Hung-Chun Yeh

Isolation of new esters from the stems of Cinnamomum reticulatum Hay

The stems of Cinnamomum reticulatum Hay (Lauraceae) were extracted with hexane and chloroform successively. A series of new esters, including a mixture of 4-hydroxy-3-methoxyphenethyl derivatives (1–5), along with two butanolides, isoobtusilactone A (6) and obtusilactone A (7), two amides, N-trans-feruloylmethoxytyramine (8) and N-cis-feruloyl-methoxytyramine (9), three benzenoids, p-hydroxybenzoic acid (10), syringic acid (11) and vanillic acid (12), one lignan, (+)-syringaresinol (13) and one steroid, β-sitostenone (14), were isolated. The structures of the new esters were elucidated by chemical and physical evidence.

A novel normonoterpenoid from the stems of Cinnamomum reticulatum Hay

Reticuone (1), a novel Cinnamomum normonoterpenoid, has been isolated from Cinnamomum reticulatum Hay (Lauraceae), and its structure was determined on the basis of spectroscopic analysis.

Chemical constituents from the leaves of Cinnamomum reticulatum

Reticuol, a novel Cinnamomum sesquiterpenoid, has been isolated from Cinnamomum reticulatum Hay (Lauraceae), together with eight known compounds, p-hydroxybenzoic acid, isoanwulignan, 2,6-dimethyl1,7-octadiene-3,6-diol, a-tocopheryl quinone, kaempferol-3-O-(2″,4″-di-E-p-coumaroyl)-α-L-rhamnopyranoside, kaempferol-3-O-(3″,4″-di-E-p-coumaroyl)-α-L-rhamnopyranoside, pheophorbide a, and aristophyll C. The structure of reticuol was determined on the basis of spectroscopic analysis.

A new amide from the stems of Cinnamomum reticulatum Hay

Cinnaretamine, a new amide, has been isolated from Cinnamomum reticulatum Hay (Lauraceae), together with six known compounds, N-trans-feruloylmethoxytyramine, N-cis-feruloylmethoxytyramine, (+)-syringaresinol, p-hydroxybenzoic acid, syringic acid and vanillic acid. The structure of cinnaretamine was determined on the basis of spectroscopic analysis.

(S*)-2,7,8-Trihydroxychroman-4-one

Reticumanone (1), a new chromanone, isolated from the leaves of Cinnamomum reticulatum Hay (Lauraceae), has been characterized as (S*)-2,7,8-trihydroxychroman-4-one, by means of spectroscopic methods.

A new butanolide from the leaves of Cinnamomum reticulatum

A new butanolide, isoreticulide ((4R,3E)-4-hydroxy-5-methylene-3-octadecylidenedihydrofuran-2-one) (1), along with nine compounds including one sesquiterpenoid, (3-methoxy-5H-9,11dioxabenzo[3,4]cyclohepta[1,2-f])inden-7-yl)-methanol (2); six benzenoids, p-hydroxybenzoic acid (3), p-hydroxybenzaldehyde (4), protocatechuic acid (5), ferulic acid (6), trans-methyl p-coumarate (7), and p-dihydrocoumaric acid (8), and two amides, N-trans-feruloyltyramine (9) and dihydroferuloyltyramine (10), were isolated from the leaves of Cinnamomum reticulatum Hayata (Lauraceae). These compounds were characterized and identified by physical and spectral evidence.

Secondary Metabolites of the Leaves of Cinnamomum kanehirai

Cinnamomum kanehirai Hayata (Lauraceae), a unique and native tree of Taiwan, is the major host for the medicinal fungus Antrodia cinnamomea, which exhibits anti-cancer activity [1]. In the course of screening for biologically and chemically novel agents from Formosan Lauraceous plants [2], C. kanehirai Hayata was chosen for further phytochemical investigation. It grows in the mountains at an altitude of about 450–2000 m around the broad-leaved forests in Taiwan. In traditional Chinese medicine, it is claimed to be beneficial to clear the lungs, dispel apathy, and calm nervous depression. People hew this tree to harvest or cultivate its infected fungus, A. cinnamomea, for treatment of disease in folk medicine. Growing evidences show that extracts, fermented products, or compounds isolated from A. cinnamomea possess growth inhibitory activity against various types of cancers [1]. Other than its infected fungus, A. cinnamomea, little is known about this plant. The leaves of this plant are also being studied and published for the first time. The MeOH extract of its leaves was subjected to solvent partitioning and chromatographic separation to afford eight pure substances. The leaves of Cinnamomum kanehirai Hayata were collected from Kaohsiung City, Taiwan in June 2011. Plant material was identified by Dr. Fu-Yuan Lu (Department of Forestry and Natural Resources, College of Agriculture, National Chiayi University). A voucher specimen (Cinnamo. 10) was deposited in the School of Medical and Health Sciences, Fooyin University, Kaohsiung, Taiwan. The air-dried leaves of C. kanehirai (0.4 kg) were extracted with MeOH (2 L 5) at room temperature, and a MeOH extract (24.1 g) was obtained upon concentration under reduced pressure. The residue was placed on a silica gel column and eluted with CH2Cl2 gradually enriched with MeOH to afford three fractions. Fraction 1 (2.23 g) eluted with n-hexane–acetone (40:1) was further purified by silica gel column chromatography using the same solvent system to obtain coumarin [2] (4 mg), isoscopoletin [3] (2 mg), and scopoletin [4] (8 mg). Fraction 2 (4.67 g) eluted with n-hexane– acetone (30:1) was further separated using silica gel column chromatography and purified by preparative TLC (thin-layer chromatography) to yield -sitostenone [5] (16 mg) and -sitosterol [5] (75 mg). Fraction 3 (2.13 g) was purified by silica gel chromatography (CH2Cl2–MeOH, 25:1) to give (+)-yangambin [6] (2 mg), (+)-syringaresinol [7] (9 mg), and (+)-sesamin [8] (13 mg). These compounds were obtained and characterized by comparison of their physical and spectral data with values obtained in the literature. All of these compounds were found for the first time from this plant.

A New Dimeric Ionone from the Unripe Fruits of Capsicum annuum var. conoides

Red pepper, Capsicum annuum (Solanaceae), is used as a spice all over the world. Red pepper is studied actively because its pungent principal component, capsaicin, has a dietary effect, analgesic activity, and antioxidant activity [1]. The pungent principal component of red peppers is a group of acid amides of vanillylamine and C8 to C13 fatty acids, which are known generally as capsaicin [2]. More than 16 other capsaicinoids have been found as minor components [3]. Numerous studies have been done on the red pepper fruit, but there are few studies on stems [2–4]. Previously, we isolated 19 compounds, including ten amides, four steroids, and six benzenoids from the stems of this plant [5]. We also isolated 17 compounds, including three chlorophylls, six steroids, one ionone, and seven benzenoids from the unripe fruits of this plant [6]. To further understand the chemotaxonomy and to continue searching for biologically and chemically novel agents from Solanaceous plants, the unripe fruits of C. annuum L. var. conoides (Mill.) Irish were chosen for further phytochemical investigation. In this paper, we report the isolation and structural elucidation of this new dimeric ionone. Conoidol (1) was obtained as a white amorphous powder from CHCl3. Its molecular formula was deduced as C27H36O5 by HR-ESI-MS (m/z 463.2458 ([M + Na]+; calcd 463.2460)). The UV spectrum of conoidol contained absorption bands typical of the -ionone derivatives [7]. The IR spectrum of conoidol showed characteristic absorption bands due to the presence of hydroxyl (3400 cm–1) and carbonyl (1665 cm–1) groups. The 1H NMR spectrum of conoidol contained two ethylenic protons indicated by two doublets each for 1H at 6.83 (2H, d, J = 16.0 Hz) and 6.47 (2H, d, J = 16.0 Hz), and their spin coupling pattern indicates the presence of one trans-disubstituted ethylene moiety in the molecule. It also represented one hydroxy proton at 5.70 (1H, s), three methine protons at 5.96 (2H, s) and 4.34 (1H, br.s), and four methylene protons at 2.34 (2H, d, J = 17.0 Hz) and 2.50 (2H, d, J = 17.0 Hz). The compound also illustrated four characteristic singlets for 24 protons at 2.31 (6H, s), 1.88 (6H, br.d, J = 1.0 Hz), 1.11 (6H, s), and 1.03 (6H, s). The 13C NMR and DEPT experiments of 1 showed 14 resonance lines consisting of four methyls, one methylene, four methines, and five quaternary carbons. The structure of conoidol was also confirmed by 2D NMR experiments. A COSY correlation was observed between H-1 and H-2 , and between H-1 and H-2 . The HETCOR experiment showed that the carbon signals at 49.3 for C-6 (C-6 ), 127.2 for C-2 (C-2 ), 130.6 for C-2 (C-2 ), and 145.5 for C-1 (C-1 ) were correlated to the proton signals at 2.34 and 2.50 for H-6 (H-6 ), 5.96 for H-2 (H-2 ), 6.47 for H-2 (H-2 ), and 6.83 for H-1 (H-1 ), respectively. Thus, 1 is a dimer of (S)-dehydrovomifoliol [8], which was further confirmed by NOESY and HMBC experiments.

Chemical Constituents of the Flowers of Michelia alba

Michelaine (1), (–)-anonaine, (–)-norushinsunine, (–)-ushinsunine, (–)-N-acetylanonaine, liriodenine, atherospermidine, (+)-syringaresinol, N-trans-feruloyltyramine, p-hydroxybenzaldehyde, vanillin, vanillic acid, syringic acid, coniferyl aldehyde, syringin, scopoletin, 4-acetonyl-3,5-dimethoxy-p-quinol, β-sitostenone, and stigmasta-4,22-dien-3-one were isolated from the flowers of Michelia alba (Magnoliaceae). Among them, michelaine (1) is a new 4,5-dioxoaporphine compound. The structures of these compounds were characterized and identified by spectral analyses.

Secondary Metabolites from the Stems of Ilex cornuta

Ilex (Aquifoliaceae) species are distributed widely in the People s Republic of China, and some are used extensively in folk medicine. For example, I. rotunda is an antipyretic and antidote and is used for the treatment of the common cold, tonsillitis, and stomach and intestinal ulcers. I. pubescens is used for the treatment of coronary disease, myocardial infarction, dysentery, and erysipelas. I. cornuta and I. latifolia are used for the treatment of headache, toothache, bloodshot eyes, and tinnitus [1]. Previous studies on the Ilex genus have led to the isolation of triterpenes, triterpene glycosides [2], hemiterpene glycosides [3], phenolic compounds [4], and flavonoids [5]. In the present study on the chemical components of the stems of I. cornuta, five compounds were isolated. A methanolic extract of the stems of I. cornuta was concentrated to obtain a residue, and it was partitioned between CH2Cl2 and H2O. The aqueous layer was extracted with n-BuOH. The n-BuOH layer was concentrated and subjected to chromatography. As a result, five compounds, including a dihydroberberine alkaloid, oxyberberine (1) [6], and four protoberberine alkaloids, berberine (2) [7], palmatine (3) [8], jatrorrhizine (4) [9], and columbamine (5) [10], were isolated. All of these compounds were isolated for the first time from this source. The stems of I. cornuta were collected from Kaohsiung, Taiwan, October 2006. Plant material was identified by Dr. Fu-Yuan Lu (Department of Forestry and Natural Resources, College of Agriculture, National Chiayi University). A voucher specimen was deposited in the School of Medical and Health Sciences, Fooyin University, Kaohsiung, Taiwan. The air-dried stems of I. cornuta (2.3 kg) were extracted with MeOH (10 L 5) at room temperature, and a MeOH extract was obtained upon concentration under reduced pressure. The combined MeOH extracts were evaporated and partitioned to yield CH2Cl2 and aqueous extracts. The aqueous extracts were evaporated and extracted with n-BuOH to give an n-BuOH layer and an aqueous layer. The n-BuOH layer (72.8 g) was chromatographed over silica gel (500 g, 70–230 mesh) using CH2Cl2–MeOH mixtures as the eluent to produce five fractions. Part of fraction 1 (16.7 g) was subjected to silica gel chromatography, eluted with n-hexane–CH2Cl2 (1:1), and enriched gradually with CH2Cl2, to furnish five fractions (1-1–1-5). Fraction 1-4 (1.3 g) was further purified on a silica gel column using n-hexane–CH2Cl2 mixtures to obtain oxyberberine (1) (7 mg). Part of fraction 2 (12.4 g) was subjected to silica gel chromatography, eluted with CH2Cl2–MeOH (8:1), and enriched with MeOH to furnish five further fractions (2-1–2-5). Fraction 2-2 (3.2 g) was further purified on a silica gel column using CH2Cl2–MeOH mixtures to obtain berberine (2) (24.9 mg). Part of fraction 3 (17.4 g) was subjected to silica gel chromatography, eluted with CH2Cl2–MeOH (7:1), and enriched with MeOH to furnish five further fractions (3-1–3-5). Fraction 3-4 (4.5 g) was further purified on a silica gel column using CH2Cl2–MeOH mixtures to obtain palmatine (3) (31.2 mg). Part of fraction 4 (12.9 g) was subjected to silica gel chromatography, eluted with CH2Cl2–MeOH (7:1), and enriched with MeOH to furnish four further fractions (4-1–4-4). Fraction 4-2 (3.3 g) was further purified on a silica gel column using CH2Cl2–MeOH mixtures to obtain jatrorrhizine (4) (3 mg). Part of fraction 5 (22.3 g) was subjected to silica gel chromatography, eluted with CH2Cl2–MeOH (6:1), and enriched with MeOH to furnish three further fractions (5-1–5-3). Fraction 5-2 (2.3 g) was further purified on a silica gel column using CH2Cl2–MeOH mixtures to obtain columbamine (5) (13 mg).