- Total Synthesis of (±)-Aspergilline A
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The total synthesis of (±)-aspergilline A (1) is described. Key features of the synthesis include pyrrolinone formation via reaction of an intermediate propargyl amine with a methyl malonyl chloride derived ammonium enolate and a formal [3+2] cycloaddition between an imidate and cyclopropenone.
- Nakhla, Mina C.,Wood, John L.
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- Synthesis of 1,2-Dihydro-Substituted Aniline Analogues Involving N -Phenyl-3-aza-Cope Rearrangement Using a Metal-Free Catalytic Approach
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An efficient metal-free domino reaction leading to structural/electronically divergent 1,2-dihydropyridines from easily accessible propargyl vinyl anilines via N-phenyl 3-aza-Cope sigmatropic rearrangement is reported with good to excellent yields using 1,2-dichlorobenzene as solvent under thermal conditions. Spirocyclic substitution is also tolerated under the present optimized conditions.
- Alduhaish, Osamah,Varala, Ravi,Adil, Syed Farooq,Khan, Mujeeb,Siddiqui, Mohammed Rafiq H.,Alwarthan, Abdulrhman,Alam, M. Mujahid
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- DIHYDROOROTATE DEHYDROGENASE INHIBITORS
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Disclosed are compounds, compositions and methods for treating diseases, disorders, or medical conditions that are affected by the modulation of DHODH. Such compounds are represented by Formula (I) as follows: wherein R1, R2, R3, R4, X, and Y are defined herein.
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Page/Page column 75; 92
(2020/10/28)
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- BTK Inhibitors and uses thereof
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The invention discloses a bruton's tyrosine kinase (BTK) inhibitor and use thereof. Specifically, the invention provides heteroaromatic compounds or stereoisomers, geometrical isomers, tautomers, racemates, nitrogen oxides, hydrates, solvates, metabolites and pharmaceutically acceptable salts or prodrugs thereof, and pharmaceutical compositions containing the heteroaromatic compounds; the invention also discloses use of the heteroaromatic compounds or the pharmaceutical compositions containing the heteroaromatic compounds in preparation of medicines; the medicines can be used for treating autoimmune diseases, inflammatory diseases or proliferative diseases.
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Paragraph 1225-1230
(2020/05/02)
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- Synthesis of Halogenated Cyclic Enamines from Cyclic N-2-En-4-ynyl-N-1-ynylamides and N-Propargyl-N-1-ynylamides via a Tandem Iron Halide Promoted N-to-C Shift-Aza-Prins Cyclization Sequence
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A facile and efficient N-to-C allyl shift-aza-Prins cyclization sequence of cyclic N-2-en-4-ynyl-N-1-ynylamides is promoted by iron(III) chloride, generating chloro-containing bridged bicyclic enamines in minutes and in high yields. This reaction involves an unprecedented formation of a ketenimine via Fe(III)-mediated N-to-C allyl rearrangement, followed by aza-Prins cyclization. This sequence can also be applied to the generation of brominated cyclobutenamine derivatives using Fe(III) bromide and N-propargyl-N-1-ynylamides. (Figure presented.).
- Lin, Hsin-Hui,Chiang, Tai-Ching,Wu, Rong-Xuan,Chang, Yi-Mei,Wang, Hao-Wen,Liu, Ssu-Ting,Yeh, Ming-Chang P.
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supporting information
(2019/02/07)
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- SUBSTITUTED 5-CYANOINDOLE COMPOUNDS AND USES THEREOF
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A compound of Formula (I), or a pharmaceutically acceptable salt thereof, is provided that has been shown to be useful for the treatment of lysine (K)-specific demethylase 1A (LSD1) - mediated diseases or disorders, Formula (I), wherein R1, R2, R3, R4, and R5 are as defined herein.
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Paragraph 00249
(2019/01/10)
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- Robust Silver(I) Catalyst for the Carboxylative Cyclization of Propargylic Alcohols with Carbon Dioxide under Ambient Conditions
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Inspired by the bulkier bis(triphenylphosphine)-silver cation-induced mechanism of propargylic alcohols and carbon dioxide through the alkyl carbonate intermediate, a robust dual-component catalytic system consisting of silver acetate and tetraheptylammonium bromide was rationally developed for the synthesis of α-methylene cyclic carbonates under ambient conditions without employing any additional organic base and ligand. This is one of the most effective catalysts reported to date for this conversion, with a very high turnover number of up to 6024, probably due to the synergistic effect of Lewis basic and Lewis acidic species for the activation of both propargylic alcohol and carbon dioxide by the formation of the alkyl carbonate with a bulkier counterion. Notably, this catalyst also worked well for the carboxylative cyclization of propargylic amines with carbon dioxide with the highest turnover number of 544.
- Song, Qing-Wen,He, Liang-Nian
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supporting information
p. 1251 - 1258
(2016/04/26)
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- Palladium-Catalyzed [2+1] Cycloadditions Affording Vinylidenecyclopropanes as Precursors of 7-Membered Carbocycles
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Palladium(II) acetate in association with secondary phosphine oxides provides an efficient catalytic system for [2+1] cycloadditions starting from oxanorbornene derivatives and tertiary propargyl esters giving rise to vinylidenecyclopropanes. This reaction is specific to bidentate phosphinito-phosphinous acid ligands generated from secondary phosphine oxides. The [2+1] cycloaddition was found broad in scope with a high tolerance to various functional groups. Moreover, vinylidenecyclopropanes were straightforwardly converted into oxabicyclo[3.2.1]oct-2-ene derivatives through a palladium-catalyzed ring-expansion. Finally, the oxa bridge cleavage of oxatricyclic compounds yields functionalized 7-membered carbocycles.
- Lepronier, Aymeric,Achard, Thierry,Giordano, Laurent,Tenaglia, Alphonse,Buono, Gerard,Clavier, Herve
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supporting information
p. 631 - 642
(2016/02/27)
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- Convenient synthesis of allenylphosphoryl compounds: Via Cu-catalysed couplings of P(O)H compounds with propargyl acetates
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A novel Cu-catalysed substitution reaction of propargyl acetates with P(O)H compounds is developed to afford allenylphosphoryl compounds via C-P bond coupling in high yields under mild conditions. A plausible mechanism involving the nucleophilic interception of the Cu-allenylidene intermediates is proposed.
- Shen, Ruwei,Luo, Bing,Yang, Jianlin,Zhang, Lixiong,Han, Li-Biao
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supporting information
p. 6451 - 6454
(2016/05/24)
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- Silver-catalyzed three-component reaction of propargylic amines, carbon dioxide, and N-iodosuccinimide for stereoselective preparation of (E)-iodovinyloxazolidinones
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The silver-catalyzed three-component reaction of propargylic amines, carbon dioxide, and N-iodosuccinimide for the stereoselective synthesis of (E)-iodovinyloxazolidinones was developed. The silver-catalytic system could be applied to various propargylic amines to afford the corresponding iodovinyloxazolidinones in high yields. The structure of the oxazolidinone was confirmed by X-ray structure analysis to be the Eisomer for the geometry of the exo-olefin. The silver-catalyzed cyclization and replacement of silver with the iodine group in the intermediate were thought to be crucial steps.
- Sekine, Kohei,Kobayashi, Ryo,Yamada, Tohru
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supporting information
p. 1407 - 1409
(2015/11/24)
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- Diastereo- and enantioselective propargylation of benzofuranones catalyzed by pybox-copper complex
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Diastereo- and enantioselective preparation of 2,2-disubstituted benzofuran-3(2H)-one has been realized by a pybox-copper catalyzed reaction between 2-substituted benzofuran-3(2H)-one and propargyl acetate. The utility of this method was demonstrated by further transformation of the terminal alkyne into a methyl ketone without loss of enantiomeric purity.
- Zhao, Long,Huang, Guanxin,Guo, Beibei,Xu, Lijun,Chen, Jie,Cao, Weiguo,Zhao, Gang,Wu, Xiaoyu
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supporting information
p. 5584 - 5587
(2015/02/19)
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- Gold-catalyzed cyclization of allenyl acetal derivatives
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The gold-catalyzed transformation of allenyl acetals into 5-alkylidenecyclopent-2-en-1-ones is described. The outcome of our deuterium labeling experiments supports a 1,4-hydride shift of the resulting allyl cationic intermediates because a complete deuterium transfer is observed. We tested the reaction on various acetal substrates bearing a propargyl acetate, giving 4-methoxy-5-alkylidenecyclopent-2-en-1-ones 4 via a degradation of the acetate group at the allyl cation intermediate.
- Vasu, Dhananjayan,Pawar, Samir Kundlik,Liu, Rai-Shung
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supporting information
p. 1751 - 1756
(2013/10/22)
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- Efficient acetylation of alcohols and phenols catalyzed by recyclable lithium bis(perfluoroalkylsulfonyl)imide
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An efficient acetylation of alcohols and phenols catalyzed by lithium bis(perfluoroalkylsulfonyl)-imide was developed. This acetylation features good yields, mild reaction condtions, and simple workup procedures. Furthermore, the catalyst bearing a long perfluoroalkyl chain is recoverable and readily reusable without losing any activity. Copyright
- Li, Guilong,Zhao, Gang
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p. 34 - 43,10
(2020/08/24)
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- Cyclization-carbonylation-cyclization coupling reactions of propargyl acetates and amides with palladium(II)-bisoxazoline catalysts
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Clever boxing: A cyclization-carbonylation-cyclization-coupling reaction of propargyl acetates 1 or amides 2 in the presence of a palladium(II)- bisoxazoline (box) catalyst afforded symmetrical ketones of types 3 and 4, respectively, containing two heterocyclic groups in moderate to excellent yields (see scheme; tfa=trifluoroacetate). Compounds 3 were converted into ketones containing two 3(2H)-furanone rings.
- Yasuhara, Sumie,Sasa, Makiko,Kusakabe, Taichi,Takayama, Hiroyuki,Kimura, Masayuki,Mochida, Tomoyuki,Kato, Keisuke
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supporting information; experimental part
p. 3912 - 3915
(2011/06/20)
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- An unprecedented Pd-catalyzed, water-promoted sequential oxidative aminocarbonylation-cyclocarbonylation process leading to 2-oxazolidinones
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An unprecedented, Pdl2-catalyzed, sequential oxidative aminocarbonylation-cyclocarbonylation process, leading to 2-oxazolidinone derivatives 3 in good to excellent yields starting from readily available α,α-disubstituted 2-ynylamines 1 and secondary amines 2, is reported. In the case of an α-monosubstituted substrate, the initially formed 2-oxazolidinone derivative underwent shift of the double bond to give a 3H-oxazol-2-one derivative in excellent isolated yield.
- Gabriele, Bartolo,Plastina, Pierluigi,Salerno, Giuseppe,Mancuso, Raffaella,Costa, Mirco
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p. 3319 - 3322
(2008/02/12)
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- Synthesis of N-propargylanabasine derivatives by the mannich reaction
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N-Propargylanabasine derivatives bearing various substituents at the carbon atom of the alkyne fragment were obtained by the reaction of anabasine hydrochloride with terminal alkynes and paraformaldehyde. The reaction proceeded with retention of the C(2) chiral center in anabasine fragment. The by-products of the reaction, including 1,3-diacetylene (the products of dimerization of alkynes) and conjugated vinylacetylenes (the rearrangement products of the Mannich adducts) were isolated and characterized.
- Mavrov,Zlotin
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p. 1637 - 1647
(2008/09/18)
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- Zirconiuni(IV) chloride as a new, highly efficient, and reusable catalyst for acetylation of phenols, thiols, amines, and alcohols under solvent-free conditions
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Zirconium(IV) chloride has been found to be a new, highly efficient, and reusable catalyst for acetylation of structurally diverse phenols, thiols, amines, and alcohols under solvent-free condtions. Acetylation of sterically hindered and electron deficient phenols is achieved in excellent yields with stoichiometric amounts of Ac2O at room temperature. Acid-sensitive alcohols undergo acetylation with excellent chemoselectivity without competitive side reactions such as dehydration or rearrangement. The mild Lewis acid property of the catalyst enables the acetylation to be carried out with optically active substrates without any detrimental effect on the optical purity.
- Chakraborti, Asit K.,Gulhane, Rajesh
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p. 627 - 630
(2007/10/03)
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- On the palladium(II)-catalysed oxidative rearrangement of propargylic acetates
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The catalytic transformation of propargylic acetates into the corresponding α-acetoxyenones in the presence of palladium(II) chloride is described. Water is a necessary component in this unusual oxidative rearrangement.
- Bartels,Mahrwald,Mueller
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p. 483 - 485
(2007/10/03)
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- Fluoroboric acid adsorbed on silica gel as a new and efficient catalyst for acylation of phenols, thiols, alcohols, and amines
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Fluoroboric acid supported on silica gel efficiently catalyzes acylation of structurally diverse phenols, alcohols, thiols, and amines under solvent free conditions. Acid-sensitive alcohols are smoothly acylated without competitive side reactions.
- Chakraborti, Asit K.,Gulhane, Rajesh
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p. 3521 - 3525
(2007/10/03)
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- Indium(III) chloride as a new, highly efficient, and versatile catalyst for acylation of phenols, thiols, alcohols, and amines
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Indium(III) chloride efficiently catalyses the acylation of structurally diverse phenols, alcohols, thiols, and amines under solvent free conditions. Acid sensitive alcohols are smoothly acylated without competitive side reactions. Acylation of 2-hydroxynaphthalene is carried out with carboxylic acids adopting the mixed anhydride protocol using trifluoroacetic anhydride.
- Chakraborti, Asit K.,Gulhane, Rajesh
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p. 6749 - 6753
(2007/10/03)
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- Electrostatic catalysis by ionic aggregates: Scope and limitations of Mg(ClO4)2 as acylation catalyst
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Alkali and alkaline earth metal perchlorates exhibit electrostatic catalysis in the activation of anhydrides for the acylation reaction. Perchlorates with higher values of the charge-size function of the metal ion exhibit better catalytic activity following the order Mg(ClO4) 2>Ba(ClO4)2>LiClO4. Acylation of structurally diverse phenols, thiols, alcohols, and amines have been carried out with stoichiometric amounts of anhydride at room temperature under solvent free conditions in the presence of catalytic amount of Mg(ClO4) 2. Sterically hindered and electron deficient phenols are efficiently acylated. Acylation with sterically hindered anhydrides such as iso-butyric, pivalic, and benzoic anhydrides are carried out with phenols and alcohols in excellent yields. Acid-sensitive alcohols are acylated in excellent yields without any competitive side reactions.
- Chakraborti, Asit K.,Sharma, Lalima,Gulhane, Rajesh,Shivani
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p. 7661 - 7668
(2007/10/03)
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- Perchloric acid adsorbed on silica gel as a new, highly efficient, and versatile catalyst for acetylation of phenols, thiols, alcohols, and amines
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Perchloric acid adsorbed on silica gel efficiently catalyses acetylation of structurally diverse phenols, alcohols, thiols, and amines under solvent free conditions.
- Chakraborti, Asit K.,Gulhane, Rajesh
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p. 1896 - 1897
(2007/10/03)
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- Zn(ClO4)2·6H2O as a Powerful Catalyst for a Practical Acylation of Alcohols with Acid Anhydrides
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A new protocol for the acylation of alcohols with anhydrides in the presence of Zn(ClO4)2·6H2O as the catalyst is reported. The activity of Zn(ClO4)2· 6H2O has been proven to be superior to that exerted by dry Mg(ClO4)2 and by metal triflates. Its efficiency allows reactions between poorly reactive substrates, such as sterically hindered tertiary alcohols and aromatic anhydrides, All of the reactions were carried out at a 1:1.05 alcohol/anhydride ratio. These conditions are extremely convenient from a practical and economic point of view, since they avoid wasting reagents and allow a simple workup procedure. The catalytic action of Zn(ClO4)2·6H2O is so specific for the activation of the anhydrides, that acid-sensitive functionalities and the stereochemical configuration of the starting materials remain unaltered in the esterification process. In all cases, the acylated products are quantitatively obtained in pure form. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
- Bartoli, Giuseppe,Bosco, Marcella,Dalpozzo, Renato,Marcantoni, Enrico,Massaccesi, Massimo,Sambri, Letizia
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p. 4611 - 4617
(2007/10/03)
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- Zeolite HSZ-360 as a new reusable catalyst for the direct acetylation of alcohols and phenols under solventless conditions
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Alcohols and phenols were efficiently acylated with acetic anhydride without solvent over zeolite HSZ-360. The catalyst can be reused with no activity loss.
- Ballini, Roberto,Bosica, Giovanna,Carloni, Silvia,Ciaralli, Lara,Maggi, Raimondo,Sartori, Giovanni
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p. 6049 - 6052
(2007/10/03)
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- Synthesis and biological activity of a novel series of nonsteroidal, peripherally selective androgen receptor antagonists derived from 1,2- dihydropyridono[5,6-g]quinolines
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A new nonsteroidal antiandrogenic pharmacophore has been discovered using cell-based cotransfection assays with human androgen receptor (hAR). This series of AR antagonists is structurally characterized by a linear tricyclic 1,2-dihydropyridono[5,6-g]quinoline core. Analogues inhibit AR- mediated reporter gene expression and bind to AR as potently as or better than any known AR antagonists. Several analogues also showed excellent in vivo activity in classic rodent models of AR antagonism, inhibiting growth of rat ventral prostate and seminal vesicles, without accompanying increases in serum gonadotropin and testosterone levels, as is seen with other AR antagonists. Investigations of structure - activity relationships surrounding this pharmacophore resulted in molecules with complete specificity for AR, antagonist activity on an AR mutant commonly observed in prostate cancer patients, and improved in vivo efficacy. Molecules based on this series of compounds have the potential to provide unique and effective clinical opportunities for treatment of prostate cancer and other androgen-dependent diseases.
- Hamann, Lawrence G.,Higuchi, Robert I.,Zhi, Lin,Edwards, James P.,Wang, Xiao-Ning,Marschke, Keith B.,Kong, James W.,Farmer, Luc J.,Jones, Todd K.
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p. 623 - 639
(2007/10/03)
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- Unsaturated spiro-γ-lactone formation by the dissociative reduction of bromoacetates
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Unsaturated spiro-γ-butyrolactones can be prepared in good yields from bromoacetate precursors by a simple route that requires only 2-propanol as solvent and free radical initiation.
- Kolt,Griller,Wayner
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p. 7539 - 7540
(2007/10/02)
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- Diels-Alder Route to Potential Trichothecene Precursors
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2-Methyl-3-yn-2-ol (9) is efficiently converted into 6-formyl-3,6-dimethylcyclohex-2-enyl acetate (4b) and into 6-acetyl-3,6-dimethylcyclohex-2-enyl acetate (4c) via highly regio- and stereo-selective Diels-Alder cycloadditions of 3-methylbuta-1,3-dienyl acetate (2b).The cycloadduct (4b) is converted by base into 4a,5,6,8a-tetrahydro-4a,7-dimethylcoumarin (13b), whilst the cycloadduct (4c) yields 2,3,4a,5,6,8a-hexahydro-2-hydroxy-2,4a,7-trimethylchroman-4-one (15), the structure of which was confirmed by X-ray analysis.Both (13b) and (15) possess a number of structural features of the trichothecenes and may be of value in their total synthesis.
- Banks, Robert E.,Miller, Allen J.,Nunn, John M.,Stanley, Philip,Weakley, Timothy J. R.,Ullah, Zakir
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p. 1096 - 1102
(2007/10/02)
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