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1.
Lathyranone A: a diterpenoid possessing an unprecedented skeleton from Euphorbia lathyris 总被引:1,自引:0,他引:1
Lathyranone A (1), a novel diterpenoid with a rearrangement skeleton, along with a known diterpenoid, Euphorbia factor L(11) (2), was isolated from the seeds of Euphorbia lathyris. The structure and relative stereochemistry of 1 were elucidated by extensive spectroscopic analysis. A possible biosynthetic pathway for lathyranone A (1) was proposed. 相似文献
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Rakesh Sarin Deepak Kumar Tuli Shanti Prakash Krishan Kumar Swami Akhilesh Kumar Bhatnagar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1763-1766
Phosphorus components are probably the earliest known and most important additives for lubricant applications. Phosphites, phosphates, thiophosphates, metal dithiophosphates, and amine phosphates are examples of common phosphorus additives being used in the lubricant industry. However, due to environmental concerns and to help conserve catalyst life of catalytic converters, there is a trend to reduce the phosphorus content in lubricant formulations. In order to achieve this goal, different types of phosphorus components have been studied for their tribological properties. 相似文献
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我国对抗高血压药的研究始于20世纪50年代。随着研究的不断深入,抗高血压药物朝着高效、长效、高度心血管选择性、多器官保护作用以及低副作用方向发展,不断在原有化合物模型的基础上对化合物进行结构修饰,发展了单环及多环含氮杂环类抗高血压药物。文章从结构与活性的角度分析了近年来国内外杂环类抗高血压药及其衍生物的构效关系。 相似文献
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U. N. Zainutdinov R. Islamov D. N. Dalimov T. R. Abdurakhmanov O. D. Matchanov N. L. Vypova 《Chemistry of Natural Compounds》2002,38(2):161-163
The structure-hemostatic activity relationship of lagochilin and its natural and synthetic derivatives was investigated. 相似文献
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A new synthetic route for a pseudoguaiane ring system is described. The synthesis features an Ireland-Claisen rearrangement for constructing the trans-fused ring system, followed by a new ring expansion to yield a bicyclo[5.3.0]decane ring system possessing an angular methyl group. 相似文献
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Xiao WL Li RT Li SH Li XL Sun HD Zheng YT Wang RR Lu Y Wang C Zheng QT 《Organic letters》2005,7(7):1263-1266
[structures: see text] Lancifodilactone F (1), possessing an unprecedented rearranged pentanortriterpenoid backbone derived from cycloartane, was isolated from the leaves and stems of Schisandra lancifolia (Rehd. et Wils) A. C. Smith. Its structure was established by comprehensive NMR and MS spectroscopic analysis, coupled with single-crystal X-ray experiment. Compound 1 exerted minimal cytotoxicity against C8166 cells (CC50 > 200 microg/mL) and showed anti-HIV activity with EC50 = 20.69 +/- 3.31 microg/mL and a selectivity index > 6.62. 相似文献
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Kadlongilactones A and B, two novel triterpene dilactones from Kadsura longipedunculata possessing a unique skeleton 总被引:3,自引:0,他引:3
Pu JX Xiao WL Lu Y Li RT Li HM Zhang L Huang SX Li X Zhao QS Zheng QT Sun HD 《Organic letters》2005,7(22):5079-5082
[structure: see text] Two novel triterpene dilactones with an unprecedented rearranged hexacyclic skeleton, kadlongilactones A (1) and B (2), have been isolated from the leaves and stems of Kadsura longipedunculata Finet et Gagnep (Schisandraceae). Their structures were established by comprehensive 1D and 2D NMR spectroscopic analysis, coupled with single-crystal X-ray crystallographic diffraction. Compounds 1 and 2 exerted significant inhibitory effects against human tumor K562 cells with IC(50) = 1.40 and 1.71 microg/mL, respectively. 相似文献
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Jian-Xin Pu Wei-Lie Xiao Sheng-Xiong Huang Qi-Tai Zheng Han-Dong Sun 《Tetrahedron》2006,62(25):6073-6081
Nine novel triterpene dilactones with an unprecedented rearranged pentacyclic skeleton, longipedlactones A-I (1-9), have been isolated from the leaves and stems of Kadsura longipedunculata Finet et Gagnep (Schisandraceae). Their structures were determined on the basis of comprehensive spectroscopic analysis and single-crystal X-ray structure determination. A biogenetic pathway for longipedlactone A (1) was also proposed. Compounds 1-3, 6, and 8 showed significant cytotoxicity against A549, with HT-29 and K562 cell lines having IC50 values of 0.84-11.38 μM in vitro. 相似文献
9.
The structure-activity relationship of °uoroquinolones, which show anti-K. pneumoniae activity, was studied by using principal component analysis (PCA) and hierarchical cluster analysis (HCA). The PCA results showed that the lowest unoccupied molecular orbital energy, energy difference between the highest occupied and the lowest unoccupied molecular orbital, dipole moment, net atomic charge on atom I, molecular polarizability, partition coe±cient and molecular refractivity of these compounds are responsible for the separation between high-activity and low-activity groups. The HCA results were similar to those obtained with PCA. By using the chemometric results, four synthetic compounds were analyzed through PCA and HCA, and three of them are proposed as active molecules against K. pneumoniae which is consistent with the results of clinical experiments. The methodologies of PCA and HCA provide a reliable rule for classifying new °uoroquinolones with anti-K. pneumoniae activity. 相似文献
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Dong M Cong B Yu SH Sauriol F Huo CH Shi QW Gu YC Zamir LO Kiyota H 《Organic letters》2008,10(5):701-704
Echinopines A (1) and B (2), novel sesquiterpenoids with an unprecedented rearranged skeleton named echinopane, were isolated from the roots of Echinops spinosus. The structures were elucidated by extensive spectroscopic analysis. The relative configuration of 1 was assigned by a combination of NOESY correlations and a simulation analysis. A plausible biosynthetic pathway for echinopane was discussed. 相似文献
12.
Dr. Yang Liu Dr. Fang Zhou Kang Ding Dr. Dongxiang Xue Zhihao Zhu Cuixia Li Fei Li Dr. Yueming Xu Prof. Fei Xu Prof. Zhiping Le Prof. Suwen Zhao Prof. Houchao Tao 《ChemistryOpen》2021,10(10):1028-1032
An underside binding site was recently identified in the transmembrane domain of smoothened receptor (SMO). Herein, we report efforts in the exploration of new insights into the interactions between the ligand and SMO. The hydantoin core in the middle of the parent compound was found to be highly conservative in chirality, ring size, and substituents. On each benzene at two ends, a plethora of variations, particularly halogen substitutions, were introduced and investigated. Analysis of the structure-activity relationship revealed miscellaneous halogen effects. The ligands with double halogen substituents exhibit remarkably enhanced potency, providing promising candidates that potentially overcome the common drug resistance and useful heavy-atom labeled chemical tools for co-crystallization studies of SMO. 相似文献
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本文对橙酮类DRAK2抑制剂的化学结构与生物活性之间的关系进行研究。采用三维定量构效关系(3D-QSAR)中的比较分子力场分析(CoMFA)和比较分子相似性指数分析(CoMSIA)方法针对59个DRAK2抑制剂建立3D-QSAR模型,阐明了抑制剂化学结构与其生物活性之间的关系。所构建的CoMFA模型交叉验证系数(q2)为0.625,非交叉验证系数(r2)为0.811,标准偏差(S)为0.365,Fisher检验值(F)为59.971;所构建的CoMSIA模型q2为0.62,r2为0.846,S为0.333,F值为56.453。内部和外部验证参数表明,生成的3D-QSAR模型均具有良好的预测能力和显著的统计学可靠性。分子对接实验与等势图的一致性,进一步表明本次分子模拟是可靠的。本研究对发现新型的潜在的更高活性的橙酮类DRAK2抑制剂具有指导意义。 相似文献
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We describe herein the synthesis and properties of the novel nucleoside derivative, 4,7-diamino-2-(2-deoxy-β-d-erythro-pentofuranosyl)-2,6-dihydro-7H-2,3,5,6-tetraazabenzo[cd]azulene (1). The palladium catalyzed cross-coupling reaction of 2,4-diamino-5-iodo-7-(2-deoxy-β-d-erythro-pentofuranosyl)pyrrolo[2,3-d]pyrimidine (9) with acrylonitrile afforded 2,4-diamino-5-[(E)-1-cyano-2-ethenyl]-7-(2-deoxy-β-d-erythro-pentofuranosyl)pyrrolo[2,3-d]pyrimidine (10) in 77% yield, which was treated with NaOMe in MeOH in the presence of NaSPh to give the desired 1 in 64% yield. Whereas 1 was stable in concentrated ammonia at room temperature, it was gradually hydrolyzed in water to give 4-amino-2-(2-deoxy-β-d-erythro-pentofuranosyl)-2,6-dihydro-7H-2,3,5,6-tetraazabenzo[cd]azulen-7-one (12). Density functional calculations indicated that 12 was 20 kcal/mol more thermodynamically stable than 1 in a model study. 相似文献
16.
Jean‐Marc Gaudin Olga Nikolaenko Jean‐Yves de Saint Laumer Beat Winter Pierre‐Alain Blanc 《Helvetica chimica acta》2007,90(7):1245-1265
We synthesized or re‐synthesized a large series of 2H‐1,5‐benzodioxepin‐3(4H)‐ones 9 (Scheme 1), 4,5‐dihydro‐1‐benzoxepin‐3(2H)‐ones 10 (Schemes 3 and 4) and 5,6,8,9‐tetrahydro‐7H‐benzocyclohepten‐7‐ones 11 (Schemes 5 and 6), since the lead compound for the olfactory note of perfumes based on marine accords is a well‐known benzodioxepinone named Calone 1951® ( 9b ). We meticulously described the odor profile of each synthesized compound and discussed relevant structure–odor relationships (Tables 1–3). In particular, we revealed a correlation between the conformation of the seven‐membered ring and the activities of these compounds (Table 4 and Fig. 3). We also clarified the effect of the position and the size of the alkyl substituent at the aromatic ring. 相似文献
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强镇痛活性生物碱Epibatidine及其类似物的构效关系研究徐建平,何东,王志中,沈家骢,高连勋,宋雅茹(吉林大学化学系理论化学研究所,长春,130023)(中国科学院长春应用化学研究所)(北京师范大学化学系)关键词Epibatidine,AM1,... 相似文献
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