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1.
A convergent synthetic strategy for abietane diterpenoids via B-alkyl Suzuki-Miyaura coupling and Lewis acid-mediated cyclization reactions is established. Asymmetric total synthesis of 12-deoxyroyleanone, an antileishmanial diterpene, is described.  相似文献   
2.
12-Hydroxy-13-methylpodocarpa-9, 11, 13-trien-3-one 9 was isolated from the twigs ofCroton salutaris1. Many diterpenes exhibit significant bioactivities, such as antibac-terial and antitumour and 9 has a rare structure. In order to study the relationshipb…  相似文献   
3.
以2-(3,4-环己基类二氧-5-异丙基)苯基乙醇(2)和3-异丙氧基-5,5-二甲基-1,3-环己烯酮(4)为原料,利用羰基α-位的烷基化反应和分子内的Friedel-Carfts反应为关键步骤,经9步反应,合成了多氧芳香型三环二萜类天然产物Salvinolone。  相似文献   
4.
Extracts of Aconitum septentrionale Koelle roots obtained using chloroform, isopropanol, and ethanol were purified using chloroform and basic γ-Al2O3. Ballast materials were selectively adsorbed by γ-Al2O3, increasing the mass fraction of lappaconitine in the extract. The ethanol extract was purified most. The degree of lappaconitine extraction by chloroform was unaffected by the presence of γ-Al2O3. However, the mass fraction in the extract and lappaconitine extraction from Aconitum septentrionale were increased more than twice. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 274–276, May–June, 2006.  相似文献   
5.
Two new ent‐abietane diterpenoids, macrophynin E ( 1 ) and macrophynin F ( 2 ), and a known related ent‐abietanoid (?)‐lambertic acid ( 3 ), together with four known ent‐kauranoids, were isolated from the roots and aerial parts of Isodon macrophylla, respectively. The structures of the new compounds were elucidated on the basis of spectroscopic‐data analysis and chemical correlations.  相似文献   
6.
A new abietane diterpene 12-hydroxy-7-oxo-5, 8, 11, 13-tetraene-18, 6-abietanolide, together with a new natural sterol stigmasta-7, 22-diene-3β, 5α, 6α-triol have been isolated from the fruiting body of the fungus Phellinus igniarius. Their structures were elucidated by spectroscopic methods including 2D NMR techniques.  相似文献   
7.
Indole diterpenes are a large class of secondary metabolites produced by fungi, possessing a cyclic diterpenoid backbone and an indole moiety. Novel structures and important biological activity have made indole diterpenes one of the focuses of synthetic chemists. Although the discovery, identification, structural diversity, biological activity and especially structure–activity relationship of indole diterpenes have been reported in some papers in recent years, they are absent of a systematic and comprehensive analysis, and there is no elucidation of enzymes related to this kind of natural product. Therefore, it is necessary to summarize the relevant reports to provide new perspectives for the following research. In this review, for the first time, the function of related synthases and the structure–activity relationship of indole diterpenes are expounded, and the recent research advances of them are emphasized.  相似文献   
8.
Two new cembranoid diterpenes, diepoxysarcophytonene ( 1 ) and sarconphytonol ( 2 ), were isolated from the Hainan soft coral Sarcophyton latum. Their structures including relative stereochemistry were established by 1D and 2D NMR spectroscopic techniques. Compound 1 showed weak inhibitory activity against COX‐2 in vitro at the concentration of 10?5 µmol·L?1 with the inhibitory rate of 55%.  相似文献   
9.
对活性天然产物(+)-7-deoxynimbidiol非对映异构体的外消旋体cis-(±)-7-deoxynimbidiol进行了合成和衍生, 共得到了8个新型三环二萜化合物; 对合成的新化合物进行了抗肿瘤活性的实验研究, 其中化合物5d对人体乳腺癌瘤株MCF7表现出了较强的抑制作用(IC50=7.49 μg/mL), 可能作为新型抗肿瘤药物先导化合物.  相似文献   
10.
One new ent-kaurane diterpene derivative (1), along with four known diterpenes, was isolated from the stems of Eurya chinensis R.Br. The structure of the new compound was established by extensive analysis of mass spectrometric and 1D and 2D NMR spectroscopic data. Compound 1 showed moderate anti-inflammatory activities with IC50 value of 8.12 μM. This is the first example of diterpenoids with 4-hydroxy-4-(2-hydroxyethyl)-1-hydroxyl-cyclohexanoyl substituent.  相似文献   
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