共查询到19条相似文献,搜索用时 375 毫秒
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天然产物1,3-二-(2-羟基-4-甲氧基苯基)丙烷和1,3-二-(2,4-二羟基苯基)丙烷的合成 总被引:2,自引:0,他引:2
1,3-二-(2-羟基-4-甲氧基苯基)丙烷(1)和1,3-二-(2,4-二羟基苯基)丙烷(2)是从菊叶薯蓣(Dioscorea composita Hemsl.)分离出来的天然产物, 以间苯二酚为起始原料, 分别经甲酰化和乙酰化得到2,4-二羟基苯甲醛和2,4-二羟基苯乙酮, 然后经选择性地甲基化、甲氧甲基化、羟醛缩合、还原、脱保护等步骤完成了上述两种天然产物的首次全合成. 产物通过1H NMR, IR, MS进行了结构确证. 相似文献
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N-酰亚甲基-2-吡啶酮是一类非常重要的结构单元, 广泛存在于天然产物和其它具有生物活性的化合物中. 其合成通常是通过2-羟基吡啶与相应的亲电试剂发生分子间亲核取代反应. 然而, 由于2-羟基吡啶的双亲核特性, 这一方法往往面临着N/O化学选择性难以控制的问题. 报道了一例钯催化三组分烯丙基取代反应, 化学专一性地合成难以构建的大位阻N-酰亚甲基-2-吡啶酮衍生物, 收率最高可达98%, 未见有O-烷基化副产物的生成. 该反应可以在克级规模下进行, 依然取得98%的收率. 本方法所得到的N-酰亚甲基-2-吡啶酮产物经过简单转化, 可方便地制得含吡啶酮结构的非天然氨基酸类化合物. 实验结果显示, 该三组分反应是经过一个串联的亲核取代和烯丙基取代反应而专一性地合成N-酰亚甲基-2-吡啶酮衍生物. 相似文献
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以丙二酸和二氯亚砜为起始原料,经氯代、环合、催化氢化及烷基化反应合成了新化合物——N-甲基-5-苯基-4-羟基-2-吡啶酮,总收率38.7%,其结构经1H NMR,IR和EI-MS表征. 相似文献
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3,5-二羟基-7,4′-二甲氧基二氢黄酮醇(1)从Cephalanthus spathelliferus中分离得到后[1], 又在Haplopappus bayahuen[2]和Lannea coromandelica[3]等植物中被发现, 在印度一直被用于治疗象皮病、阳痿、溃疡、阴道炎、口臭、痢疾和风湿病等. 3,5,7-三羟基-4′-甲氧基二氢黄酮醇(2)首次从Prunus donestica[4]中分离出来后, 又从Salix caprea L., Brazilian propolis中得到. 研究表明, 该化合物具有抗菌、抗肿瘤活性. 我们用与文献[5]类似的方法以2, 4, 6-三羟基苯乙酮和茴香醛为起始原料, 经选择性保护、缩合、环氧化、关环首次完成了化合物(±)-1和(±)-2的全合成. 合成路线如下: 相似文献
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This paper presents a review on kaurane diterpenes and their glycoside derivatives, covering aspects of their occurrence, biological activities and the synthesis of these natural products and their analogues. First, it shows and classifies diterpenes, in accordance with the already established structural criteria in the literature. Then, kaurane diterpenes are presented, focusing on their chemical structures, occurrence in the plant kingdom and their main, recently described, biological activities. Moreover, the most significant works, published between 1964 and November 2006, which describe the total synthesis or structural transformations of some kaurane diterpenes, including either semisynthetic and/or microbiological methodologies, are consisely reviewed. At this point, some general considerations on glycosides are introduced, and kaurane glycosides are presented and discussed on the basis of their toxic importance and occurrence in the plant kingdom, having focused on related aspects of their biological activities and the relationships between these activities and the structural factors of their molecules. Finally, the principal methods of glycosidation by enzymatic and chemical processes are both presented, and a few papers on the synthesis of kaurane glycosides are succinctly discussed. 相似文献
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Behenna DC Stockdill JL Stoltz BM 《Angewandte Chemie (International ed. in English)》2008,47(13):2365-2386
Marine natural products have long played an important role in natural products chemistry and drug discovery. Mirroring the rich variety and complicated interactions of the marine environment, the substances isolated from sea creatures tend to be incredibly diverse in both molecular structure and biological activity. The natural products isolated from the polyps of marine zoanthids are no exception. The zoanthamine alkaloids, the first of which were isolated over 20 years ago, are of particular interest to the synthetic community because they feature a novel structural framework and exhibit a broad range of biological activities. In this Review, we summarize the major contributions to understanding the zoanthamine natural products with regard to their isolation and structure determination, as well as studies on their biological activity and total synthesis. 相似文献
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Leander Geske Ulrich Kauhl Mohamed E. M. Saeed Anja Schüffler Eckhard Thines Thomas Efferth Till Opatz 《Molecules (Basel, Switzerland)》2021,26(11)
The biological activities of shancigusin C (1) and bletistrin G (2), natural products isolated from orchids, are reported along with their first total syntheses. The total synthesis of shancigusin C (1) was conducted by employing the Perkin reaction to forge the central stilbene core, whereas the synthesis of bletistrin G (2) was achieved by the Wittig olefination followed by several regioselective aromatic substitution reactions. Both syntheses were completed by applying only renewable starting materials according to the principles of xylochemistry. The cytotoxic properties of shancigusin C (1) and bletistrin G (2) against tumor cells suggest suitability as a starting point for further structural variation. 相似文献
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Inoue M 《Organic & biomolecular chemistry》2004,2(13):1811-1817
One of the most characteristic and spectacular class of compounds isolated from marine sources is the polycyclic ethers. Following the initial report of the structural determination of brevetoxin B, a variety of novel polycyclic ethers have begun to surface. These natural products include ciguatoxins, gambierol, gambieric acids, yessotoxins and gymnocins, each of which exhibit distinct biological properties such as cytotoxicity and neurotoxicity, as well as antiviral and antifungal activities. Because of these intriguing biological activities and their complex molecular architecture, the total synthesis of these compounds has been pursued by many laboratories over two decades. In particular, the development of novel convergent strategies to assemble the structural fragments is crucial for the successful construction of these nano-scale molecules. This Perspective will focus on a recent convergent methodology using an acetal-linkage as a key motif. Application of this methodology culminated in the total syntheses of gambierol and ciguatoxin CTX3C. 相似文献
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In recent years, the synthesis and pharmacology of pyranoflavanoids have been extensively investigated due to their wide range of pharmacological properties[1-3]. Ponganone Ⅲ[4],a new natural pyranoflavanone isolated from the Pongamia pinnala, was identified as (2S)-3',4'-dimethoxy-6',6"-dimethylpyrano-[2",3":7,8]-flavanone (2) on the basis of spectra data. Its precursor,3,4-dimethoxy-2'-hydroxy-6",6"-dimethylchromeno-[2",3":4',3']-chalcone (1) is also a new natural product[5] isolated from the roots of Lonchocarpus subglaucescent. Their total synthesis have not been reported. Herein, we wish to report the first total synthesis of compounds 1 and 2 in order to confirm the proposed structure and further more to evaluate its biological activities. 相似文献
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Cyclopropane fatty acids (CFAs) and related compounds containing CFAs commonly occur in various natural sources, including plants or microorganisms. Some CFAs exhibit intriguing biological activities such as antifungal or immunosuppressive activities. Due to their biological importance and structural features, a number of synthetic studies have been conducted to date. These total syntheses have helped to elucidate their structural determinants or biological activities. Herein the total syntheses of naturally occurring CFAs and related compounds are summarized. 相似文献
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Celastraceae sesquiterpenoids: biological activity and synthesis 总被引:1,自引:0,他引:1
Plant extracts of the Celastraceae have been used for centuries throughout South America and China as insect repellents and insecticides in traditional agriculture, and also for the treatment of a plethora of medical ailments from stomach complaints and fever to rheumatoid arthritis and cancer. Many of the medicinally interesting properties associated with these crude preparations have now been attributed to a large family of highly oxygenated sesquiterpenoids based on a tricyclic dihydroagarofuran skeleton. In this article, the structural diversity and range of biological activities associated with this intriguing class of natural products are examined with a view to stimulating interest in their total synthesis. Existing synthetic endeavours towards their synthesis are also evaluated. 相似文献
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Hai-Bo Qiu Xin-Ya ChenQing Li Wen-Jian QianShun-Ming Yu Gong-Li TangZhu-Jun Yao 《Tetrahedron letters》2014
A practical HPLC-free total synthesis of chlorofusin has been successfully accomplished in this work. The new synthesis showed great flexibility and convenience in generating artificial natural product-like mimics through Click chemistry, and enabled us to further investigate the biological importance of the chromophore and the spiro-aminal functionality of the natural product. The entire skeleton is believed to be essential for satisfactory biological activities of both natural chlorofusin and unnatural mimics. Two artificial Click hybrids were found to exhibit improved inhibitory activity against p53–HDM2 bindings over the natural product. 相似文献