- Discovery of SARS-CoV-2 main protease inhibitors using a synthesis-directed: De novo design model
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The SARS-CoV-2 main viral protease (Mpro) is an attractive target for antivirals given its distinctiveness from host proteases, essentiality in the viral life cycle and conservation across coronaviridae. We launched the COVID Moonshot initiative to rapidly develop patent-free antivirals with open science and open data. Here we report the use of machine learning for de novo design, coupled with synthesis route prediction, in our campaign. We discover novel chemical scaffolds active in biochemical and live virus assays, synthesized with model generated routes. This journal is
- Morris, Aaron,McCorkindale, William,Drayman, Nir,Chodera, John D.,Tay, Sava?,London, Nir,Lee, Alpha A.
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supporting information
p. 5909 - 5912
(2021/06/27)
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- Synthetic Access to gem-Difluoropropargyl Vinyl Ethers and Their Application to Propargyl Claisen Rearrangement
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With the increasing importance of fluorine to medicinal chemistry and other areas, methods to access various fluorinated compounds are needed. Herein, we report the synthesis of difluoropropargyl vinyl ethers from ketones and aldehydes using difluoropropargyl bromide dicobalt complexes. We applied difluoropropargyl vinyl ethers to the synthesis of difluorodienone or difluoroallene under thermal conditions and trifluoro-pyran under acid-catalyzed conditions.
- Okamura, Toshitaka,Koyamada, Kenta,Kanazawa, Junichiro,Miyamoto, Kazunori,Iwabuchi, Yoshiharu,Uchiyama, Masanobu,Kanoh, Naoki
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p. 1911 - 1924
(2020/12/23)
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- Kinetic Resolution of Neopentylic Secondary Alcohols by Cu-H-Catalyzed Enantioselective Silylation with Hydrosilanes
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A nonenzymatic kinetic resolution of sterically congested alcohols having a quaternary carbon atom in the β-position is reported. The catalyst system CuCl/NaOtBu/(R,R)-Ph-BPE together with a 3,5-xylyl-substituted tertiary hydrosilane enable enantioselective silylation of the hydroxy group. Several alcohols are obtained with good to excellent selectivity factors, and there are no other known straightforward methods to access these motifs.
- Oestreich, Martin,Papadopulu, Zaneta
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supporting information
p. 438 - 441
(2021/01/13)
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- Synthesis of Arylacetaldehydes by Iridium-Catalyzed Arylation of Vinylene Carbonate with Arylboronic Acids
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The one-step synthesis of arylacetaldehydes by carbon–carbon bond formation between formylmethyl and aryl groups has been realized by the reaction of vinylene carbonate with arylboronic acids in the presence of an iridium/bisphosphine catalyst and a catalytic amount of tetrahydroxydiboron.
- Wang, Zhe,Xue, Fei,Hayashi, Tamio
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supporting information
p. 11054 - 11057
(2019/07/17)
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- Transaminase-Catalyzed Continuous Synthesis of Biogenic Aldehydes
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The physiological role of biogenic aldehydes, such as 3,4-dihydroxyphenylacetaldehyde (DOPAL), has been associated with cardiovascular and neurodegenerative disorders. The availability of these substrates is limited and robust synthetic methodologies would greatly facilitate further biological studies. Herein, a transaminase-mediated single-step process in continuous mode, which leads to excellent product yields (90–95 %), is reported. Coimmobilization of the pyridoxal phosphate (PLP) cofactor eliminated the need for exogenous addition of this reagent without affecting the longevity of the system, delivering a truly self-sufficient process.
- Contente, Martina L.,Paradisi, Francesca
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p. 2830 - 2833
(2019/08/12)
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- Stereoselective Synthesis of Vinylboronates by Rh-Catalyzed Borylation of Stereoisomeric Mixtures
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The stereoselective preparation of vinylboronates via rhodium-catalyzed borylation of E/Z mixtures of vinyl actetates is described, and this method was also extended to synthesis of vinyldiboronates. These transformations feature high functional group compatibility and mild reaction conditions. Control experiments support a mechanism that involved a Rh-catalyzed borylation-isomerization sequence. The isomerization of (Z)-vinylboronates to (E)-isomers was also demonstrated.
- Li, Shenhuan,Li, Jie,Xia, Tianlai,Zhao, Wanxiang
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supporting information
p. 462 - 468
(2019/03/28)
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- New Stereoselective Biocatalysts for Carboligation and Retro-Aldol Cleavage Reactions Derived from d-Fructose 6-Phosphate Aldolase
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d-Fructose 6-phosphate aldolase (FSA) catalyzes the asymmetric cross-aldol addition of phenylacetaldehyde and hydroxyacetone. We conducted structure-guided saturation mutagenesis of noncatalytic active-site residues to produce new FSA variants, with the goal of widening the substrate scope of the wild-type enzyme toward a range of para- A nd meta-substituted arylated aldehydes. After a single generation of mutagenesis and selection, enzymes with diverse substrate selectivity scopes were identified. The kinetic parameters and stereoselectivities for a subset of enzyme/substrate combinations were determined for the reactions in both the aldol addition and cleavage reaction directions. The achieved collection of new aldolase enzymes provides new tools for controlled asymmetric synthesis of substituted aldols.
- Ma, Huan,Engel, Sarah,Enugala, Thilak Reddy,Al-Smadi, Derar,Gautier, Candice,Widersten, Mikael
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p. 5877 - 5885
(2018/10/05)
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- Molecular structures of cdc2-like kinases in complex with a new inhibitor chemotype
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Cdc2-like kinases (CLKs) represent a family of serine-threonine kinases involved in the regulation of splicing by phosphorylation of SR-proteins and other splicing factors. Although compounds acting against CLKs have been described, only a few show select
- Walter, Anne,Chaikuad, Apirat,Helmer, Renate,Loa?c, Nadège,Preu, Lutz,Ott, Ingo,Knapp, Stefan,Meijer, Laurent,Kunick, Conrad
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- Synthesis of Substrates for Aldolase-Catalysed Reactions: A Comparison of Methods for the Synthesis of Substituted Phenylacetaldehydes
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Methods for the synthesis of phenylacetaldehydes (oxidation, one-carbon chain extension) were compared by using the synthesis of 4-methoxyphenylacetaldehyde as a model example. Oxidations of 4-methoxyphenylethanol with activated DMSO (Swern oxidation) or manganese dioxide gave unsatisfactory results; whereas oxidation with 2-iodoxybenzoic acid (IBX) produced 4-methoxyphenylacetaldehyde in reasonable (75%) yield. However, Wittig-type one-carbon chain extension with methoxymethylene-triphenylphosphine followed by hydrolysis gave an excellent (81% overall) yield of 4-methoxyphenylacetaldehyde from 4-methoxybenzaldehyde (a cheap starting material). This approach was subsequently used to synthesise a set of 10 substituted phenylacetaldehydes in good to excellent yields.
- Al-Smadi, Derar,Enugala, Thilak Reddy,Norberg, Thomas,Kihlberg, Jan,Widersten, Mikael
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supporting information
p. 1187 - 1190
(2018/03/26)
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- Novel Hypoxia-Inducible Factor 1α (HIF-1α) Inhibitors for Angiogenesis-Related Ocular Diseases: Discovery of a Novel Scaffold via Ring-Truncation Strategy
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Ocular diseases featuring pathologic neovascularization are the leading cause of blindness, and anti-VEGF agents have been conventionally used to treat these diseases. Recently, regulating factors upstream of VEGF, such as HIF-1α, have emerged as a desirable therapeutic approach because the use of anti-VEGF agents is currently being reconsidered due to the VEGF action as a trophic factor. Here, we report a novel scaffold discovered through the complete structure-activity relationship of ring-truncated deguelin analogs in HIF-1α inhibition. Interestingly, analog 6i possessing a 2-fluorobenzene moiety instead of a dimethoxybenzene moiety exhibited excellent HIF-1α inhibitory activity, with an IC50 value of 100 nM. In particular, the further ring-truncated analog 34f, which showed enhanced HIF-1α inhibitory activity compared to analog 2 previously reported by us, inhibited in vitro angiogenesis and effectively suppressed hypoxia-mediated retinal neovascularization. Importantly, the heteroatom-substituted benzene ring as a key structural feature of analog 34f was identified as a novel scaffold for HIF-1α inhibitors that can be used in lieu of a chromene ring.
- An, Hongchan,Lee, Seungbeom,Lee, Jung Min,Jo, Dong Hyun,Kim, Joohwan,Jeong, Yoo-Seong,Heo, Mi Jeong,Cho, Chang Sik,Choi, Hoon,Seo, Ji Hae,Hwang, Seyeon,Lim, Jihye,Kim, Taewoo,Jun, Hyoung Oh,Sim, Jaehoon,Lim, Changjin,Hur, Joonseong,Ahn, Jungmin,Kim, Hyun Su,Seo, Seung-Yong,Na, Younghwa,Kim, Seok-Ho,Lee, Jeewoo,Lee, Jeeyeon,Chung, Suk-Jae,Kim, Young-Myeong,Kim, Kyu-Won,Kim, Sang Geon,Kim, Jeong Hun,Suh, Young-Ger
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p. 9266 - 9286
(2018/10/24)
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- Hypervalent Iodine(III)-Mediated Cascade Cyclization of Propargylguanidines and Total Syntheses of Kealiinine B and C
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An oxidative cascade cyclization of propargylguanidines promoted by phenyliodonium diacetate (PIDA) was developed. The protocol provides an efficient route for the synthesis of the alkaloids kealiinines B and C as well as homologues. The difference in the electronic nature of the acetylene substituent resulted in two ways of the cyclization. A plausible mechanism is proposed based on the experimental results.
- Tian, Guilong,Fedoseev, Pavel,Van der Eycken, Erik V.
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p. 5224 - 5227
(2017/04/24)
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- Biocatalytic Formal Anti-Markovnikov Hydroamination and Hydration of Aryl Alkenes
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Biocatalytic anti-Markovnikov alkene hydroamination and hydration were achieved based on two concepts involving enzyme cascades: epoxidation-isomerization-amination for hydroamination and epoxidation-isomerization-reduction for hydration. An Escherichia coli strain coexpressing styrene monooxygenase (SMO), styrene oxide isomerase (SOI), ω-transaminase (CvTA), and alanine dehydrogenase (AlaDH) catalyzed the hydroamination of 12 aryl alkenes to give the corresponding valuable terminal amines in high conversion (many ≥86%) and exclusive anti-Markovnikov selectivity (>99:1). Another E. coli strain coexpressing SMO, SOI, and phenylacetaldehyde reductase (PAR) catalyzed the hydration of 12 aryl alkenes to the corresponding useful terminal alcohols in high conversion (many ≥80%) and very high anti-Markovnikov selectivity (>99:1). Importantly, SOI was discovered for stereoselective isomerization of a chiral epoxide to a chiral aldehyde, providing some insights on enzymatic epoxide rearrangement. Harnessing this stereoselective rearrangement, highly enantioselective anti-Markovnikov hydroamination and hydration were demonstrated to convert α-methylstyrene to the corresponding (S)-amine and (S)-alcohol in 84-81% conversion with 97-92% ee, respectively. The biocatalytic anti-Markovnikov hydroamination and hydration of alkenes, utilizing cheap and nontoxic chemicals (O2, NH3, and glucose) and cells, provide an environmentally friendly, highly selective, and high-yielding synthesis of terminal amines and alcohols.
- Wu, Shuke,Liu, Ji,Li, Zhi
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p. 5225 - 5233
(2017/08/17)
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- Efficient epoxide isomerization within a self-assembled hexameric organic capsule
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The isomerization of epoxides to the corresponding carbonyl compounds is efficiently catalyzed by the supramolecular organic nano-capsule formed by the self-assembly of six resorcin[4]arene units. The capsule provides a combination of weak Br?nsted acidity and a suitable nano-environment that favors the metal-free isomerization reaction.
- Caneva, Thomas,Sperni, Laura,Strukul, Giorgio,Scarso, Alessandro
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p. 83505 - 83509
(2016/11/01)
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- Searching for Dual Inhibitors of the MDM2-p53 and MDMX-p53 Protein-Protein Interaction by a Scaffold-Hopping Approach
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Two libraries of substituted benzimidazoles were designed using a 'scaffold-hopping' approach based on reported MDM2-p53 inhibitors. Substituents were chosen following library enumeration and docking into an MDM2 X-ray structure. Benzimidazole libraries were prepared using an efficient solution-phase approach and screened for inhibition of the MDM2-p53 and MDMX-p53 protein-protein interactions. Key examples showed inhibitory activity against both targets.
- Zaytsev, Andrey,Dodd, Barry,Magnani, Matteo,Ghiron, Chiara,Golding, Bernard T.,Griffin, Roger J.,Liu, Junfeng,Lu, Xiaohong,Micco, Iolanda,Newell, David R.,Padova, Alessandro,Robertson, Graeme,Lunec, John,Hardcastle, Ian R.
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p. 180 - 189
(2015/02/19)
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- Synthesis of 3-Arylpyridines via Palladium/Copper-Catalyzed Annulation of Allylamine/1,3-Propanediamine and Aldehydes
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A novel and efficient method for the synthesis of 3-arylpyridines from allylamine/propanediamine and aldehydes by palladium/copper-catalyzed oxidative tandem cyclization has been developed. With this reaction, a series of desired 3-arylpyridines was synthesized in moderate yields via C-C/C-N bond formation and 6-endo/exo-trig cyclization.
- Yang, Xiaodong,Yang, Shenghua,Xiang, Likui,Pang, Xiaobo,Chen, Baohua,Huang, Guosheng,Yan, Rulong
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p. 3732 - 3736
(2016/01/25)
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- Borontribromide-mediated C-C bond formation in cyclic ketones: A transition metal free approach
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Borontribromide (BBr3) is a well-known demethylating agent. The current investigation was focused on a new application of borontribromide as a C-C bond forming agent in cyclic ketones. In this study, borontribromide mediated C-C bond formation reactions of tetralones, chromenone, thiochromenone and indanones were explored. A methoxy group containing ketones showed selective C-C bond formation reaction instead of demethylation of the methoxy group. MM2 steric energy calculations for the final products showed that the reaction favored the formation of exo- or endo-cyclic double bond containing products, depending upon their low MM2 steric energy in a specific frame structure, as observed in X-ray crystallography. A comprehensive crystallographic and pi-stacking analysis of product 10a demonstrated the formation of 10a as an enantiomeric mixture, and its centre of inversion was stabilized by a set of three unique pi-pi interactions.
- Ahmad, Imran,Pathak, Vinay,Vasudev, Prema G.,Maurya, Hardesh K.,Gupta, Atul
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p. 24619 - 24634
(2014/07/07)
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- Total synthesis of (±)-cavicularin: Control of pyrone diels-alder regiochemistry using isomeric vinyl sulfones
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An intramolecular pyrone Diels-Alder reaction-elimination retro-Diels-Alder cascade of a vinyl sulfone was used in the synthesis of cavicularin, a molecule possessing conformational chirality. The vinyl sulfone substitution pattern allowed for regiocontrol in the Diels-Alder cascade event.
- Zhao, Peng,Beaudry, Christopher M.
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supporting information
p. 402 - 405
(2013/03/13)
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- The catalytic potential of Coptis japonica NCS2 revealed - Development and utilisation of a fluorescamine-based assay ETI
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The versatility and potential of a norcoclaurine synthase (NCS) from Coptis japonica NCS2 has been investigated, together with the development and application of a novel fluorescence-based high-throughput assay using nearly forty amines/aldehydes. The stereocontrol exerted by CjNCS2 on selected non-natural substrates has been determined, where the tetrahydroisoquinolines (THIAs) were formed as the (1S)-isomer in >95% ee, as observed with the natural product norcoclaurine. Docking calculations involving THIA mechanism intermediates, utilising the reported Thalictrum flavum NCS X-ray crystallographic structure, were carried out and combined with the CjNCS2 screening results to further understand the mode of action of NCS. These findings suggested that in addition to the key active-site residues K122 and E110, D141 is also mechanistically essential for the enzymatic transformation. The exceptional tolerance of NCS towards aldehyde substrates is furthermore supported by our proposed mechanism in which the aldehydes protrude out of the enzymatic pocket. Copyright
- Pesnot, Thomas,Gershater, Markus C.,Ward, John M.,Hailes, Helen C.
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supporting information
p. 2997 - 3008
(2013/01/15)
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- First total synthesis of tenuifolin via PIFA mediated oxidative biaryl coupling
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The first total synthesis of a sesquiterpenoid, tenuifolin, was achieved in seven linear steps. Phenyliodine(III) bis(trifluoacetate) (PIFA) mediated oxidative biaryl coupling was employed as a key step to construct the central seven-membered ring with a double bond. The double bond formation was also exploited.
- Tang, Changhua,Li, Ziyuan,Wang, Yiyun,Xu, Jinyi,Kong, Lingyi,Yao, Hequan,Wu, Xiaoming
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p. 3275 - 3278
(2011/07/08)
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- Synthesis of bruguierol A employing ring closing metathesis
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An expedient synthesis of bruguierol A encompassing a novel 2,3-benzo-8-oxabicyclo[3.2.1]octane ring system is described employing ring closing metathesis to generate the oxa-bridged tricyclic core.
- Sarkar, Debayan,Venkateswaran, Ramanathapuram V.
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scheme or table
p. 3232 - 3233
(2011/06/28)
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- Structure-based design of isoindoline-1,3-diones and 2,3- dihydrophthalazine-1,4-diones as novel B-Raf inhibitors
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Structure-guided design led to the discovery of novel chemical scaffolds for B-Raf inhibitors. Both type I and type II kinase inhibitors have been explored and lead compounds with good potency and excellent selectivity have been identified.
- Wang, Xiaolun,Salaski, Edward J.,Berger, Dan M.,Powell, Dennis,Hu, Yongbo,Wojciechowicz, Donald,Collins, Karen,Frommer, Eileen
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scheme or table
p. 6941 - 6944
(2012/01/06)
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- Chiral a-substituted allylboronates in a one-pot three-component asymmetric allylic alkylation/carbonyl allylation reaction sequence -Applications to the syntheses of (+)-(3R,5R)-3-hydroxy-5-decanolide and (-)-massoialactone
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The use of different organomagnesium reagents in the copper-catalyzed allylic alkylation of 3-chloropropenyl with chiral phosphoramidite ligands produces the desired a-substituted allylic boronate reagents in high and with modest to high enantioselectivities (up to 96% ee). The size of the incoming alkyl substituent the organomagnesium reagent was found to impact the yield and selectivity of the allylic alkylation. A one-pot for the preparation of these chiral allylic boronates followed by a Lewis acid (BF3) catalyzed addition to aldehydes the desired allylboration products, homoallylic secondary alcohols, in good yields and very high diastereoselectivity.three-component reaction methodology was applied to the syntheses of two lactone-containing natural , (-)-massoialactone and (+)-(3R,5R)-3-hydroxy-5-decanolide. The key step of these syntheses involved the pot enantioselective copper-catalyzed allylic alkylation/allylboration reaction with a benzylic aldehyde, and the desired product in 87% yield, 92% e,and high E/Z selectivity in a ratio of 22:1. Remarkably, the alkylation step of this sequential reaction was performed with a low catalyst loading of 2 mol% on a scale >15 mmol that can provide multiple grams of the three-component product.
- Carosi, Lisa,Hall, Dennis G.
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experimental part
p. 650 - 661
(2009/10/30)
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- N-Propynyl analogs of β-phenylethylidenehydrazines: Synthesis and evaluation of effects on glycine, GABA, and monoamine oxidase
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A group of β-phenylethylidenehydrazines possessing a variety of substituents (Me, OMe, Cl, F, and CF3) at the ortho-, meta-, or para-positions of the phenyl ring, in conjunction with either a N-bis-(2-propynyl) or a N-mono-(2-propynyl) moiety, were synthesized and compared to the novel neuroprotective drug β-phenylethylidenehydrazine (PEH) with regard to their ability to inhibit the enzymes GABA-transaminase (GABA-T) and monoamine oxidase (MAO)-A and -B in vitro in brain tissue. Two of the analogs synthesized (mono- and bis-N-propynylPEH) were also studied ex vivo in rats to compare their effects to those of PEH with regard to ability to inhibit GABA-T and MAO and to change brain levels of several important amino acids. Unlike PEH, none of the new drugs inhibited GABA-T in vitro at 10 or 100 μM, and all of the drugs (including PEH) were poor inhibitors (at 10 μM) of MAO-A and -B in vitro. The two analogs studied ex vivo inhibited GABA-T to a lesser extent than PEH, unlike PEH that did not elevate brain levels of GABA, and inhibited MAO-A and -B more potently than PEH. Interestingly, unlike PEH, the two analogs caused marked increases in brain levels of glycine; because of the current interest in drugs that increase glycine availability in the brain as potential antipsychotic drugs, these two analogs now warrant further investigation.
- MacKenzie, Erin M.,Fassihi, Afshin,Davood, Asghar,Chen, Qiao-Hong,Rauw, Gillian,Rauw, Gail,Knaus, Edward E.,Baker, Glen B.
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experimental part
p. 8254 - 8263
(2009/04/07)
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- Inhibitors of semicarbazide-sensitive amine oxidase (SSAO) and VAP-1 mediated adhesion useful for treatment and prevention of diseases
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Compositions and methods of using compositions for treatment of inflammatory diseases and immune disorders are provided. Allylamino compounds are disclosed which are inhibitors of semicarbazide-sensitive amine oxidase (SSAO) and/or vascular adhesion protein 1 (VAP-1). The compounds have therapeutic utility in suppressing inflammation and inflammatory responses, and in treatment of several disorders, including multiple sclerosis and stroke.
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Page/Page column 68
(2008/06/13)
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- Hepatitis C virus inhibitors
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The present disclosure is generally directed to antiviral compounds, and more specifically directed to compounds which inhibit the function of the NS3 protease (also referred to herein as “serine protease”) encoded by Hepatitis C virus (HCV), compositions comprising such compounds, and methods for inhibiting the function of the NS3 protease.
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Page/Page column 66-67
(2008/06/13)
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- Design and biological evaluation of phenyl-substituted analogs of β-phenylethylidenehydrazine
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β-Phenylethylidenehydrazine (PEH) has been demonstrated previously to be an inhibitor of γ-aminobutyric acid transaminase (GABA-T) and to cause a marked increase in rat brain levels of GABA, a major neurotransmitter. A group of PEH analogs, possessing a variety of substituents (Me, OMe, Cl, F, and CF3) at the 2-, 3-, and 4-positions of the phenyl ring, were synthesized for evaluation as inhibitors of GABA-T. The details of the synthesis and chemical characterization of the analogs are described. Preliminary in vitro screening for GABA-T inhibition showed that all the analogs possessed activity against this enzyme, although substitution of CF3 at the 2- and 4-positions caused reduced activity. One of the drugs, 4-fluoro-β- phenylethylidenehydrazine, was investigated further ex vivo, where it was shown to inhibit GABA-T, elevate brain levels of GABA, and decrease levels of glutamine, similar to the profile observed previously for PEH.
- Sowa, Bernard,Rauw, Gillian,Davood, Asghar,Fassihi, Afshin,Knaus, Edward E.,Baker, Glen B.
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p. 4389 - 4395
(2007/10/03)
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- THIAZOLE AND PYRAZOLE DERIVATIVES AS FLT-3 KINASE INHIBITORS
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The invention relates to thiazole and pyrazole derivatives of formula (I) wherein Q is S and X is C, or Q is CH and X is N; R1 is unsubtituted or substituted phenyl; and R2 is unsubstituted or substituted aryl or heteroaryl; oa a salt of the said compounds, and to processes for the preparation thereof, to pharmaceutical compositions comprising such derivatives and to the use of such derivatives for the preparation of pharmaceutical compositions for the treatment especially of a proliferative disease, such as a tumour disease, in particular such diseases which respond to an inhibition of the FIt-3 kinase.
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Page/Page column 30-31
(2010/02/11)
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- A Convenient Strategy for Homologation of p-Oxygenated Benzaldehydes
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It is shown that p-oxygenated benzaldehydes can be conveniently obtained by pyrolysis of the corresponding oxiranes.
- Haridas, K.,Dev, Sukh
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p. 1018 - 1020
(2007/10/02)
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- A New Synthesis of some naturally occuring Isocoumarins. 8-Hydroxy-3-methyl-3,4-dihydroisocoumarin (Mellein) and 8-Hydroxy-3-methylisocoumarin
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3-Methyl-8-methoxyisochroman (5a) on oxidation furnishes 3-methyl-8-methoxy-3,4-dihydroisocoumarin (6a), and demethylated with hydriodic acid to 3-methyl-8-hydroxy-3,4-dihydroisocoumarin (mellein) (7a).Treatment of 6a with N-bromosuccinimide followed by refluxing with triethylamine furnishes 3-methyl-8-methoxyisocoumarin (8a) which on demethylation with hydriodic acid yields 3-methyl-8-hydroxyisocoumarin (9a). 5a and 3-methyl-6-methoxyisochroman (5b) obtained by treating 3-(m-methoxyphenyl)propan-2-ol (4) with HCHO/HCl are separated by fractional distillation. 4 is obtained from m-methoxyphenylacetaldehyde (3) by Grignard reaction with methylmagnesium bromide.The aldehyde (3) is obtained from m-methoxybenzaldehyde (1) by Darzens glycidic ester condensation followed by hydrolysis and decarboxylation of the resulting product.
- Sinha, Jawahar,Singh, Ramyan Prasad,Srivastava, Jagdish N.
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p. 907 - 909
(2007/10/02)
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