacterial and fungal strains.

Cytotoxic arylalkenyl α,ß-unsaturated δ-lactones from Cryptocarya brachythyrsa.

Three new arylalkenyl α,ß-unsaturated δ-lactones, cryptobrachytones A-C (1-3), together with one known analogue kurzilactone (4), were isolated from the leaves and twigs of Cryptocarya brachythyrsa. Their structures were elucidated based on extensive spectroscopic data and electronic circular dichroism (ECD) analysis. All the isolates were evaluated in vitro for anti-proliferative activity against a panel of five human cancer cell lines and one human normal cell, respectively, and the results showed 1, 2 and 4 possessing significant selective cytotoxicity toward the human cancer cell lines with IC50 values from 5.41 to 15.43 µM. This is the first study for C. brachythyrsa.

Two spiroketal derivatives with an unprecedented amino group and their cytotoxicity evaluation from the endophytic fungus Pestalotiopsis flavidula.

Two new spiroketal derivatives with an unprecedented amino group, 2'-aminodechloromaldoxin (1) and 2'-aminodechlorogeodoxin (2), along with one known analogue dechloromaldoxin (3), were isolated from the plant endophytic fungus Pestalotiopsis flavidula. Their structures were elucidated on the basis of extensive spectroscopic analysis. The purification was cytotoxicity-guided which indicated the extract, fractions and compounds were evaluated in vitro for anti-proliferative activity against a panel of human cancer cell lines. The results showed compounds 1 and 2 with moderate cytotoxicity while 3 was inactive, which suggested -NH2 group might play a very important role for their cytotoxicity. This is the first study for P. flavidula and the first time to report the spiroketal derivatives as alkaloids from the Pestalotiopsis genus.

Sesquiterpenoid Lactones in Tanacetum huronense Inhibit Human Glioblastoma Cell Proliferation.

Tanacetum huronense (Lake Huron tansy), which is native to the upper Midwest region of USA and Canada, was examined for the presence of anticancer compounds using an in vitro human tumor cell proliferation inhibition assay, with glioblastoma derived cell line U-87 MG. Bioassay-directed purification of the ethyl acetate extract of the aerial portion of this plant identified six active sesquiterpenoid lactones (1-6). Among these, compounds 5 and 6 are new structural analogs. One of the most abundant isolates, tanacin (4), exhibited the greatest inhibition with an IC50 value of 4.5 µg/mL.

Phenanthrenes in Chinese Yam Peel Exhibit Antiinflammatory Activity, as Shown by Strong in Vitro Cyclooxygenase Enzyme Inhibition.

Chinese yam (Dioscorea opposita), peeled or whole, is a popular food item that is considered to be healthy. Often, the yam is peeled before cooking. However, it is also consumed with peel. Therefore, in this study, the peel of this yam was extracted sequentially with n-hexane, ethyl acetate and methanol, and studied for its health-benefits, using in vitro bioassays. Bioactivity-guided purifications of extracts of the peel afforded phenanthrenes (1-4), as characterized- by spectroscopic methods. Phenanthrene I is a novel analogue. The extracts and isolates were tested for antiinflammatory activity using cyclooxygenase enzyme (COX- I and -2) inhibitory assays. All phenanthrenes isolated from the yam peel showed higher inhibition of COX enzymes than the over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs) aspirin, ibuprofen and naproxen.

New antiinflammatory sucrose esters in the natural sticky coating of tomatillo (Physalis philadelphica), an important culinary fruit.

Tomatillo is a popular culinary fruit. The sticky material on its surface, consumed as part of the fruit, has never been investigated. Chemical characterization of sticky material on tomatillo fruits yielded five new sucrose esters, as confirmed by spectroscopic methods. The solvent extract of the sticky material from the whole fresh fruit and pure isolates showed antiinflammatory activity as confirmed by in vitro cyclooxygenase enzymes inhibitory assays. Five sucrose esters isolated at 100 µg/mL (153.8, 138.8, 136.2, 141.6 and 138.8 µM, respectively) inhibited cyclooxygenase-1 and -2 enzymes by 50%. The cyclooxygenase enzyme inhibitory activity of extract and isolates at 100 µg/mL was similar to non-steroidal antiinflammatory drugs aspirin, ibuprofen and naproxen, used as positive controls in the assay at 108, 12 and 15 µg/mL (600, 60 and 60 µM), respectively.

Antioxidant and Antiinflammatory Compounds in Nutmeg (Myristicafragrans) Pericarp as Determined by in vitro Assays.

Nutmeg, Myristicafragrans, is known for its culinary and medicinal values. The nutmeg pericarp, abundant during the production of the seed, is also used in food and beverage preparations. In this study, the pericarp of M. fragrans was evaluated for its bioactive components using in vitro antioxidant and antiinflammatory assays. The hexane, ethyl acetate and methanolic extracts inhibited lipid peroxidation (LPO) by 82.5, 70.1 and 73.2%, and cyclooxygenase enzymes COX-1 by 44, 44 and 42% and COX-2 by 47, 41 and 36%, respectively, at 100 microg/mL. The bioassay-guided purifications of extracts yielded 20 compounds belonged to neolignans (0.13%), phenylpropanoids (0.28%), phenolic aldehyde (0.35%), triterpenoids (0.06%), triglycerides (0.20%), sugars (10.2%) and steroids (0.49%). Pure isolates 1-5 inhibited LPO by 70-99% and 3-12 inhibited COX-1 and -2 enzymes by 37-49%. This is the first report on the bioassay-guided characterization of constituents in nutmeg pericarp. Our results support the medicinal claims of nutmeg pericarp.

Evaluation of coriander spice as a functional food by using in vitro bioassays.

Coriander leaves and seeds are widely used as a condiment and spice. The use of roasted coriander seeds in food and beverage is very common. In this study, we investigated raw and roasted coriander seeds for their functional food quality using antioxidant, anti-inflammatory and human tumour cell proliferation inhibitory assays. The hexane and methanolic extracts of raw and roasted coriander seeds showed identical chromatographic and bioassay profiles. Chromatographic purification of the roasted seed extracts afforded tripetroselinin as the predominant component. Other isolates were petroselinic acid, 1,3-dipetroselinin, 2-C-methyl-d-erythritol, 2-C-methyl-d-erythritol 4-O-ß-d-glucopyranoside and linalool. Hexane and methanolic extracts of both raw and roasted seeds and pure isolates from them showed comparable antioxidant and anti-inflammatory activities to the positive controls used in the assays, and inhibited the growth of human tumour cells AGS (gastric carcinoma), DU-145 and LNCaP (prostate carcinoma), HCT-116 (colon carcinoma), MCF-7 (breast carcinoma) and NCI-H460 (lung carcinoma) by 4-34%, respectively.

Phragmalin-type limonoids with NF-κB inhibition from Chukrasia tabularis var. velutina.

Chemical investigation on Chukrasia tabularis var. velutina led to the identification of eight new phragmalin-type limonoids (1-8), as well as 20 known analogues. Compounds 1-4 are a rare class of C-15-acyl phragmalin-type limonoids, and particularly compounds 2-4 also possess a δ-lactone ring formed between C-16 and C-30. All the isolates were evaluated for inhibitory effects on NF-κB production, and four of which showed significant inhibitions.

Major constituents of Boswellia carteri resin exhibit cyclooxygenase enzyme inhibition and antiproliferative activity.

Aromatic gum from Boswellia carteri (olibanum oleogum) has long been used in Egyptian traditional medicine. Cyclooxygenase-1 (COX-1) enzyme inhibitory assay guided purification of the extracts of this resin resulted in five bioactive compounds, 3alpha-O-acetyl-8,24-dien-tirucallic acid (1), verticilla-4(20),7,11-triene (2), cembrene A (3), incensole acetate (4), and incensole (5). The pure isolates were investigated for their inhibitory effects on COX-1 and -2 enzymes and human tumor cell lines Hep-G2, MCF-7 and RAW 264.7. Compounds 1-5 inhibited COX-2 enzyme by 39.0, 32.7, 60.0, 46.3, and 49.8%, respectively. Furthermore, compound 2 showed an inhibitory concentration of 50% (IC50) at 9 microg/mL against Hep-G2 tumor cell line. This is the first report of COX-1 and -2 enzyme and tumor cell proliferation inhibitory effects of compounds 1 and 2.