排序方式: 共有120条查询结果,搜索用时 296 毫秒
41.
A. D. Shinde S. S. Sonar B. B. Shingate M. S. Shingare 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1594-1603
We describe the synthesis of novel thiadiazole, selenadiazole, and spirocyclic benzopyrans via the semicarbazides 3 and thiosemicarbazides 3 of 2-ethyl-2-methyl-4H-chromen-4-ones 1 by conventional and nonconventional methods. The microwave and ultrasonic irradiation methods form the respective products in excellent yields in very short reaction time as compared to the conventional method. The synthesized compounds were tested for antimicrobial screening against bacteria and fungi show moderate activity. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
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Unified Total Syntheses of (−)‐Medicarpin, (−)‐Sophoracarpan A,and (±)‐Kushecarpin A with Some Structural Revisions
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Zhen‐Gao Feng Wen‐Ju Bai Prof. Thomas R. R. Pettus 《Angewandte Chemie (International ed. in English)》2015,54(6):1864-1867
The total syntheses of medicarpin, sophoracarpan A, and kushecarpin A from a common intermediate are achieved by using ortho‐ and para‐quinone methide chemistry. Additionally, the relative stereochemistry of sophoracarpan A and B have been reassigned. 相似文献
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Friederike M. Wunsch Bernhard Wünsch Freddy A. Bernal Thomas J. Schmidt 《Molecules (Basel, Switzerland)》2021,26(17)
On the basis of the finding that various aminoalkyl-substituted chromene and chromane derivatives possess strong and highly selective in vitro bioactivity against Plasmodium falciparum, the pathogen responsible for tropical malaria, we performed a structure–activity relationship study for such compounds. With structures and activity data of 52 congeneric compounds from our recent studies, we performed a three-dimensional quantitative structure–activity relationship (3D-QSAR) study using the comparative molecular field analysis (CoMFA) approach as implemented in the Open3DQSAR software. The resulting model displayed excellent internal and good external predictive power as well as good robustness. Besides insights into the molecular interactions and structural features influencing the antiplasmodial activity, this model now provides the possibility to predict the activity of further untested compounds to guide our further synthetic efforts to develop even more potent antiplasmodial chromenes/chromanes. 相似文献
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苯并吡喃-4-硫脲类化合物的合成及其血管舒张活性 总被引:2,自引:0,他引:2
根据苯并吡喃类钾通道开放剂的作用机理和构效关系,合成了4个新的苯并吡喃-4-硫脲类化合物(3a~3d),其结构经1HNMR,IR,MS和元素分析确证。大鼠体外血管扩张实验结果表明,3(1.0×10-5mol·L-1)对30mmol·L-1KCl诱导的大鼠主动脉条收缩均具有一定程度的抑制作用,其中3a的血管收缩抑制活性较强。 相似文献
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Ming Hu Xue-Qiong Yang Qing-Yan Zhou Shu-Quan Li Bang-Yan Wang Bao-Hui Ruan 《Natural product research》2019,33(10):1431-1435
Five new benzopyran derivatives (2–6) and a new natural product (1) were isolated from endophytic Daldinia eschscholzii in Dendrobium chrysotoxum and determined as (R)-2,3-dihydro-2,5-dihydroxy-2-methylchromen-4-one (1), (2R, 4S)-2,3-dihydro-2-methyl-benzopyran-4,5-diol (2), (R)-3-methoxyl-1-(2,6-dihydroxy phenyl)-butan-1-one (3), 7-O-α-d-ribosyl-5-hydroxy-2-methyl-4H-chromen-4-one (4), 7-O-α-d-ribosyl-2,3-dihydro-5-hydroxy-2-methyl-chromen-4-one (5), daldinium A (6). These compounds were evaluated for their antimicrobial activity, anti-acetylcholinesterase, nitric oxide inhibition, anticoagulant, photodynamic antimicrobial activities and glucose uptake of adipocytes. Some compounds showed photoactive antimicrobial activities and glucose uptake stimulating activities. 相似文献
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A mild and efficient protocol for the synthesis of the benzopyran ring has been described and a series of chromans compounds is reported, the yield is from 72% to 95%. The diadduct tended to angular product and showed good regioselectivity. This strategy was applied for the benzopyran derived natural products (±)‐xyloketals and (±)‐alboatrin. The crystal of compound 9 exhibited centro‐symmetric space group, containing two isomers in one unit. The relative configurations were 1R,10R,15S and 34S,22R,30S, respectively. 相似文献
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Nicky J. Willis Dr. Christopher D. Bray 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(30):9160-9173
ortho‐Quinone methides (o‐QMs) are emerging as highly useful intermediates, the inherent reactivity of which can be used in linchpin reactions for the construction of complex natural products. This review encompasses the major contributions in this field, exemplifying the major strategies and reactivity modes which can be applied. 相似文献
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An efficient and simple synthesis of substituted 3‐phenyl‐7‐methoxybenzopyrans as pseudo‐vitamin‐D3 analogs in good yields under mild reaction conditions is described. 相似文献