- Diastereoselective photocycloaddition reactions of 2-naphthalenecarboxylates and 2,3-naphthalenedicarboxylates with furans governed by chiral auxiliaries and hydrogen bonding interactions
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By using chiral auxiliaries and hydrogen bonding interactions, we have developed diastereoselective photocycloaddition of 2-naphthalenecarboxylates and 2,3-naphthalenedicarboxylates with furan derivatives. In photoreactions of (?)-menthyl 2-naphthalenecarboxylate with furan and 3-furanmethanol, respective maximum 48% and 40% diastereomeric excesses (d.e.) are observed. In photoreactions of di-8-phenyl-(?)-menthyl 2,3-naphthalenedicarboxylate with 3-furanmethanol, maximum 67% d.e. is obtained. Use of solvents of low polarity, low temperatures and low furan concentration leads to increased diastereoselectivities. Variable-temperature (VT) NMR and fluorescence quenching studies indicate that hydrogen bonding interactions between the carbonyl oxygen of naphthalenecarboxylic acid esters and the OH group in 3-furanmethanol take place in both the ground and excited states. The results of computational studies show that geometries of C2 symmetric naphthalenedicarboxylate reactants are important in governing the high diastereoselectivity in the photoreactions of 2,3-naphthalenedicarboxylates.
- Maeda, Hajime,Koshio, Norihiro,Tachibana, Yuko,Chiyonobu, Kazuhiko,Konishi, Gen-ichi,Mizuno, Kazuhiko
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- Development of Glucose Regulated Protein 94-Selective Inhibitors Based on the BnIm and Radamide Scaffold
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Glucose regulated protein 94 (Grp94) is the endoplasmic reticulum resident of the heat shock protein 90 kDa (Hsp90) family of molecular chaperones. Grp94 associates with many proteins involved in cell adhesion and signaling, including integrins, Toll-like receptors, immunoglobulins, and mutant myocilin. Grp94 has been implicated as a target for several therapeutic areas including glaucoma, cancer metastasis, and multiple myeloma. While 85% identical to other Hsp90 isoforms, the N-terminal ATP-binding site of Grp94 possesses a unique hydrophobic pocket that was used to design isoform-selective inhibitors. Incorporation of a cis-amide bioisostere into the radamide scaffold led to development of the original Grp94-selective inhibitor, BnIm. Structure-activity relationship studies have now been performed on the aryl side chain of BnIm, which resulted in improved analogues that exhibit better potency and selectivity for Grp94. These analogues also manifest superior antimigratory activity in a metastasis model as well as enhanced mutant myocilin degradation in a glaucoma model compared to BnIm.
- Crowley, Vincent M.,Khandelwal, Anuj,Mishra, Sanket,Stothert, Andrew R.,Huard, Dustin J. E.,Zhao, Jinbo,Muth, Aaron,Duerfeldt, Adam S.,Kizziah, James L.,Lieberman, Raquel L.,Dickey, Chad A.,Blagg, Brian S. J.
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p. 3471 - 3488
(2016/05/19)
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- One-step synthesis of furan-2,5-dicarboxylic acid from furan-2-carboxylic acid using carbon dioxide
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A short and effective method for preparation and isolation of furan-2,5-dicarboxylic acid has been developed. Furan-2,5-dicarboxylic acid was prepared directly from furan-2-carboxylic acid in one step under strong basic conditions using carbon dioxide. This method allows to obtain the product with high added value, furan-2,5-dicarboxylic acid, from natural sources such as hemicelluloses containing pentoses. ARKAT-USA, Inc.
- Fischer, Robert,Fiserova, Maria
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p. 405 - 412
(2014/01/23)
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- Cycloaddition of C-3 substituted furans. Stereoselectivity induced by coordination effects
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Several C-3 substituted furans with chelating groups have been reacted with 2,3-dibromo-3-pentanone in the presence of a reducing metal, resulting in the formation of [4+3]-cycloadducts with complete cis-trans and endo-exo diastereoselectivity and in excellent yield. A certain variability of the conversion and reaction yield could be observed, when changing the reaction conditions, but in all cases the stereoselectivity was complete, compared to that of C-3 substituted furans with non-chelating groups. Also, a general method of assignment of stereochemistry of cycloadducts has been established by NMR, considering diagnostic patterns of signals with different multiplicity and chemical shifts depending on the stereochemistry of diastereomeric cycloadducts.
- Montana, Angel M.,Castellvi, Maria,Batalla, Consuelo,Grima, Pedro M.,Font-Bardia, Merce
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p. 9982 - 9998,17
(2012/12/12)
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- Cycloaddition of C-3 substituted furans. Stereoselectivity induced by coordination effects
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Several C-3 substituted furans with chelating groups have been reacted with 2,3-dibromo-3-pentanone in the presence of a reducing metal, resulting in the formation of [4+3]-cycloadducts with complete cis-trans and endo-exo diastereoselectivity and in excellent yield. A certain variability of the conversion and reaction yield could be observed, when changing the reaction conditions, but in all cases the stereoselectivity was complete, compared to that of C-3 substituted furans with non-chelating groups. Also, a general method of assignment of stereochemistry of cycloadducts has been established by NMR, considering diagnostic patterns of signals with different multiplicity and chemical shifts depending on the stereochemistry of diastereomeric cycloadducts.
- Monta?a, ángel M.,Grima, Pedro M.,Castellví, María,Batalla, Consuelo,Font-Bardia, Mercè
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p. 9982 - 9998
(2013/01/14)
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- Substituted 3-aryl-5-aryl-[1,2,4]-oxadiazoles and analogs as activators of caspases and inducers of apoptosis and the use thereof
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The present invention is directed to substituted 3-aryl-5-aryl-[1,2,4]-oxadiazoles and analogs thereof, represented by the Formula I: wherein Ar1, Ar3, A, B and D are defined herein. The present invention also relates to the discovery that compounds having Formula I are activators of caspases and inducers of apoptosis. Therefore, the activators of caspases and inducers of apoptosis of this invention may be used to induce cell death in a variety of clinical conditions in which uncontrolled growth and spread of abnormal cells occurs.
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- Gamma-hydroxy-2-(fluoroalkylaminocarbonyl)-1-piperazinepentanamides and uses thereof
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γ-Hydroxy-2-(fluoroalkylaminocarbonyl)-1-piperazinepentanamide compounds are inhibitors of HIV protease and inhibitors of HIV replication. These compounds are useful in the prevention or treatment of infection by HV and the treatment of AIDS, either as compounds, pharmaceutically acceptable salts, pharmaceutical composition ingredients, whether or not in combination with other antivirals, immunomodulators, antibiotics or vaccines. Methods of treating AIDS and methods of preventing or treating infection by HIV are also described. These compounds are effective against HIV viral mutants which are resistant to HIV protease inhibitors currently used for treating AIDS and HIV infection.
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Page/Page column 174-175
(2010/01/31)
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- A new simple route to furanic ketones; preparation of elsholtzione naginata ketone and perilla ketone
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Copper- or iron-catalyzed acylation of organomanganese reagents allows to obtain 3- and 2-acylfurans in high yields. Elsholtzione, naginata ketone and perilla ketone have been prepared according to this procedure.
- Cahiez,Chavant,Metais
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p. 5245 - 5248
(2007/10/02)
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- Dihydroxyheptanoic acids containing an oxabicycloheptane nucleus useful as antihypercholesterolemic agents
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Dihydroxyheptonic acids containing an oxabicycloheptane nucleus are provided which have the structure STR1 including all stereoisomers thereof, wherein Z is STR2 and X, R1, R2 and R3 are as defined herein.
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- VOLATILE CONSTITUENTS OF CLAUSENA WILLDENOVII: STRUCTURES OF THE FURANOTERPENES α-CLAUSENAN, DICLAUSENAN A AND DICLAUSENAN B
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Four furanoid terpenic compounds, α-clausenan, rosefuran (γ-clausenan) and diclausenans A and B, were isolated from the essential oil of the leaves of Clausena willdenovii.Their structures were determined by chemical and spectral data.The occurence of a high concentration of rosefuran is noteworthy.Selenium dioxide oxidation of diclausenan gave an unusual product, identified as an epoxy-dicarbonyl compound. - Keywords: Clausena willdenovii; Rutaceae; furanoterpenes; α-clausenan; γ-clausenan (rosefuran); diclausenans A and B.
- Subba Rao, G. S. R.,Ravindranath, Bhagavatula,Sashi Kumar, V. P.
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p. 399 - 402
(2007/10/02)
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