- Mono-Gold(I)-Catalyzed Enantioselective Intermolecular Reaction of Ynones with Styrenes: Tandem Diels–Alder and Ene Sequence
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Gold-catalyzed intermolecular reaction leading to dihydronaphthalene derivatives in one pot from two equivalents of ynones with respect to styrene is uncovered. The [4+2] Diels–Alder cycloaddition of ynones and styrenes is catalyzed by a mono-gold(I) complex and the conjugated acid to provide an unstable 3,8a-dihydronaphthalene to subsequently undergo an intermolecular ene-type reaction with the π-activated ynone to afford multi-component coupling dihydronaphthalene products. Linear relationships between chiral ligand-gold complexes and chiral dihydronaphthalene products proves mono-gold catalysis that triggers an asymmetric tandem Diels–Alder and ene reaction sequence.
- Nanko, Masaki,Inaba, Yuya,Sekine, Keisuke,Mikami, Koichi
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Read Online
- Troponoids can inhibit growth of the human fungal pathogen Cryptococcus neoformans
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Cryptococcus neoformans is a pathogen that is common in immunosuppressed patients. It can be treated with amphotericin B and fluconazole, but the mortality rate remains 15 to 30%. Thus, novel and more effective anticryptococcal therapies are needed. The troponoids are based on natural products isolated from western red cedar, and have a broad range of antimicrobial activities. Extracts of western red cedar inhibit the growth of several fungal species, but neither western red cedar extracts nor troponoid derivatives have been tested against C. neoformans. We screened 56 troponoids for their ability to inhibit C. neoformans growth and to assess whether they may be attractive candidates for development into anticryptococcal drugs. We determined MICs at which the compounds inhibited 80% of cryptococcal growth relative to vehicle-treated controls and identified 12 compounds with MICs ranging from 0.2 to 15 μM. We screened compounds with MICs of ≤20 μM for cytotoxicity in liver hepatoma cells. Fifty percent cytotoxicity values (CC50s) ranged from 4 to >100 μM. The therapeutic indexes (TI, CC50/MIC) for most of the troponoids were fairly low, with most being 8, including a tropone with a TI of >300. These tropones are fungicidal and are not antagonistic when used in combination with fluconazole or amphotericin B. Inhibition by these two tropones remains unchanged under conditions favoring cryptococcal capsule formation. These data support the hypothesis that troponoids may be a productive scaffold for the development of novel anticryptococcal therapies.
- Donlin, Maureen J.,Zunica, Anthony,Lipnicky, Ashlyn,Garimallaprabhakaran, Aswin K.,Berkowitz, Alex J.,Grigoryan, Alexandre,Meyers, Marvin J.,Tavis, John E.,Murellic, Ryan P.
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Read Online
- Metabolically stable vanillin derivatives for the treatment of hypoxia
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Vanillin derivative compounds that bind covalently with hemoglobin are provided. Methods of treating sickle cell disease and other hypoxia-related disorders by administering such compounds are also provided.
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- Enantioselective [3 + 2] annulation of 4-isothiocyanato pyrazolones and alkynyl ketones under organocatalysis
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An asymmetric [3 + 2] annulation reaction of 4-isothiocyanato pyrazolones with alkynyl ketones in the presence of an organic catalyst derived from a cinchona alkaloid under mild conditions is realized. This protocol provides unprecedented expeditious access to a wide range of optically active spiro[pyrroline-pyrazolones] with various electronic properties in high yields with good to excellent enantioselectivities.
- Wang, Wenyao,Wei, Shiqiang,Bao, Xiaoze,Nawaz, Shah,Qu, Jingping,Wang, Baomin
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p. 1145 - 1154
(2021/02/16)
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- An investigation of structure‐activity relationships of azolylacryloyl derivatives yielded potent and long‐acting hemoglobin modulators for reversing erythrocyte sickling
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Aromatic aldehydes that bind to sickle hemoglobin (HbS) to increase the protein oxygen affinity and/or directly inhibit HbS polymer formation to prevent the pathological hypoxia‐induced HbS polymerization and the subsequent erythrocyte sickling have for s
- Abdulmalik, Osheiza,El‐araby, Moustafa E.,Ghatge, Mohini S.,Muhammad, Yosra A.,Omar, Abdelsattar M.,Paredes, Steven D.,Safo, Martin K.
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- Palladium-Catalyzed Oxidative C≡C Triple Bond Cleavage of 2-Alkynyl Carbonyl Compounds Toward 1,2-Dicarbonyl Compounds?
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A new, general palladium-catalyzed oxidative strategy for the cleavage of the C≡C triple bond is presented. By employing PdCl2, CuBr2, TEMPO and air as the catalytic system and H2O as the carbonyl oxygen atom source, a wide range of 2-alkynyl carbonyl compounds, including 1,3-disubstituted prop-2-yn-1-ones, propiolamides and propiolates, lost an alkynyl carbon to access various 1,2-dicarbonyl compounds, e.g., 1,2-diones, 2-keto amides and 2-keto esters, through Wacker oxidation, intramolecular cyclization and C—C bond cleavage cascades.
- Hu, Ming,Li, Jin-Heng,Luo, Mu-Jia,Zhou, Ming-Bo
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supporting information
p. 553 - 558
(2020/04/20)
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- Laccase-mediated Oxidations of Propargylic Alcohols. Application in the Deracemization of 1-arylprop-2-yn-1-ols in Combination with Alcohol Dehydrogenases
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The catalytic system composed by the laccase from Trametes versicolor and the oxy-radical TEMPO has been successfully applied in the sustainable oxidation of fourteen propargylic alcohols. The corresponding propargylic ketones were obtained in most cases in quantitative conversions (87–>99 % yield), demonstrating the efficiency of the chemoenzymatic methodology in comparison with traditional chemical oxidants, which usually lead to problems associated with the formation of by-products. Also, the stereoselective reduction of propargylic ketones was studied using alcohol dehydrogenases such as the one from Ralstonia species overexpressed in E. coli or the commercially available evo-1.1.200, allowing the access to both alcohol enantiomers mostly with complete conversions and variable selectivities depending on the aromatic pattern substitution (97–>99 % ee). To demonstrate the compatibility of the laccase-mediated oxidation and the alcohol dehydrogenase-catalyzed bioreduction, a deracemization strategy starting from the racemic compounds was developed through a sequential one-pot two-step process, obtaining a selection of (S)- or (R)-1-arylprop-2-yn-1-ols with excellent yields (>98 %) and selectivities (>98 % ee) depending on the alcohol dehydrogenase employed.
- González-Granda, Sergio,Méndez-Sánchez, Daniel,Lavandera, Iván,Gotor-Fernández, Vicente
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p. 520 - 527
(2019/11/16)
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- A sustainable access to ynones through laccase/TEMPO-catalyzed metal- and halogen-free aerobic oxidation of propargylic alcohols in aqueous medium
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Tuning laccase/TEMPO-catalyzed aerobic oxidation of secondary propargylic alcohols in aqueous media was accomplished in order to efficiently synthesize ynones. This study led to the formulation of an effective and sustainable catalytic method for the preparation of mono- and bis-substituted ynones compared with traditional oxidative methods.
- Silva, Alana B.V.,Silva, Emmanuel D.,dos Santos, Alcindo A.,Princival, Jefferson L.
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- Relay Catalysis to Synthesize β-Substituted Enones: Organocatalytic Substitution of Vinylogous Esters and Amides with Organoboronates
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Organocatalysis was shown to facilitate conjugate additions to vinylogous esters and amides for the first time. Subsequent elimination of a β-alcohol or amine provided π-conjugated β-substituted enones. Remarkably, nucleophile addition to the electron-rich vinylogous substrates is more rapid than classical enones, forming monosubstituted products. A doubly organocatalytic (organic diol and methyl aniline) conjugate addition synthesized the products directly from alkynyl ketones. Both of these catalytic transformations are orthogonal to transition metal catalysis, allowing for good yields, easily accessible or commercially available reagents, high selectivity, reagent recovery and recyclability, facile scalability, and exceptional functional group tolerance.
- Sundstrom, Sasha,Nguyen, Thien S.,May, Jeremy A.
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p. 1355 - 1359
(2020/02/13)
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- Covalent Adaptable Networks with Tunable Exchange Rates Based on Reversible Thiol–yne Cross-Linking
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The design of covalent adaptable networks (CANs) relies on the ability to trigger the rearrangement of bonds within a polymer network. Simple activated alkynes are now used as versatile reversible cross-linkers for thiols. The click-like thiol–yne cross-linking reaction readily enables network synthesis from polythiols through a double Michael addition with a reversible and tunable second addition step. The resulting thioacetal cross-linking moieties are robust but dynamic linkages. A series of different activated alkynes have been synthesized and systematically probed for their ability to produce dynamic thioacetal linkages, both in kinetic studies of small molecule models, as well as in stress relaxation and creep measurements on thiol–yne-based CANs. The results are further rationalized by DFT calculations, showing that the bond exchange rates can be significantly influenced by the choice of the activated alkyne cross-linker.
- Du Prez, Filip E.,Guerre, Marc,Maes, Diederick,Unal, Kamil,Van Herck, Niels,Winne, Johan M.
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p. 3609 - 3617
(2020/02/04)
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- Cracking under internal pressure: Photodynamic behavior of vinyl azide crystals through N2release
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When exposed to UV light, single crystals of the vinyl azides 3- azido-1-phenylpropenone (1a), 3-azido-1-(4-methoxyphenyl)propenone (1b), and 3-azido-1-(4-chlorophenyl)propenone (1c) exhibit dramatic mechanical effects by cracking or bending with the release of N2. Mechanistic studies using laser flash photolysis, supported by quantum mechanical calculations, show that each of the vinyl azides degrades through a vinylnitrene intermediate. However, despite having very similar crystal packing motifs, the three compounds exhibit distinct photomechanical responses in bulk crystals. While the crystals of 1a delaminate and release gaseous N2 indiscriminately under paraffin oil, the crystals of 1b and 1c visibly expand, bend, and fracture, mainly along specific crystallographic faces, before releasing N2. The photochemical analysis suggests that the observed expansion is due to internal pressure exerted by the gaseous product in the crystal lattices of these materials. Lattice energy calculations, supported by nanoindentation experiments, show significant differences in the respective lattice energies. The calculations identify critical features in the crystal structures of 1b and 1c where elastic energy accumulates during gas release, which correspond to the direction of the observed cracks. This study highlights the hitherto untapped potential of photochemical gas release to elicit a photomechanical response and motility of photoreactive molecular crystals.
- Shields, Dylan J.,Karothu, Durga Prasad,Sambath, Karthik,Ranaweera, Ranaweera A. A. Upul,Schramm, Stefan,Duncan, Alexander,Duncan, Benjamin,Krause, Jeanette A.,Gudmundsdottir, Anna D.,Naumov, Pan?e
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p. 18565 - 18575
(2020/12/01)
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- Copper-catalyzed method for preparing aldehyde or ketone compound by oxidizing alcohol with oxygen as oxidizing agent and application
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The invention discloses a copper-catalyzed method for preparing an aldehyde or ketone compound by oxidizing alcohol with oxygen as an oxidizing agent. Reaction is performed in an organic solvent for 4-48 hours at room temperature by using copper salt and nitroxide free radicals as catalysts and oxygen or air as an oxidizing agent to efficiently oxidize an alcohol compound into the corresponding aldehyde or ketone compound. The method is simple to operate, free of chlorides corrosive to equipment, available in raw materials and reagents, mild in reaction conditions, wide in substrate universality, good in functional group compatibility, convenient in separation and purification, environmentally friendly in the whole process and free of pollution, and is a method suitable for industrial production.
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Paragraph 0028-0030; 0037-0039
(2020/08/18)
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- The Impact of Crystal Packing and Aurophilic Interactions on the Luminescence Properties in Polymorphs and Solvate of Aroylacetylide–Gold(I) Complexes
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The influence of the chemical substitution, crystal packing, and aurophilic interactions of the gold(I) acetylide complexes of the type (ArCOC≡C)nAuPEt3 (n=1,2) on their luminescent properties were examined. All described complexes undergo ligand scrambling in solution, which results in the formation of stable, easily isolated crystals that contain [ArCO(C≡C)n]2Au?(Et3P)2Au+ homoleptic species. In particular, we observed that the (benzoylacetylide)gold(I) complex yields three crystal forms with strikingly different luminescence properties. We monitored the conversion pathway for these forms: an orange luminescent form of homoleptic complex upon drying undergoes spontaneous transformation to bright green fluorescent form and finally to the weakly blue emissive one. In addition, we report a rare example of a helical arrangement of Au?Au?Au chains that are observed for the first time in acetylide gold(I) complexes in the case of heteroleptic (benzoylacetylide)gold(I) complex. This is a very rare case in which crystal structures and ensuing electronic properties of the heteroleptic and AuI complexes could be directly compared.
- G?odek, Marta,Pawl?dzio, Sylwia,Makal, Anna,Pla?uk, Damian
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p. 13131 - 13145
(2019/09/06)
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- A novel synthesis of N-hydroxy-3-aroylindoles and 3-aroylindoles
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A straightforward indole synthesis via annulation of C-nitrosoaromatics with conjugated terminal alkynones was realised achieving a simple, highly regioselective, atom- and step economical access to 3-aroylindoles in moderate to good yields. Further functionalizations of indole scaffolds were investigated and an easy way to JWH-018, a synthetic cannabinoid, was achieved.
- Ieronimo, Gabriella,Palmisano, Giovanni,Maspero, Angelo,Marzorati, Alessandro,Scapinello, Luca,Masciocchi, Norberto,Cravotto, Giancarlo,Barge, Alessandro,Simonetti, Marco,Ameta, Keshav Lalit,Nicholas, Kenneth M.,Penoni, Andrea
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p. 6853 - 6859
(2018/10/20)
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- Gem-Digold Acetylide Complexes for Catalytic Intermolecular [4 + 2] Cycloaddition: Having Two Gold Centers Is Better for Asymmetric Catalysis
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Gold(I)-catalyzed highly enantioselective intermolecular [4 + 2] cycloaddition is shown with ynones and cyclohexadiene. Various bicyclo[2.2.2]octadiene derivatives are produced in high yields (up to 99%) with good enantioselectivity (up to 96% ee). Key to the success is generation of the gem-digold terminal alkyne as a catalytic on-cycle species. As proof of the gem-digold catalysis, a positive nonlinear effect is clarified between the ee's of the ligand and the cycloadduct.
- Nanko, Masaki,Shibuya, Satoru,Inaba, Yuya,Ono, Soichiro,Ito, Shigekazu,Mikami, Koichi
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p. 7353 - 7357
(2018/10/15)
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- 2,4,6-TRIALKOXYSTRYL ARYL SULFONES, SULFONAMIDES AND CARBOXAMIDES, AND METHODS OF PREPARATION AND USE
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Compounds according to Formula (I) are provided and salts thereof, wherein R1, R2, R33, R4, R5, R6, R13, A, X and Y are as defined herein. Methods for preparing compounds of Form
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Page/Page column 58; 59
(2017/02/28)
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- Styrene as 4π-Component in Zn(II)-Catalyzed Intermolecular Diels-Alder/Ene Tandem Reaction
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A mild Zn-catalyzed intermolecular Diels-Alder/ene tandem reaction with styrene as a 4π-component is reported. A variety of dihydronaphthalene products could be prepared in moderate to good yields. Moreover, a combination of DFT calculations and experiments was performed to further understand the mechanism of this unique tandem reaction.
- Zheng, Min,Wu, Feng,Chen, Kai,Zhu, Shifa
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p. 3554 - 3557
(2016/08/16)
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- Synthesis and evaluation of novel fluorinated pyrazolo-1,2,3-triazole hybrids as antimycobacterial agents
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A library of novel 3-trifluoromethyl pyrazolo-1,2,3-triazole hybrids (5-7) were accomplished starting from 5-phenyl-3-(trifluoromethyl)-1H-pyrazol-4-amine (1) via key intermediate 2-azido-N-(5-phenyl-3-(trifluoromethyl)-1H-pyrazol-4-yl)acetamide (3) throu
- Emmadi, Narender Reddy,Bingi, Chiranjeevi,Kotapalli, Sudha Sravanti,Ummanni, Ramesh,Nanubolu, Jagadeesh Babu,Atmakur, Krishnaiah
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p. 2918 - 2922
(2015/06/22)
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- AZOLE DERIVATIVE
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The present invention provides agents for treating or preventing diseases such as mood disorder, anxiety disorder, schizophrenia, Alzheimer's disease, Parkinson's disease, Huntington's chorea, eating disorder, hypertension, gastrointestinal disease, drug addiction, epilepsy, cerebral infarction, cerebral ischemia, cerebral edema, head injury, inflammation, immune-related disease, alopecia, and so forth. Specifically, the invention provides azole derivatives represented by general formula (I), or pharmaceutically acceptable salts thereof that have an antagonistic action against the arginine-vasopressin (AVP) V1b receptor:
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Paragraph 0389; 0390
(2014/09/17)
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- Direct synthesis of pyrroles via 1,3-dipolar cycloaddition of azomethine ylides with ynones
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A direct and facile synthesis of multi-substituted pyrroles via AgOAc-catalyzed 1,3-dipolar cycloaddition of azomethine ylides with ynones is developed, providing the corresponding adducts in moderate to high yields (up to 89%).
- Wang, Zheng,Shi, Ying,Luo, Xiaoyan,Han, De-Man,Deng, Wei-Ping
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p. 1742 - 1745
(2013/06/27)
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- Parallel synthesis of "Click" chalcones as antitubulin agents
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It has been shown that some chalcones are able to inhibit tubulin polymerization, giving cytotoxicity and destruction of tumoral vasculature. A library of 180 novel chalcone analogs has been synthesized via click chemistry and screened for their cytotoxic
- Utsintong, Maleeruk,Massarotti, Alberto,Caldarelli, Antonio,Theeramunkong, Sewan
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p. 510 - 516
(2013/07/28)
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- Oxidation of propargylic alcohols with a 2-quinoxalinol salen copper(II) complex and tert-butyl hydroperoxide
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The copper(II) complex of 2-quinoxalinol salen (salqu) is an efficient catalyst for the selective oxidation of propargylic alcohols to yield the corresponding α,β-acetylenic carbonyl compounds when used in combination with the oxidant tert-butyl hydroperoxide (TBHP). Excellent yields (up to 99 %) are achieved for a variety of propargylic alcohols within 1 h of reaction time. The (salqu)copper(II) complex with TBHP can be used with propargylic alcohols that contain alkyl groups in the α-position, which can be difficult to oxidize selectively with other commonly available methods. By using this catalytic protocol, excellent selectivity was also achieved for the oxidation of propargylic alcohols over that of isolated hydroxy groups, triple bonds, or propargylic methylene groups. The 2-quinoxalinol salen copper(II) complex is an efficient catalyst when used with tert-butyl hydroperoxide for the oxidation of propargylic alcohols to yield the corresponding carbonyl compounds. This catalytic system provides excellent selectivity for the reaction with propargylic alcohols, and high yields (up to 99 %) are achieved within 1 h and with 1 mol-% of catalyst loading. Copyright
- Weerasiri, Kushan C.,Gorden, Anne E. V.
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p. 1546 - 1550
(2013/04/10)
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- Palladacycle-catalyzed reaction of bicyclic alkenes with terminal ynones: Regiospecific synthesis of polysubstituted furans
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A new synthetic strategy to access polysubstituted furans regiospecifically has been developed using simple bicyclic alkenes and terminal ynones as starting materials with palladacycles as unique active catalysts. A rational mechanism has also been proposed. This reaction features mild reaction conditions, easily available starting materials and palladacycle catalysts, a wide substrate scope, and high regiospecificity.
- Ge, Guang-Cun,Mo, Dong-Liang,Ding, Chang-Hua,Dai, Li-Xin,Hou, Xue-Long
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p. 5756 - 5759
(2013/01/15)
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- Development of manganese(VI) oxidising agents soluble in organic solvents
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Two manganate(VI) reagents have been prepared from permanganate salts that show excellent oxidising properties in common organic solvents. Georg Thieme Verlag Stuttgart · New York.
- Ellis, Rhys,Lee, Kee-Han,Ainsworth, Matthew,Kerr, Alexander,Viseux, Eddy M. E.
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experimental part
p. 1371 - 1373
(2012/06/30)
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- (Z)-1-Aryl-3-arylamino-2-propen-1-ones, highly active stimulators of tubulin polymerization: Synthesis, structure-activity relationship (SAR), tubulin polymerization, and cell growth inhibition studies
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Tubulin, the major structural component of microtubules, is a target for the development of anticancer agents. A series of (Z)-1-aryl-3-arylamino-2- propen-1-one (10) were synthesized and evaluated for antiproliferative activity in cell-based assay. The most active compound (Z)-1-(2-bromo-3,4,5- trimethoxyphenyl)-3-(3-hydroxy-4-methoxyphenylamino)prop-2-en-1-one (10ae) was tested in 20 tumor cell lines including multidrug resistant phenotype and was found to induce apoptosis in all these cell lines with similar GI50 values. Flow cytometry studies showed that 10ae arrested the cells in G2/M phase of cell cycle. In addition to G2/M block, these compounds caused microtubule stabilization like paclitaxel and induced apoptosis via activation of the caspase family. The observations made in this investigation demonstrate that (Z)-1-Aryl-3-arylamino-2-propen-1-one (10) represents a new class of microtubule-stabilizing agents.
- Reddy, M. V. Ramana,Akula, Balaiah,Cosenza, Stephen C.,Lee, Clement M.,Mallireddigari, Muralidhar R.,Pallela, Venkat R.,Subbaiah, D. R. C. Venkata,Udofa, Andrew,Reddy, E. Premkumar
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experimental part
p. 5174 - 5187
(2012/08/28)
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- The catalytic asymmetric 1,3-dipolar cycloaddition of ynones with azomethine ylides
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The first catalytic asymmetric 1,3-dipolar cycloaddition of electron-deficient carbon-carbon triple bonds with azomethine ylides has been established. This reaction provides an unprecedented approach to access novel 2,5-dihydropyrrole derivatives with potential bioactivities in perfect enantioselectivities of up to >99% ee.
- Shi, Feng,Luo, Shi-Wei,Tao, Zhong-Lin,He, Long,Yu, Jie,Tu, Shu-Jiang,Gong, Liu-Zhu
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p. 4680 - 4683
(2011/11/06)
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- Three-component reaction for the C2-functionalization of 1-substituted imidazoles with acetylenic ketones and isocyanates
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An efficient method for the direct C2-amidation of 1-substituted imidazoles with acetylenic ketones and isocyanates is reported. This three-component procedure has the advantages of catalyst-free, operational simplicity, mild reaction conditions, and good to excellent yields.
- Shen, Yang,Cai, Shuying,He, Chi,Lin, Xufeng,Lu, Ping,Wang, Yanguang
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p. 8338 - 8342
(2011/11/12)
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- Bohlmann-Rahtz cyclodehydration of aminodienones to pyridines using N-iodosuccinimide
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Cyclodehydration of Bohlmann-Rahtz aminodienone intermediates using N-iodosuccinimide as a Lewis acid proceeds at low temperature under very mild conditions to give the corresponding 2, 3,6-trisubstituted pyridines in high yield and with total regiocontrol.
- Bagley, Mark C.,Glover, Christian
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experimental part
p. 3211 - 3227
(2010/09/04)
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- N-Vinylpyridinium tetrafluoroborate salts as reagents for the stereoselective and regioselective synthesis of symmetrical (2E,4E)-1,6-dioxo-2,4-dienes
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We had previously demonstrated the utility of N-vinylpyridinium tetrafluoroborate salts as novel electrophilic coupling partners in Pd(0)-catalyzed Suzuki cross-coupling reactions with aryl and vinyl boronic acids. We now report that these crystalline, air-stable, and non-hygroscopic salts are also useful reagents for the synthesis of symmetrical (2E,4E)-1,6-dioxo-2,4-dienes (diene diones), which in turn are valuable starting materials for the synthesis of various five-membered heterocycles. The optimization of reaction conditions and the scope and limitations of the reductive dimerization are discussed.
- Gao, Ge,Brown, Neil,Minatoya, Machiko,Buszek, Keith R.
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scheme or table
p. 6491 - 6494
(2009/04/06)
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- Synthesis of pyroglutamic acid derivatives via double michael reactions of alkynones
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In the presence of substoichiometric quantities of potassium tert-butoxide and an additional metal salt, amide-tethered diacids undergo double Michael reactions with alkynones to provide highly functionalized pyroglutamic acid derivatives. The metal salt was found to play an important role in improving the diastereoselectivities of the reactions.
- Scansetti, Myriam,Hu, Xiangping,McDermott, Benjamin P.,Lam, Hon Wai
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p. 2159 - 2162
(2008/02/02)
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- Straightforward synthesis of highly hydroxylated phloroglucinol-type 3-deoxyanthocyanidins
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Phloroglucinol-type 3-deoxyanthocyanidins were synthesized through the interaction between phloroglucinol derivatives and arylethynylketones in acetic acid in the presence of aqueous hexafluorophosphoric acid. This methodology was applied to achieve the synthesis of natural apigeninidin, luteolinidin and tricetanidin with high yields. Georg Thieme Verlag Stuttgart.
- Kueny-Stotz, Marie,Isorez, Géraldine,Chassaing, Stefan,Brouillard, Raymond
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p. 1067 - 1070
(2008/02/13)
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- Straightforward synthesis of highly hydroxylated phloroglucinol-type 3-deoxyanthocyanidins
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Phloroglucinol-type 3-deoxyanthocyanidins were synthesized through the interaction between phloroglucinol derivatives and arylethynylketones in acetic acid in the presence of aqueous hexafluorophosphoric acid. This methodology was applied to achieve the synthesis of natural apigeninidin, luteolinidin and tricetanidin with high yields. Georg Thieme Verlag Stuttgart.
- Kueny-Stotz, Marie,Isorez, Géraldine,Chassaing, Stefan,Brouillard, Raymond
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p. 1223 - 1226
(2008/02/07)
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- Rapid preparation of 3-deoxyanthocyanidins and novel dicationic derivatives: New insight into an old procedure
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Common 3-deoxyanthocyanidins and original dicationic flavylium- benzopyrylium derivatives are easily and efficiently synthesized through reactions between the corresponding phenols and aryl ethynyl ketones in the presence of aqueous hexafluorophosphoric acid. The mechanism of the reaction is discussed and two competitive pathways are consistent with our results. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
- Chassaing, Stefan,Kueny-Stotz, Marie,Isorez, Geraldine,Brouillard, Raymond
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p. 2438 - 2448
(2008/03/13)
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- Structural characterization of crystalline inclusion complexes formed from 1,3,5-triaroylbenzene derivatives - A new family of inclusion hosts
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A series of crystalline inclusion complexes formed from substituted 1,3,5-triaroylbenzene hosts and small molecule guests has been structurally characterized by X-ray crystallography. The new inclusion hosts examined do not possess functional groups capab
- Pigge, F. Christopher,Ghasedi, Fatemeh,Zheng, Zhanmiao,Rath, Nigam P.,Nichols, Gary,Chickos, James S.
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p. 2458 - 2464
(2007/10/03)
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- The Synthesis of Electron Donor-acceptor Substituted Pyrazoles
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A variety of 1,3- and 1,5-donor-acceptor substituted pyrazole derivatives have been synthesized by the cyclocondensation of α,β-ethynyl ketones with substituted phenyl hydrazines.The regioselectivity of the cyclization depends on the reaction conditions in a manner consistent with competitive 1,2- and 1,4-addition followed by ring closure. 1,4-disubstituted derivatives can be prepared from the corresponding 4-iodopyrazole using palladium catalyzed carbon-carbon bond forming reactions.The pyrazole chromophores are expected to show interesting nonlinear optical properties.
- Miller, R. D.,Reiser, O.
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p. 755 - 764
(2007/10/02)
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- The Photochemistry of α,β-Acetylenic Ketones. II. Formation of Furan Derivatives
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The phochemical reactions of α,β-acetylenic ketones have been examined.Irradiation of 1-p-substituted phenyl-2-propyn-1-ones 2-4 in primary alcohols gave 2,5-disubstituted furans 2a-4c.The formation of furans can be explained in terms of cyclization, foll
- Nishio, Takehiko,Nakata, Hiroyuki,Omote, Yoshimori
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p. 1011 - 1013
(2007/10/02)
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