Bisabolane sesquiterpenes from the roots of Ligularia cymbulifera

Eight new highly oxygenated bisabolane sesquiterpenes (1-8), of which one contains a chlorine atom, were obtained in a phytochemical investigation of the roots of Ligularia cymbulifera, and their structures were elucidated by interpretation of spectroscopic data. Their relative configurations were clarified by a detailed analysis of (1)H NMR coupling constants and by NOE experiments. Compounds 1-8 were evaluated for antimicrobial activity against three bacterial cultures and a yeast culture.     

黄亮橐吾的苯并呋喃类化合物

目的　研究黄亮橐吾根和根茎的化学成分。方法　利用硅胶、Sephadex L H- 2 0柱色谱分离等方法进行分离和纯化,根据化合物的理化常数和波谱数据鉴定其结构。结果　从黄亮橐吾的根和根茎中分离到8个化合物,分别鉴定为:泽兰素(euparin, )、6 -甲氧基泽兰素(6 - methoxy- euparin, )、2 -羟基- 4 ,5 -二甲氧基苯甲醛(4,5 -dimethoxy- 2 - hydroxybenzaldehyde, )、2 -乙酰- 5 ,6 -二甲氧基苯并呋喃(2 - acetyl- 5 ,6 - dimethyoxybenzofuran, )、对羟基苯乙酮(4- hydroxyacetophenone, )、2 - isopropenyl- 5 ,6 - dim ethoxy- 2 ,3- hydrocum aran( )、8β- hydroxy- 7(11) - erem ophilen- 12 ,8α- olide ( )、羽扇豆醇(lupeol, )。结论　8个化合物均为首次从黄亮橐吾中分离得到。主要成分为苯并呋喃类化合物,特别是化合物 和 是两个重要的成分,具有杀虫和昆虫拒食活性,这和黄亮橐吾民间用于驱虫有相关性。     

大叶紫珠的化学成分研究

目的：研究大叶紫珠的化学成分。方法：采用多种色谱方法,对大叶紫珠的95%乙醇提取物的乙酸乙酯部位进行分离纯化,根据波谱学数据鉴定化合物的结构。结果：得到6个化合物,分别为丁香树脂醇（1）、木栓醇（2）、α-波甾醇（3）、咖啡酸乙酯（4）、对羟基苯甲醛（5）、（-）-松脂素（6）。结论：化合物1～6均从该植物中首次分离得到。     

Iridoids from Rothmannia macrophylla.

A new iridoid glucoside with an ether linkage between C-3 and C-10 and a novel nonglycosidic iridoid with an ether linkage between C-3 and C-6 and a lactonic linkage at C-1, named macrophylloside (1) and macrophyllide (2), respectively, were isolated from the leaves of Rothmannia macrophylla, along with six known iridoids. Their structures were established by NMR and MS spectroscopies.     

New sesquiterpenes from Capsicum annuum

The ethyl acetate soluble fraction of a MeOH extract of the dried stems and roots of Capsicum annum gave 10 new sesquiterpenoids (1-10) and nine known compounds. The structures of the new compounds were elucidated on the basis of spectroscopic evidence. The isolated new compounds were evaluated for their cytotoxic activities.     

Daucane sesquiterpenes from Ferula hermonis

The roots of Ferula hermonis Boiss yielded two new daucane esters, 14-(4'-hydroxybenzoyloxy)dauc-4,8-diene (1) and 14-(4'-hydroxy-3'-methoxybenzoyloxy)dauc-4,8-diene (2), together with the four known sesquiterpenes jaeschkeanadiol p-hydroxybenzoate (3), jaeschkeanadiol benzoate (4), jaeschkeanadiol (5), and epoxyjaeschkeanadiol (6). The identities of the isolated compounds were ascertained primarily using NMR and MS data. Compounds 1 and 3 exhibited antimicrobial activity against Staphylococcus aureus with IC(50) 1.5 and 3.5 microg/mL, respectively, and against Methicillin-resistant S. aureus with IC(50) 2.0 and 4.0 microg/mL, respectively.     

Muurolane sesquiterpenes from illicium tsangii

A dichloromethane extract of Illicium tsangii has yielded five novel muurolane sesquiterpenes (1, 2, 6, 7, 9) and three new menthane monoterpenes (10-12) in addition to several known compounds. Biogenetic relationships among the sesquiterpenes are discussed.     

New sesquiterpenes from Pluchea arabica

Two new sesquiterpenes, godotol A (1) and godotol B (2), were isolated from Pluchea arabica. Their structures were determined by analysis of NMR data. The absolute configurations of 1 and 2 were established by Mosher ester methodology. The godotols displayed weak activity against bacteria and the brine shrimp larvae. They were also inactive in the DPPH antioxidant assay.     

Daucane sesquiterpenes from Ferula hermonis

The dried roots of Ferula hermonis yielded three new daucanes, (1R,4R)-4-hydroxydauca-7-ene-6-one (1), (1R,4R)-4-hydroxydauca-7-ene-6,9-dione (2), and (1R,3S,8S)-3-ethoxy-8-angeloyloxydauca-4-en-9-one (3), together with the three known sesquiterpenes, ferutinin, teferidin, and (+)-alpha-bisabolol. The structures of compounds 1-3 were elucidated on the basis of spectroscopic evidence. The effect of these compounds on the proliferation of estrogen-dependent MCF-7 cells was evaluated, and it was found that compounds 1 and 3 exhibited proliferative activity, whereas 2 showed an antiproliferative effect.     

Minor sesquiterpenes from Maytenus chubutensis

Four new minor dihydro-beta-agarofuran-skeleton sesquiterpenes, 9 beta-benzoyloxy-1 alpha,2 alpha,6 beta-triacetoxy-15-hydroxydihydro-beta- agarofuran [1], 9 beta-benzoyloxy-1 alpha,2 alpha,6 beta,15-tetracetoxydihydro-beta-agarofuran [6], 9 alpha-benzoyloxy-1 alpha,2 alpha,6 beta-triacetoxy- 8 alpha,15-dihydroxydihydro-beta-agarofuran [7], and 9 alpha-benzoyloxy-1 alpha,2 alpha,6 beta,8 alpha-tetracetoxy-15- hydroxydihydro-beta-agarofuran [8] were isolated from the aerial parts of Maytenus chubutensis and identified by spectroscopy and chemical reactions.     

Cytotoxic sesquiterpenes from Aplysia dactylomela

Three new chamigrenes, compound 1, acetyldeschloroelatol 2 (2-bromo-1,1,9-trimethyl-5-methylenespiro[5.5]undec-8-en-3-yl acetate), and acetylelatol 4 (2-bromo-8-chloro-1,1,9-trimethyl-5-methylenespiro[5.5]undec-8-en-3-yl acetate), and the known metabolites deschloroelatol 3, elatol 5, 8-acetylcaespitol 6, and caespitol 7 have been isolated from the sea hare Aplysia dactylomela. The structures of 1, 2, and 4 were determined on the basis of spectroscopic evidences. The in vitro cytotoxicity of six of these compounds against two cancer cell lines (HeLa and Hep-2) and nontumoral Vero cells was evaluated. The results support the hypothesis that the acetate derivatives decrease the toxicity of the corresponding alcohols in a strategy to store toxic metabolites acquired through the diet.     

New sesquiterpenes from Ferula sinaica

The CH2Cl2 extract of Ferula sinaica afforded twelve sesquiterpenes including three new daucanes, 14-hydroxyvaginatin, 4 beta, 8 beta, 9 alpha-trihydroxy-6 alpha-p-hydroxy-benzoyloxydaucane, and isolancerotriol.     

天山橐吾的化学成分研究

从天山橐吾全草中共分离鉴定了6个化合物,分别为:Aurantiamide benzoate(1),Aurantiamide acetate (2),二十八硬脂酸单甘油脂(3),β-谷甾醇(4),胡萝卜苷(5)和阿魏酸(6).其中化合物1和2为该属首次分离得到.     

New indole alkaloids from Alstonia macrophylla

Ten new indole alkaloids, alstomaline (1), 10,11-dimethoxynareline (2), alstohentine (3), alstomicine (4), 16-hydroxyalstonisine (5), 16-hydroxyalstonal (6), 16-hydroxy-N(4)-demethylalstophyllal oxindole (7), alstophyllal (8), 6-oxoalstophylline (9), and 6-oxoalstophyllal (10), in addition to 21 other known ones, were obtained from the leaf extract of the Malayan Alstonia macrophylla. The structures were determined using NMR and MS analysis.     

Three new sesquiterpenes from Croton arboreous

Three new sesquiterpenes, 5alpha,7alpha,10betaH-3-patchoulen-2-one (1), 5alpha,7alpha10betaH-4(14)-patchoulen-2alpha-ol (2), and 9alpha,10beta-dihydroxy-2beta,4beta-peroxy-1alpha,5beta,7alphaH-guaiane (3), were isolated from the aerial parts of Croton arboreous along with 14 known compounds. The structures of these compounds were determined on the bases of their spectroscopic data (IR, UV, OR, 1D and 2D NMR, and MS). The anti-inflammatory activity against ear edema in mice produced by 12-O-tetradecanoylphorbol-13-acetate (TPA) was evaluated for all the pure compounds and showed that compounds 4-7 are active.     

New anthracene derivatives from Coussarea macrophylla

Five new naturally occurring anthracene derivatives, 1,4,10-trimethoxyanthracene-2-carbaldehyde (1), (1,4,10-trimethoxy-2-anthracen-2-yl)methanol (2), 1,4,8,10-tetramethoxyanthracene-2-carbaldehyde (3), 1,4,10-trimethoxyanthracene-2-carboxylic acid (4), and 1,3-dimethoxy-2-methoxymethylanthraquinone (5), were isolated from Coussarea macrophylla along with three known compounds, 3-hydroxy-1-methoxy-2-methoxymethylanthraquinone (6), scopoletin, and 3-epi-pomolic acid. The structures of 1-5 were determined on the basis of analysis of their spectroscopic data and by total synthesis.     

Antihyperglycemic sesquiterpenes from Psacalium decompositum.

Psacalium decompositum was investigated for antihyperglycemic compounds using diabetic ob/ob mice as a model for type 2 diabetes. In vivo bioassay-guided fractionation of an aqueous extract from the roots of P. decompositum led to the isolation of two new eremophilanolides, 3-hydroxycacalolide (1a) and epi-3-hydroxycacalolide (1b). A 1:1 mixture of 1a/1b exhibited antihyperglycemic activity when tested at 1.09 mmol/kg in ob/ob mice. The known furanoeremophilanes, cacalone (2a) and epicacalone (2b), were also isolated from the aqueous extract and were inactive. The known furanoeremophilane, cacalol (3), was isolated from a CH2Cl2 extract of P. decompositum roots and possessed antihyperglycemic activity. The relative stereochemistry in 1a and 1b was assigned 3R,5S and 3S,5S, respectively, based on ROESY data, 3J H-H values, and molecular mechanics calculations. Complete 13C and 1H NMR chemical shifts were assigned for 1a, 1b, 2a, 2b, and 3, and several revisions in 13C NMR assignments for 2a and 3 were made. Results from the conformational analysis of 1a, 1b, 2a, and 2b indicate that each compound exists in one major conformation in solution with H3-12 in a pseudoaxial position.     

Male-specific sesquiterpenes from Phyllotreta flea beetles

Flea beetles in several genera are known to possess male-specific sesquiterpenes, at least some of which serve as aggregation pheromones that attract both sexes. In continuing research on the chemical ecology of Phyllotreta flea beetles, six new male-specific sesquiterpenes were identified, one from P. striolata (hydroxyketone 9) and five from P. pusilla (aldehydes 10-12 and 14 and alcohol 13); both species are crop pests. The minute amounts from beetles provided mass spectra and chromatographic data but were insufficient for complete structure determination. However, it was discovered that the new compounds could all be produced by applying organic reactions to previously identified flea beetle sesquiterpenes, and the resulting, larger amounts of material permitted definitive structure analysis by NMR. Molecular modeling was used in conjunction with NMR to define relative configurations of several newly created stereogenic centers. The absolute configurations of natural 9-14 were established by chiral gas chromatography/mass spectrometry. In electrophysiological tests (GC-EAD) conducted with P. striolata, compound 9 was detected with high sensitivity by the beetle antennae, which is consistent with a pheromonal function. The research opens new possibilities for using behavioral chemicals to monitor or manage these pest species.     

New eudesmane sesquiterpenes from Plectranthus cylindraceus

Three new eudesmane sesquiterpenes, plectranthone (1), desacetylplectranthone (2), isodeacetylplectranthone (3), and the three known flavonols pachypodol, casticin, and chrysosplenol D were isolated for the first time from the aerial parts of Plectranthus cylindraceus. Their structures have been established on the basis of spectral data. The structures and relative stereochemistries of 1 and 2 were confirmed by single-crystal X-ray analysis.     

大叶紫珠醇溶性成分的研究

目的对大叶紫珠的醇溶性成分进行研究。方法对大叶紫珠甲醇提取液再进行溶剂和柱分离纯化,根据EIMS和NMR波谱数据进行结构鉴定。结果从大叶紫珠正丁醇萃取物中分离鉴定了6个化合物,包括4个黄酮类化合物和2个酚酸类化合物,经波谱解析分别鉴定为槲皮素-7-O-芸香糖苷(1)、木犀草苷(2)、木犀草素-7-O-新橙皮糖苷(3)、异槲皮苷(4)、草木樨苷(5)、类叶升麻苷(6)。结论除化合物2和6之外,其他化合物均为首次从马鞭草科紫珠属植物大叶紫珠中分离得到。