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Pentafluorosulfanyl-substituted biaryl derivatives as MATE-type transporter inhibitors targeting drug-resistant bacteria. Bioorg Med Chem 2024; 99:117606. [PMID: 38262304 DOI: 10.1016/j.bmc.2024.117606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 01/12/2024] [Accepted: 01/15/2024] [Indexed: 01/25/2024]
Abstract
Multidrug and toxin extrusion (MATE) inhibitors improve the antimicrobial susceptibility of drug-resistant bacteria by preventing the efflux of administered antibiotics. In this study, we optimized the chemical structure of a previously identified bacterial-selective MATE inhibitor 1 (EC50 > 30 µM) to improve its activity further. Compound 1 was divided into three fragments (aromatic part, linker part, and guanidine part), and each part was individually optimized. Compound 31 (EC50 = 1.8 µM), a novel pentafluorosulfanyl-containing molecule synthesized following optimized parts, showed antimicrobial activity against MATE-expressing strains at concentrations lower than conventional inhibitor 1 when co-administrated with norfloxacin. Furthermore, 31 was not cytotoxic at effective concentrations. This suggests that compound 31 can be a promising candidate for combating bacterial infections, particularly those resistant to conventional antibiotics by MATE expression.
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2
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Reactions Using Freons and Halothane as Halofluoroalkyl/Halofluoroalkenyl Building Blocks. CHEM REC 2023; 23:e202300029. [PMID: 37017496 DOI: 10.1002/tcr.202300029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 03/15/2023] [Indexed: 04/06/2023]
Abstract
In recent years, hydrofluorocarbon compounds such as chlorofluorocarbons, hydrochlorofluorocarbons, and 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane) have been used as fluorine-containing building blocks to construct functional fluorine-containing compounds, e. g., polymers, liquid crystals, and medicines. Hydrofluorocarbons promote the formation of reactive fluoroalkyl or fluoroalkenyl species via anionic or radical processes, and these species can act as nucleophiles or electrophiles depending on the reaction conditions. Progress in fluorine chemistry using hydrofluorocarbons in the last 30 years is described in this review and diverse reactions are discussed, including the fluoroalkyl/alkenyl products and proposed mechanisms involved.
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3
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Rhodium-catalyzed intramolecular reductive aldol-type cyclization: Application for the synthesis of a chiral necic acid lactone. Beilstein J Org Chem 2022; 18:1642-1648. [DOI: 10.3762/bjoc.18.176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 11/18/2022] [Indexed: 12/05/2022] Open
Abstract
A rhodium-catalyzed intramolecular reductive aldol-type cyclization is described to give β-hydroxylactones with high diastereoselectivities. The stereoselectivity of this cyclization is highly solvent dependent and can give syn- or anti-β-hydroxylactones with high diastereoselectivity. This methodology was also applied to the synthesis of a chiral necic acid lactone which is a structural component of the pyrrolizidine alkaloid monocrotaline.
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4
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Simple synthesis of multi-halogenated alkenes from 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane). Beilstein J Org Chem 2022; 18:1567-1574. [DOI: 10.3762/bjoc.18.167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 11/07/2022] [Indexed: 11/22/2022] Open
Abstract
A series of aryl fluoroalkenyl ethers that contain chlorine and bromine as well as fluorine atoms were prepared in moderate to good yields via the reactions of phenols and 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane) in the presence of KOH. This simple reaction enabled the construction of highly halogenated compounds with the potential for further functionalization. The reaction involved a highly reactive difluoroethylene intermediate, which was produced by the reaction between halothane and KOH.
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5
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Discovery of benzyloxyphenyl- and phenethylphenyl-imidazole derivatives as a new class of ante–drug type boosters. Bioorg Med Chem Lett 2022; 72:128868. [DOI: 10.1016/j.bmcl.2022.128868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 06/11/2022] [Accepted: 06/22/2022] [Indexed: 11/02/2022]
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6
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Synthesis of 2,2-difluoro-2-arylethylamines as fluorinated analogs of octopamine and noradrenaline. HETEROCYCL COMMUN 2022. [DOI: 10.1515/hc-2022-0005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstrtact
A series of 2,2-difluoro-2-arylethylamines was synthesized as fluorinated analogs of octopamine and noradrenaline with the expectation of bioisosteric OH/F exchanges. The syntheses of these compounds were performed by a Suzuki–Miyaura cross-coupling reaction of 4-(bromodifluoroacetyl)morpholine with aryl boronic acids to produce the intermediate 2,2-difluoro-2-arylacetamides, followed by transformation of difluoroacetamide to difluoroethylamine.
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LCP: Simple Representation of Docking Poses for Machine Learning: A Case Study on Xanthine Oxidase Inhibitors. Mol Inform 2021; 41:e2100245. [PMID: 34843171 DOI: 10.1002/minf.202100245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 11/21/2021] [Indexed: 11/05/2022]
Abstract
In this paper, we propose a simple descriptor called the ligand coordinate profile (LCP) for describing docking poses. The LCP descriptor is generated from the coordinates of the polar hydrogen and heavy atoms of the docked ligand. We hypothesize that the prediction of binding poses can be enhanced through the combination of machine learning methods with the LCP descriptor. Two docking programs were used to predict ligand docking against xanthine oxidase. Four machine learning methods-k-nearest neighbors, random forest, support vector machine, and LightGBM-were used to determine whether machine learning-based models could be used to accurately identify the correct binding poses. Regardless of the machine learning method employed, the LCP descriptor demonstrated improved performance compared to the existing descriptor. The results of the leave-one-pdb-out approach revealed that the influence of the pose descriptor was also significant, as demonstrated through cross-validation. When evaluated using top-N metrics, the machine learning models were generally more effective than the docking programs. In addition, the LCP-based models outperformed those based on the existing descriptor. The results obtained in this study suggest that our proposed binding pose descriptor is effective for improving the docking accuracy of xanthine oxidase inhibitors.
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Importance of the Azole Moiety of Cimetidine Derivatives for the Inhibition of Human Multidrug and Toxin Extrusion Transporter 1 (hMATE1). Chem Pharm Bull (Tokyo) 2021; 69:905-912. [PMID: 34470955 DOI: 10.1248/cpb.c21-00429] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Herein, we describe the design and synthesis of cimetidine analogs, as well as their inhibitory activity toward the human multidrug and toxin extrusion transporter 1 (hMATE1), which is related to nephrotoxicity of drugs. Cimetidine is the histamine H2-receptor antagonist, but also inhibits hMATE1, which is known to cause renal impairment. We designed and synthesized cimetidine analogs to evaluate hMATE1 inhibitory activity to reveal whether the analogs could reduce the inhibition of hMATE1. The results showed that all analogs with an unsubstituted guanidino group exhibited hMATE1 inhibitory activity. On the other hand, there was a clear difference in the hMATE1 inhibitory activity for the other compounds. That is, compounds with a methylimidazole ring exhibited hMATE1 inhibition, while compounds with a phenyl ring did not. The results suggest that the ability to form hydrogen bonds at the azole moiety is strongly involved in the hMATE1 inhibition.
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Identification and Synthesis of DDI-6, a Quinolinol Analog Capable of Activating Both Caenorhabditis elegans and Mouse Spermatozoa. Chem Pharm Bull (Tokyo) 2021; 69:557-563. [PMID: 34078802 DOI: 10.1248/cpb.c21-00127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Sperm activation is an essential process by which the male gametes become capable of fertilization. Because the process in Caenorhabditis elegans is readily reproducible in vitro, this organism serves as an excellent model to investigate it. C. elegans sperm activation in vivo occurs during spermiogenesis. Membranous organelles (MOs) contained within spermatids fuse with the plasma membrane, resulting in extracellular release of their contents and relocation of some proteins indispensable for fertilization from the MO membrane onto the sperm surface. Intriguingly, these cytological alternations are exhibited similarly in mouse spermatozoa during the acrosome reaction, which also represents a form of sperm activation, prompting us to hypothesize that C. elegans and mice share a common mechanism for sperm activation. To explore this, we first screened a chemical library to identify compounds that activate C. elegans spermatozoa. Because a quinolinol analog named DDI-6 seemed to be a candidate sperm activator, we synthesized it to use for further analyses. This involved direct dechlorination and hydrogenolysis of commercially available 5-chloro-8-quinolinol, both of which are key steps to yield 1,2,3,4-tetrahydro-8-quinolinol, and we subsequently introduced the sulfonamide group to the compound. When C. elegans spermatids were stimulated with solvent alone or the newly synthesized DDI-6, approx. 3% and approx. 28% of spermatids became MO-fused spermatozoa, respectively. Moreover, DDI-6 triggered the acrosome reaction in approx. 20% of mouse spermatozoa, while approx. 12% became acrosome-reacted after mock stimulation. Thus, DDI-6 serves as a moderately effective activator for both C. elegans and mouse spermatozoa.
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Effect of Learning Dataset for Identification of Active Molecules: A Case Study of Integrin αIIbβ3 Inhibitors. Mol Inform 2021; 40:e2060040. [PMID: 33738924 DOI: 10.1002/minf.202060040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 01/30/2021] [Indexed: 01/13/2023]
Abstract
Efficient in silico approaches are needed to identify strong integrin αIIbβ3 inhibitors through a small number of measurements. To address the challenge, we investigated the effect of learning dataset on the classification performance of machine learning models focusing on weak and inactive compounds. The structure and activity information of the compounds were obtained from ChEMBL, and pCHEMBL values were used to classify them as active, inactive, or weak. Datasets with various imbalance levels from active:inactive=1 : 1 to 1 : 1000 were used for the machine learning. The prediction scores of the weak samples were found to lie between the predictive values of active and inactive compounds. In addition, another dataset that consists of 149 actives and 6.9 million inactives was screened; the results indicated that the number of positive predictions decreased for models trained with a higher number of inactives. Although there is a trade-off between false positives and false negatives, for determination of compounds with strong activity using a reduced number of measurements, it is better to use a large number of inactives for learning and identifying compounds that score higher than the weak samples.
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11
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Synthesis of aryl 2-bromo-2-chloro-1,1-difluoroethyl ethers through the base-mediated reaction between phenols and halothane. Beilstein J Org Chem 2021; 17:89-96. [PMID: 33519995 PMCID: PMC7814179 DOI: 10.3762/bjoc.17.9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 12/11/2020] [Indexed: 12/26/2022] Open
Abstract
An efficient and convenient method for the synthesis of structurally unique and highly functionalized aryl 2-bromo-2-chloro-1,1-difluoroethyl ethers has been developed. This approach exhibits a broad reaction scope, a simple operation and without the need of any expensive transition-metal catalyst, highly toxic or corrosive reagents. Notably, we demonstrate the potential utility of halothane for the synthesis of aryl gem-difluoroalkyl ethers containing the bromochloromethyl group.
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12
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Abstract
β-Lactams, found in β-lactam antibiotics, are the structurally distorted cyclic
compounds being subjected to nucleophilic acyl substitution reaction. α-Fluorination of β
-lactams is a simple and expedient approach to control the reactivity of β-lactam ring toward
nucleophilic attack, which would hopefully lead to the new design of future antibiotics.
From the viewpoint of obtaining multisubstituted α-fluoro-β-lactams, α-bromo-α-
fluoro-β-lactams are considered as key compounds for structure functionalization, including
nucleophilic substitution reaction, aldol-type reaction and metal-catalyzed crosscoupling
reaction. All the reactions can be conducted smoothly to afford a variety of multisubstituted
α-fluoro-β-lactams. During the course of the examination, chiral α,α-difluoro-
β-lactams and α -bromo-β-fluoro-α-lactams are successfully obtained, which are considered
potent precursors for making stereocontrolled multisubstituted α-fluoro-β-lactams.
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13
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Reductive Carbon–Carbon Bond Forming Reactions with Carbonyls Mediated by Rh–H Complexes. European J Org Chem 2020. [DOI: 10.1002/ejoc.202001041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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14
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Abstract
α,α-Difluoro-β-lactams successfully underwent ring-opening aminolysis with various amino acids in 2,2,2-trifluoroethanol to afford fluorine-containing peptides. In this aminolysis, it was found that 2,2,2-trifluoroethanol first attacked the α,α-difluoro-β-lactams with cleavage of lactam ring to form the corresponding open-chain 2,2,2-trifluoroethyl esters as reactive intermediates. The trifluoroethyl esters were more electrophilic compared with the corresponding methyl ester and thereby accelerated the aminolysis with various amino acids to form β-amino acid peptides with α,α-difluoromethylene unit.
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Synthesis of new fluorescent molecules having an aggregation-induced emission property derived from 4-fluoroisoxazoles. Beilstein J Org Chem 2020; 16:1411-1417. [PMID: 32647543 PMCID: PMC7323617 DOI: 10.3762/bjoc.16.117] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 06/09/2020] [Indexed: 01/02/2023] Open
Abstract
Fluorescent molecules based on a fluorinated isoxazole scaffold were synthesized and investigated for their photochemical properties. The introduction of a fluorine substituent into 3,5-diarylisoxazoles led to an increase of fluorescence intensity and exhibited a redshift in the emission intensity. α-Fluorinated boron ketoiminates (F-BKIs) were also synthesized via a ring-opening reaction of 4-fluoroisoxazoles and exhibited highly fluorescent luminescence and aggregation-induced emission (AIE), showing promise as a new fluorophore.
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Abstract
A mild and convenient reaction for oxidative trifluoromethylation of terminal alkenes was developed using in situ generated AgCF3 in the presence of a copper catalyst. The reaction proceeded under an air atmosphere to afford trifluoromethylated allylic compounds in moderate to good yield. This reaction, with no need for highly hygroscopic or corrosive reagents, features not only a simple operation but also various functional group tolerances.
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17
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Effect of Structural Descriptors on the Design of Cyclin Dependent Kinase Inhibitors Using Similarity‐based Molecular Evolution. Mol Inform 2020; 39:e1900126. [DOI: 10.1002/minf.201900126] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 01/14/2020] [Indexed: 12/22/2022]
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18
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Synthesis of Small Fluorescent Molecules and Evaluation of Photophysical Properties. J Org Chem 2020; 85:1253-1258. [PMID: 31851516 DOI: 10.1021/acs.joc.9b02857] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A series of aniline-based fluorophores were newly synthesized. To increase their fluorescence quantum yields, it was particularly important to substitute 3,3,3-trifluoroprop-1-enyl (TFPE) groups next to the amino group to benefit from an extended π-electron delocalization. Among these, 5-CN-2-TFPE-aniline was found to behave as an excellent fluorophore with a reasonable fluorescence quantum yield of 0.89 even in aqueous solution. l-Alanine peptide, a nonfluorescent analogue of 5-CN-2-TFPE-aniline, was synthesized and successfully employed as an enzyme probe to detect aminopeptidase N activity.
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Construction of Quaternary Carbon Center by the Reaction of Aza-o-Quinone Methide Mediated Carbocation Intermediate. HETEROCYCLES 2020. [DOI: 10.3987/com-19-s(f)33] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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20
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Proteinase K is an activator for the male-dependent spermiogenesis pathway in Caenorhabditis elegans: Its application to pharmacological dissection of spermiogenesis. Genes Cells 2019; 24:244-258. [PMID: 30656805 DOI: 10.1111/gtc.12670] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Revised: 12/22/2018] [Accepted: 01/08/2019] [Indexed: 11/30/2022]
Abstract
Caenorhabditis elegans spermiogenesis involves spermatid activation into spermatozoa. Activation occurs through either SPE-8 class-dependent or class-independent pathways. Pronase (Pron) activates the SPE-8 class-dependent pathway, whereas no in vitro tools are available to stimulate the SPE-8 class-independent pathway. Thus, whether there is a functional relationship between these two pathways is currently unclear. In this study, we found that proteinase K (ProK) can activate the SPE-8 class-independent pathway. In vitro spermiogenesis assays using Pron and ProK suggested that SPE-8 class proteins act in the hermaphrodite- and male-dependent spermiogenesis pathways and that some spermatid proteins presumably working downstream of spermiogenesis pathways, including MAP kinases, are preferentially involved in the SPE-8 class-dependent pathway. We screened a library of chemicals, and a compound that we named DDI-1 inhibited both Pron- and ProK-induced spermiogenesis. To our surprise, several DDI-1 analogues that are structurally similar to DDI-1 blocked Pron, but not ProK, induced spermiogenesis. Although the mechanism by which DDI-1 blocks spermiogenesis is yet unknown, we have begun to address this issue by selecting two DDI-1-resistant mutants. Collectively, our data support a model in which C. elegans male and hermaphrodite spermiogenesis each has its own distinct, parallel pathway.
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Lewis acid promoted fluorine-alkoxy group exchange reactions for the synthesis of 5-alkoxy-4,4-difluoroisoxazoline systems. Org Biomol Chem 2019; 17:2818-2823. [DOI: 10.1039/c9ob00097f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Lewis acid promoted substitution of fluorine yields novel 5-alkoxylated 4,4-difluoroisoxazolines via SN1 type processes.
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Crystal Structure of ( E)-2-(3,3,3-tri-fluoro-prop-1-en-1-yl)aniline. Acta Crystallogr E Crystallogr Commun 2018; 74:1448-1450. [PMID: 30319798 PMCID: PMC6176427 DOI: 10.1107/s2056989018012756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 09/10/2018] [Indexed: 06/08/2023]
Abstract
The mol-ecule of the title compound, C9H8F3N, adopts an E configuration with respect to the C=C double bond. The dihedral angle between the benzene ring and the prop-1-enyl group is 25.4 (3)°. In the crystal, mol-ecules are linked via pairs of N-H⋯F hydrogen bonds into inversion dimers with an R 2 2(16) ring motif. The dimers are linked by C-H⋯N hydrogen bonds, forming a ribbon structure along the b-axis direction. The ribbons are linked by N-H⋯π and C-H⋯π inter-actions, generating a three-dimensional network.
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LB1532 Syntheses and physicochemical investigations of optically active ceramide NDS. J Invest Dermatol 2018. [DOI: 10.1016/j.jid.2018.06.065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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24
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Determination of Ochratoxin A in Beer by Immunoaffinity Cleanup and Liquid Chromatography with Tandem Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY OF BREWING CHEMISTS 2018. [DOI: 10.1094/asbcj-2008-0226-02] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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25
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Analysis of Simultaneous Screening for 277 Pesticides in Malt and Beer by Liquid Chromatography with Tandem Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY OF BREWING CHEMISTS 2018. [DOI: 10.1094/asbcj-64-0139] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Decarboxylative aldol reaction of α,α-difluoro-β-ketocarboxylate salt: a facile method for generation of difluoroenolate. RSC Adv 2018; 8:20568-20575. [PMID: 35542341 PMCID: PMC9080823 DOI: 10.1039/c8ra02440e] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 05/29/2018] [Indexed: 11/21/2022] Open
Abstract
We developed a decarboxylative aldol reaction using α,α-difluoro-β-ketocarboxylate salt, carbonyl compounds, and ZnCl2/N,N,N′,N′-tetramethylethylenediamine. The generation of difluoroenolate proceeded smoothly under mild heating to provide α,α-difluoro-β-hydroxy ketones in good to excellent yield (up to 99%). The α,α-difluoro-β-ketocarboxylate salt was bench stable and easy to handle under air, which realizes a convenient and environmentally friendly methodology for synthesis of difluoromethylene compounds. A ZnCl2/N,N,N′,N′-tetramethylethylenediamine complex promoted decarboxylative aldol reaction of α,α-difluoro-β-ketocarboxylate salt with carbonyl compounds has been developed.![]()
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Development of a fluorogenic small substrate for dipeptidyl peptidase-4. Beilstein J Org Chem 2017; 13:2690-2697. [PMID: 29564006 PMCID: PMC5753067 DOI: 10.3762/bjoc.13.267] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 11/29/2017] [Indexed: 11/23/2022] Open
Abstract
A series of aniline and m-phenylenediamine derivatives with electron-withdrawing 3,3,3-trifluoropropenyl substituents were synthesized as small and chemically stable fluorescent organic compounds. Their fluorescence performances were evaluated by converting 2,4-disubstituted aniline 1 to the non-fluorescent dipeptide analogue H-Gly-Pro-1 for the use as a fluorogenic substrate for dipeptidyl peptidase-4 (DPP-4). The progress of the enzymatic hydrolysis of H-Gly-Pro-1 with DPP-4 was monitored by fluorometric determination of 1 released into the reaction medium. The results suggest that 1 could be used as fluorophore in OFF–ON-type fluorogenic probes.
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Rh-Catalyzed reductive Mannich-type reaction and its application towards the synthesis of (±)-ezetimibe. Beilstein J Org Chem 2016; 12:1608-15. [PMID: 27559413 PMCID: PMC4979637 DOI: 10.3762/bjoc.12.157] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 07/06/2016] [Indexed: 12/02/2022] Open
Abstract
An effective synthesis for syn-β-lactams was achieved using a Rh-catalyzed reductive Mannich-type reaction. A rhodium–hydride complex (Rh–H) derived from diethylzinc (Et2Zn) and a Rh catalyst was used for the 1,4-reduction of an α,β-unsaturated ester to give a Reformatsky-type reagent, which in turn, reacted with an imine to give the syn-β-lactam. Additionally, the reaction was applied to the synthesis of (±)-ezetimibe, a potent β-lactamic cholesterol absorption inhibitor.
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A dramatic enhancing effect of InBr3 towards the oxidative Sonogashira cross-coupling reaction of 2-ethynylanilines. Org Biomol Chem 2016; 14:2127-33. [PMID: 26782816 DOI: 10.1039/c5ob02558c] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The addition of InBr3 to the oxidative Sonogashira cross-coupling reaction of 2-ethynylaniline with (E)-trimethyl(3,3,3-trifluoroprop-1-enyl)silane led to a dramatic increase in the reactivity to afford the corresponding 1,3-enynes bearing a trifluoromethyl group on their terminal sp(2) carbon. The subsequent cyclization of these 1,3-enynes under palladium catalysis provides access to the corresponding indoles bearing a 3,3,3-trifluoroprop-1-enyl group at their 2-position.
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Synthesis of fluorinated isoxazoles using Selectfluor™: preparation and characterization of 4-fluoroisoxazole, 4,4,5-trifluoroisoxazoline and 4,4-difluoro-5-hydroxyisoxazoline systems from one-pot and multi-step processes. Tetrahedron 2016. [DOI: 10.1016/j.tet.2016.02.026] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Diastereoselective Synthesis of syn-β-Lactams Using Rh-Catalyzed Reductive Mannich-Type Reaction of α,β-Unsaturated Esters. J Org Chem 2015. [PMID: 26203668 DOI: 10.1021/acs.joc.5b01233] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The combination of Et2Zn and RhCl(PPh3)3 led to the facile generation of a rhodium-hydride complex (Rh-H) that catalyzed the 1,4-reduction of α,β-unsaturated esters. The resulting rhodium enolate performed as a Reformatsky-type reagent and reacted with various imines to give syn-β-lactams in good to excellent yields with high diastereoselectivity.
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Synthesis of a fluorinated Ezetimibe analogue using radical allylation of α-bromo-α-fluoro-β-lactam. NEW J CHEM 2015. [DOI: 10.1039/c5nj01969a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A facile and efficient synthesis of a fluorinated Ezetimibe analogue was achieved by radical allylation, Wacker oxidation, and nucleophilic arylation of α-bromo-α-fluoro-β-lactam.
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One-pot synthesis of 1,3-enynes with a CF3 group on the terminal sp2 carbon by an oxidative Sonogashira cross-coupling reaction. Org Biomol Chem 2015. [DOI: 10.1039/c5ob01290b] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
One-pot synthesis of 1,3-enynes with a CF3 group on the terminal sp2 carbon was achieved by an oxidative Sonogashira cross-coupling reaction with (E)-trimethyl(3,3,3-trifluoroprop-1-enyl)silane.
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Abstract
A highly reactive alkylrhodium complex was formed from Me(2)Zn and RhCl(PPh(3))(3) and effectively catalyzed a Csp(3)-Csp(3) homocoupling reaction of benzyl halides. A Csp(3)-Csp(3) coupling reaction using Rh catalyst has not been reported up to now. The reaction proceeded under very mild conditions and gave the corresponding homocoupling products even if they had reactive substituents such as an uncovered formyl or hydroxymethyl group.
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Ligand-Promoted Asymmetric Imino-Reformatsky Reaction of Ethyl Dibromofluoroacetate. Org Lett 2014; 16:2080-3. [DOI: 10.1021/ol500631j] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Synthesis of Fluorinated Heterocycles Designed to Deliver the Modified Bioactive Behavior: Synthetic Use of Ethyl Bromodifluoroacetate, Ethyl Dibromofluoroacetate and Fluorine Containing Vinylsilanes. J SYN ORG CHEM JPN 2014. [DOI: 10.5059/yukigoseikyokaishi.72.680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Asymmetric Reductive Aldol-Type Reaction with Carbonyl Compounds Using Dialkyl Tartrate as a Chiral Ligand. Chem Pharm Bull (Tokyo) 2014; 62:956-61. [DOI: 10.1248/cpb.c14-00223] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Enantioselective synthesis of α,α-difluoro-β-lactams using amino alcohol ligands. Org Biomol Chem 2014; 12:6484-9. [DOI: 10.1039/c4ob01184h] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A practical and highly enantioselective Reformatsky reaction of ethyl bromodifluoroacetate with imines using a cheap and commercially available amino alcohol ligand is described.
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Oxidative 3,3,3-trifluoropropylation of arylaldehydes. Beilstein J Org Chem 2013; 9:2417-21. [PMID: 24367408 PMCID: PMC3869248 DOI: 10.3762/bjoc.9.279] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Accepted: 10/10/2013] [Indexed: 11/23/2022] Open
Abstract
A reaction between (E)-trimethyl(3,3,3-trifluoroprop-1-en-1-yl)silane (1) and arylaldehydes 2 was triggered by fluoride anions to afford aryl 3,3,3-trifluoropropyl ketones 3 in moderate to good yield. A mechanistic study of this reaction indicated that it occurred via an allyl alkoxide (4). A subsequent 1,3-proton shift of the benzylic proton of 4 forms 3. This reaction involves oxidative 3,3,3-trifluoropropylation of an arylaldehyde to afford 4,4,4-trifluoro-1-arylbutan-1-one.
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Direct and diastereoselective alkylation and aldol reactions of α-bromo-α-fluoro-β-lactams. J Org Chem 2013; 78:7903-11. [PMID: 23865894 DOI: 10.1021/jo401072h] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Herein, we describe the development of a method for the direct alkylation and aldol reaction of α-bromo-α-fluoro-β-lactams. This method provides facile access to a wide range of 3-alkyl- and 3-hydroxyalkyl-fluoro-β-lactams in good yields under mild conditions. The products were obtained with complete diastereoselectivity with regard to the relative configuration of the β-lactam ring at C3 and C4 positions. The reaction conditions were tolerant of a broad range of electrophiles, which highlights the overall scope and utility of this procedure.
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Synthesis of 2-Aryl-3-trifluoromethylquinolines Using (E)-Trimethyl(3,3,3-trifluoroprop-1-enyl)silane. J Org Chem 2013; 78:6196-201. [DOI: 10.1021/jo400859s] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Simple Synthesis of β-Trifluoromethylstyrenes Using (E)-Trimethyl-(3,3,3-trifluoroprop-1-enyl)silane. Org Lett 2012; 14:2286-9. [DOI: 10.1021/ol300670n] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Reductive Reformatsky-Honda Reaction of α,β-Unsaturated Esters: Facile Formation of 1,3-Dicarbonyl Compounds and β-Hydroxy Esters. Adv Synth Catal 2012. [DOI: 10.1002/adsc.201100463] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Simple, chemoselective, and diastereoselective Reformatsky-type synthesis of α-bromo-α-fluoro-β-lactams. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2010.02.023] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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