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1.
A new sesquiterpene of the caryophyllene series, fuscoatrol A (1), and known compounds, 11-epiterpestacin (2) and -nitropropionic acid (3), were isolated from the marine fungus Humicola fuscoatra (Traaen) KMM 4629 associated with the Kuril colonial ascidium. The structure of 1 was established on the basis of X-ray diffraction data and 2D NMR spectroscopy. The antimicrobial and cytotoxic activities of compounds 1–3 were studied.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2534–2537, November, 2004.  相似文献   
2.
Bioassay directed-fractionation led to the identification of litseaverticillols A-H (1-8) from the leaves and twigs of Litsea verticillata Hance. These new sesquiterpenes possess a unique skeleton that was recently designated as ‘litseane’. The structures of these compounds were determined by spectroscopic means including 1D and 2D NMR data. Structural configurations were determined by ROESY experiments. Mosher ester reactions and optical rotation measurements established the sesquiterpenes 1-8 as racemates. Isolates 1-8 inhibited HIV-1 replication in HOG.R5 cells with IC50 values ranging from 2 to 15 μg/ml (8-58 μM) while affecting the growth of HOG.R5 at concentrations 2-3-fold higher. Based on this data, structure-activity relationships can be discerned, suggesting compounds of this class are good candidates for analog production.  相似文献   
3.
A formal total synthesis of the marine sesquiterpene (±)-9-isocyanoneopupukeanane starting from the readily available monoterpene carvone has been accomplished employing a combination of intermolecular Michael addition-intramolecular Michael addition reaction and an intramolecular rhodium carbenoid C-H insertion reaction as key steps, and identifying the isopropenyl group as a masked hydroxy group.  相似文献   
4.
贺菊芳  吴毓林 《有机化学》1987,7(5):354-356
近年来有不少报道从事于生理活性Drimane类倍半萜的合成,较多采用了分子间Diels-Alder反应来建立Drimane的骨架。本文首次采用内分子Diels-Alder反应作为关键反应合成了Drimane类化合物。同时还在引入了手性诱导基团后,首次完成了从无手性的原料化合物β-紫罗兰酮至光学活性(-)-drimenin1的不对称合成。  相似文献   
5.
The volatile mono-and sesquiterpenes obtained from the needles and resin of Pinus armandi, P. tabulaeformis, and P. bungeana growing in the Qinling, Taibai, and Huanglong Mountain forest ecosystem were analyzed by means of GC-MS. Forty-eight constituents were identified, and α-pinene, β-pinene, 1R-α-pinene, β-caryophyllene, cadindiene, α-caryophyllene, D-limonene, and 1S-β-pinene were the major components of the mono-and sesquiterpenes in the needles and resin. The components of the volatile mono-and sesquiterpenes from the needles and resin at Qinling, Taibai, and Huanglong Mountains had remarkable differences in three pine species, whereas the monopertene content such as α-pinene, β-pinene, D-limonene, and camphene were mostly changed in the growing stage. The intraspecies variation in the different ecosystems can be attributed to the species’ geography and genetic variation, and even the adaptation of the pine species to different ecological environments. Moreover, monoterpenes and sesquiterpenes can be induced by the attack of bark beetles, of which the α-pinene, β-pinene, 1R-α-pinene, 1S-α-pinene, b-myrecene, and β-caryophyllene contents had positive relations with the attacking Dendroctonus armandi and D. valens. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 430–433, September–October, 2006.  相似文献   
6.
(1) Background: Centaurea cyanus L. is a medicinal plant whose flowers are widely used in herbal medicine. The aim of the study was to localise flower tissues that are responsible for the production of secretory products in petals and to analyse the volatile compounds. The volatile compounds of the flowers of this species have not been investigated to date. (2) Methods: Light, fluorescence, scanning and transmission electron microscopy techniques were used in the study. Lipophilic compounds were localised in the tissues using histochemical assays. Volatile compounds were determined with the use of solid phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS). (3) Results: The study showed production of secretion in the petal parenchyma, whose ultrastructure has features of a secretory tissue. The lipophilic secretion was localised in the cells and intercellular spaces of the parenchyma and in the walls and surface of epidermal cells, where it accumulated after release through cuticle microchannels. Sesquiterpenes were found to constitute the main group of volatile compounds, with the highest content of β-caryophyllene (26.17%) and α-humulene (9.77%). (4) Conclusions: Given the presence of some volatile components that are often found in resins (caryophyllene, delta-cadinene) and the abundant secretion residues on the epidermal surface, we suppose that the C. cyanus secretion released by the flowers is a resinaceous mixture (oleoresin), which is frequently found in plants, as shown by literature data. This secretion may play an important role in the therapeutic effects of C. cyanus flowers.  相似文献   
7.
我们在研究 9-氧代桉烷 - 4-烯 - 3 -酮类化合物的 2 ,3 -二氯 - 5 ,6 -二腈基 - 1 ,4-苯醌 (DDQ)脱氢反应时[1] ,发现 1 4-降桉烷 - 4,1 1 -二烯 - 3 ,9-二酮及其 1 0 - Epimer在 DDQ脱氢条件下发生迁移重排反应 ,生成酚类化合物 .反应式如下 :DDQ脱氢反应已被详细研究 ,并被广泛地用于有机合成中 [2~ 5] ,但这种脱氢重排反应尚未见文献报道 .为了深入研究该反应 ,提出可能的重排机理 .我们参照文献 [6~ 1 0 ]方法 ,用 MVK和 EVK与相应的 2 -甲基 - 1 ,3 -二酮进行 Robinson成环反应 ,合成了一系列具有类似结构的化合物 ,并与 DD…  相似文献   
8.
5α,11-二羟基-2-氧代桉烷-3-(5α-Hydroxy—isopterocarpolone,1)是由贾忠建等于1996年从中药南牡蒿中首次分离得到的一种桉烷型倍半萜类天然产物.桉烷型倍半萜类化合物广泛分布于天然植物中,具有较好的昆虫拒食、抑制细胞繁殖和植物生长调节等多种生理活性.天然产物1的合成研究尚未见报道.  相似文献   
9.
Two new eudesmane sesquiterpene lactones were isolated from the stalk of Lactuca sativa var.anagustata L and their structureswere elucidated by means of spectroscopic methods,including 2D NMR(~1H-~1H COSY,HMBC and NOESY) as 1β-O-β-D-glucopyranosyl-4α-hydroxyl-5α,6β,11βH-eudesma-12,6α-olide(1) and 1β-hydroxyl-15-O-(p-methoxyphenylacetyl)-5α,6β,11βH-eudesma-3-en-12,6α-olide(2).  相似文献   
10.
The components of fragrance from four wormwood species of theArtemisiaL. genus were analyzed by GC-MS. The major and minor components of volatile essential oils typical of the studied plant species were determined.  相似文献   
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