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抗生育植物梔子花化学成分的研究 Ⅰ.抗早孕成分梔子花乙酸的结构 总被引:1,自引:0,他引:1
栀子(Gardenia jasminoides Ellis)是我国传统中药,其果实有清热、凉血之功效。用于治疗黄疸、目赤、便血和毒疮等症。民间亦用其花内服抗生育。在筛选抗生育植物药的过程中,发现栀子花的乙酸乙酯粗提物对大鼠有明显的抗早孕作用。高怡生等报道从该粗提取物中分得有抗早孕作用的cycloartane型新二萜酸——栀子酸(gardenic acid)。最近,我们又继续从该粗提取物中分得多种黄酮、环烯醚萜、三萜酸和甾醇类化合物。其中一个cycloartane型新三萜酸——栀子花乙酸(gardenolic acid B)经药理试验证明对大鼠也有抗早孕作用,本文报道它的结构研究. 相似文献
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Two new polytriazines: poly[2-methyl-4, 6-(4,′4″-diphenylene)-1, 3, 5-triazine] (Ⅰ) and poly[2-phenyl-4, 6-(4′, 4″-diphenylene)-1, 3, 5-triazine] (Ⅱ) were synthesized from the solution condensation of biphenyl-4, 4′-diamidine dihydrochloride with acetic anhydride and biphenyl-4, 4′-diamidine with benzaldehyde respectively. These two polymers were characterized by TGA, DTA, elemental analysis and IR spectroscopy. They exhibited good thermal oxidative stability as shown by the fact that the powders of these polymers suffered 5.4%, 2.4% weight loss after isothermal aging in air at 300℃for 200 hours. The decomposition temperature of (Ⅱ) was 583℃in air and 590℃in N_2. These linear poly-1, 3, 5-triazines were soluble in concentrated sulfuric acid, phosphoric acid and trifluoroacetic acid whereas the erosslinked poly-1, 3, 5-triazines reported in the literature were insoluble and infusible.It is interesting that these polymers can form complexes with metal halides as determined by X-ray photoelectron spectroscopy (XPS). The polymer metal complex (Ⅲ). PdCl_2 possesses catalytic activity for hydrogenation. 相似文献
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用Syntex P3四圆衍射仪收集氯化邻乙氧羰基苯汞晶体的三维衍射数据,晶体属单斜晶系;空间群为C2h[5]-P21/c;a=10.611(2)A,b=4.987(1)A,c=19.416(5)A,β=95.74(2);z=4,利用Patterson法和直接法测定了晶体结构,用块矩阵最小二乘法修正后,最终R值为0.044.晶体结构分析表明,在氯化邻乙氧羰基苯汞分子中存在有分子内配位,Hg...O(1)的间距为2.734A。 相似文献
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共享经济作为经济发展新范式,有效实现了社会资源的价值再创造,目前共享经济发展面临市场监管不完善、第三方平台利益垄断、消费者权益受到侵害等问题,如何实现共享经济创新规范性发展已成为社会各界关注的热点.区块链去中心化、不可篡改、可追溯、多方维护等技术特质在解决共享经济困境具有独特优势.从区块链与共享经济融合发展角度出发,建立政府、平台企业与消费者三方策略选择演化博弈模型,探讨不同条件下三方策略选择的影响因素,并利MATLAB进行仿真分析.研究结果表明:政府、平台企业和消费者之间的策略选择与政府的罚金力度负相关、与消费者和共享平台利润机制正相关,区块链技术对于激发共享经济新活力具备正向作用. 相似文献