117156-85-1Relevant academic research and scientific papers
Prenylcoumarins in One or Two Steps by a Microwave-Promoted Tandem Claisen Rearrangement/Wittig Olefination/Cyclization Sequence
Schultze, Christiane,Schmidt, Bernd
, p. 5210 - 5224 (2018/05/17)
The one-pot synthesis of 8-prenylcoumarins from 1,1-dimethylallylated salicylaldehydes and the stabilized ylide [(ethoxycarbonyl)methylene]triphenylphosphorane under microwave conditions was found to have a limited scope. The sequence suffers from a difficult and sometimes low-yielding synthesis of the precursors and from a competing deprenylation upon microwave irradiation. This side reaction occurs in particular with electron rich arenes with two or more alkoxy groups at adjacent positions, a prominent substitution pattern in naturally occurring 8-prenylcoumarins. Both limitations of this one-step sequence were overcome by a two-step synthesis consisting of a microwave-promoted tandem allyl ether Claisen rearrangement/Wittig olefination and a subsequent olefin cross metathesis with 2-methyl-2-butene. The cross metathesis step proceeds with a high selectivity and yields exclusively the desired prenyl, rather than the alternative crotyl substituent. Several naturally occurring 8-prenylcoumarins that were previously inaccessible have been synthesized in good overall yields along this route.
Visible-Light-Induced External Radical-Triggered Annulation to Access CF2-Containing Benzoxepine Derivatives
Xiang, Haoyue,Zhao, Qing-Lan,Xia, Peng-Ju,Xiao, Jun-An,Ye, Zhi-Peng,Xie, Xiong,Sheng, Huan,Chen, Xiao-Qing,Yang, Hua
supporting information, p. 1363 - 1366 (2018/03/09)
A facile and diversified synthesis of functionalized CF2-containing benzoxepine derivatives via photoredox catalysis was achieved in this work. This novel protocol features broad substrate scope, mild reaction conditions, operational simplicity, easy scale-up, and versatile derivatization, which would facilitate its practical and broad applications in the construction of valuable and synthetically challenging heterocycles.
Synthesis of Chromones from 1,1-Diacylcyclopropanes: Toward the Synthesis of Bromophycoic Acid e
Smith, Robert J.,Nhu, Duong,Clark, Mitchell R.,Gai, Sinan,Lucas, Nigel T.,Hawkins, Bill C.
, p. 5317 - 5327 (2017/05/24)
A tandem deprotection-cyclization reaction of 1,1-diacylcyclopropanes is described which allows rapid access to structurally diverse 2,3-disubstituted chromones in good yields, and with straightforward purification. The utility of this reaction is showcas
Glucose uptake enhancing activity of puerarin and the role of C-glucoside suggested from activity of related compounds
Kato, Eisuke,Kawabata, Jun
supporting information; experimental part, p. 4333 - 4336 (2010/09/18)
Chemical treatment of diabetes mellitus is widely studied and controlling of blood glucose level is the main course of therapy. In type 2 diabetes mellitus, insulin resistance is the major problem. An isoflavone C-glucoside, puerarin (1), is known to enhance glucose uptake into the insulin sensitive cell and is thought to be a candidate for treatment of diabetes mellitus. We synthesized 1 and several derivatives to apply for the structure-activity relationship study. The result against 3T3-L1 adipocyte indicated that the C-glucoside part of 1 is unconcerned in its activity when tested in vitro and the main structure responsible for its activity was the isoflavone moiety.
Indole derivative having piperidine ring
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Page/Page column 54, (2008/06/13)
The present invention relates to a compound represented by the following formula, a pharmacologically acceptable salt thereof, or a use thereof as a pharmaceutical: wherein R1 and R2 are substituents adjacent to each other, and together with two carbon atoms to each of which they attach, form a 5- to 7-membered non-aromatic carbocyclic group or the like, which may be substituted by 1 to 4 substituents selected from (1) an oxo group, (2) a hydroxyl group, and the like; R3 represents a hydrogen atom or the like; and R6 represents a hydrogen atom or the like. It is an object of the present invention to discover an agent for treating or preventing lower urinary tract symptoms, and particularly symptoms regarding urinary storage, which has a superior strength of binding to a 5-HT1A receptor and an antagonism to the receptor.
Thermal Claisen Rearrangement Studies on 4,6- and 2,4-Diacetylresorcinol Bisallyl Ethers: Observation of Loss or Sigmatropic Shift of Acetyl Groups
Anjaneyulu, Ammanamanchi S. R.,Mallavadhani, Uppuluri V.
, p. 623 - 628 (2007/10/02)
Thermal Claisen rearrangement of 4,6-diacetylresorcinol bisallyl ether (2) in N,N-dimethylaniline gave a mixture of readily characterised products.While no rearrangement occurred with lower boiling solvents (benzene and dioxane), higher boiling solvents (diphenyl ether and glycerol) gave rise to more complex rearrangement and a lowering of the yields of isolable products.Trifluoroacetic acid both at room temperature and 60 deg C effected either partial or total deallylation but no rearrangement.Product formation has been rationalised in terms of symmetry allowed sigmatropic allyl, acetyl or H shifts followed by allyl or acetyl group loss; the latter is a novel obsrevation.The acetyl group, most probably eliminated as a cation, effected both O-acylation and nuclear acylation of the substrates.Claisen rearrangement of the bromo and nitro derivatives of compound (2) in which the ortho and para positions are blocked, gave products arising from bromo and nitro group elimination.Rearrangement of 2,4-diavetylresorcinol bisallyl ether N,N-dimethylaniline occurred similarly.
