The Experts below are selected from a list of 198 Experts worldwide ranked by ideXlab platform
Bernhard Wunsch - One of the best experts on this subject based on the ideXlab platform.
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Negative allosteric modulators of the GluN2B NMDA receptor with phenylethylamine structure embedded in ring-expanded and ring-contracted scaffolds
European journal of medicinal chemistry, 2020Co-Authors: Louisa Temme, Dirk Schepmann, Dina Robaa, Elena Bechthold, Julian A. Schreiber, Sandeep Gawaskar, Wolfgang Sippl, Guiscard Seebohm, Bernhard WunschAbstract:Abstract A set of GluN2B NMDA receptor antagonists with conformationally restricted phenylethylamine substructure was prepared and pharmacologically evaluated. The phenylethylamine substructure was embedded in ring expanded 3-Benzazocines 4 as well as ring-contracted tetralinamines 6 and indanamines 7. The ligands 4, 6 and 7 were synthesized by reductive alkylation of secondary amine 11, reductive amination of ketones 12 and 16 and nucleophilic substitution of nosylates 14 and 17. The moderate GluN2B affinity of 3-Benzazocine 4d (Ki = 32 nM) translated into moderate cytoprotective activity (IC50 = 890 nM) and moderate ion channel inhibition (60% at 10 μM) in two-electrode voltage clamp experiments with GluN1a/GluN2B expressing oocytes. Although some of the tetralinamines 6 and indanamines 7 showed very high GluN2B affinity (e.g. Ki (7f) = 3.2 nM), they could not inhibit glutamate/glycine inducted cytotoxicity. The low cytoprotective activity of 3-Benzazocines 4, tetralinamines 6 and indanamines 7 was attributed to the missing OH moiety at the benzene ring and/or in benzylic position. Docking studies showed that the novel GluN2B ligands adopt similar binding poses as Ro 25–6981 with the central H-bond interaction between the protonated amino moiety of the ligands and the carbamoyl moiety of Gln110. However, due to the lack of a second H-bond forming group, the ligands can adopt two binding poses within the ifenprodil binding pocket.
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heck reaction of ortho substituted iodobenzenes with α β unsaturated nitriles as a key step in the synthesis of tetrahydro 2 benzazepines and hexahydro 3 Benzazocines
Tetrahedron, 2013Co-Authors: Peer Hasebein, Dirk Schepmann, Katharina Aulinger, Bernhard WunschAbstract:Abstract A novel strategy is reported for the synthesis of tetrahydro-2-benzazepines 2 and hexahydro-3-Benzazocines 3 comprising a Heck reaction of ortho -substituted iodobenzenes 6 and 14 with α,β-unsaturated nitriles. Hydrogenation of the resulting α,β-unsaturated nitriles 7 , 11 , 15 , and 16 was followed by reductive cyclization. It was shown that the formation of 2-benzazepines was faster than the formation of 3-Benzazocines, which was explained by the higher stability of the aliphatic dimethyl acetals in 17 and 18 . The tetrahydro-2-benzazepine 2d with an N -butyl residue reveals very high σ 1 affinity with a K i -value of 2.0 nM.
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2,6-Epoxy-3-Benzazocines: centrally acting N/O-acetals produced by cyclization of amino- and amidoacetals
Archiv der Pharmazie, 1993Co-Authors: Bernhard Wunsch, Georg Höfner, Gerd BauschkeAbstract:Unter sauren Bedingungen cyclisierten die sekundaren Amine 10a und 10b, das primare Amin 15, das Amid 17a und das Urethan 17b zu den 2,6-Epoxy-3-Benzazocinen 11a, 11b, 16, 18a und 18b. Der Ringschlus des inversen Amids 5a zum tricyclischen N/O-acetal 6 gelang jedoch nicht. Mit LiAlH4 lies sich die Epoxybrucke des Urethans 18b zum bicyclischen 3-Benzazocin 20 offnen. - Wahrend das N-(2-Methoxyethyl)-Derivat 11b das Verhalten der Mause nicht beeinfluste, zeigte das N-Methyl-Derivat 11a starke ZNS-Wirkung. 2,6-Epoxy-3-Benzazocines: Centrally Active N/O-Acetals by Cyclization of Amino- and Amidoacetals Under acidic conditions the secondary amines 10a and 10b, the primary amine 15, the amide 17a, and the urethane 17b were cyclized to yield the 2,6-epoxy-3-Benzazocines 11a, 11b, 16, 18a and 18b, respectively. Ring closure of the inverse amide 5a, however, failed to give the tricyclic N/O-acetal 6. With LiAlH4 the epoxy bridge of the urethane 18b was opened to afford the bicyclic 3-Benzazocine 20. - While the N-(2-methoxyethyl) derivative 11b did not influence the behaviour of mice, the N-methyl derivative 11a showed strong central effects.
Dirk Schepmann - One of the best experts on this subject based on the ideXlab platform.
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Negative allosteric modulators of the GluN2B NMDA receptor with phenylethylamine structure embedded in ring-expanded and ring-contracted scaffolds
European journal of medicinal chemistry, 2020Co-Authors: Louisa Temme, Dirk Schepmann, Dina Robaa, Elena Bechthold, Julian A. Schreiber, Sandeep Gawaskar, Wolfgang Sippl, Guiscard Seebohm, Bernhard WunschAbstract:Abstract A set of GluN2B NMDA receptor antagonists with conformationally restricted phenylethylamine substructure was prepared and pharmacologically evaluated. The phenylethylamine substructure was embedded in ring expanded 3-Benzazocines 4 as well as ring-contracted tetralinamines 6 and indanamines 7. The ligands 4, 6 and 7 were synthesized by reductive alkylation of secondary amine 11, reductive amination of ketones 12 and 16 and nucleophilic substitution of nosylates 14 and 17. The moderate GluN2B affinity of 3-Benzazocine 4d (Ki = 32 nM) translated into moderate cytoprotective activity (IC50 = 890 nM) and moderate ion channel inhibition (60% at 10 μM) in two-electrode voltage clamp experiments with GluN1a/GluN2B expressing oocytes. Although some of the tetralinamines 6 and indanamines 7 showed very high GluN2B affinity (e.g. Ki (7f) = 3.2 nM), they could not inhibit glutamate/glycine inducted cytotoxicity. The low cytoprotective activity of 3-Benzazocines 4, tetralinamines 6 and indanamines 7 was attributed to the missing OH moiety at the benzene ring and/or in benzylic position. Docking studies showed that the novel GluN2B ligands adopt similar binding poses as Ro 25–6981 with the central H-bond interaction between the protonated amino moiety of the ligands and the carbamoyl moiety of Gln110. However, due to the lack of a second H-bond forming group, the ligands can adopt two binding poses within the ifenprodil binding pocket.
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Heck Reaction of ortho‐Substituted Iodobenzenes with α,β‐Unsaturated Nitriles as a Key Step in the Synthesis of Tetrahydro‐2‐benzazepines and Hexahydro‐3‐Benzazocines.
ChemInform, 2013Co-Authors: Peer Hasebein, Dirk Schepmann, Katharina Aulinger, Bernhard WuenschAbstract:A novel strategy for the synthesis of benzazepine and Benzazocine derivatives using the title key step is developed.
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heck reaction of ortho substituted iodobenzenes with α β unsaturated nitriles as a key step in the synthesis of tetrahydro 2 benzazepines and hexahydro 3 Benzazocines
Tetrahedron, 2013Co-Authors: Peer Hasebein, Dirk Schepmann, Katharina Aulinger, Bernhard WunschAbstract:Abstract A novel strategy is reported for the synthesis of tetrahydro-2-benzazepines 2 and hexahydro-3-Benzazocines 3 comprising a Heck reaction of ortho -substituted iodobenzenes 6 and 14 with α,β-unsaturated nitriles. Hydrogenation of the resulting α,β-unsaturated nitriles 7 , 11 , 15 , and 16 was followed by reductive cyclization. It was shown that the formation of 2-benzazepines was faster than the formation of 3-Benzazocines, which was explained by the higher stability of the aliphatic dimethyl acetals in 17 and 18 . The tetrahydro-2-benzazepine 2d with an N -butyl residue reveals very high σ 1 affinity with a K i -value of 2.0 nM.
Peter J. Steel - One of the best experts on this subject based on the ideXlab platform.
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Syntheses of Examples of the 5,6-Dihydro-4H-[1,2,3]triazolo[4,5,1-ij]quinoline, 4,5,6,7-Tetrahydro[1,2,3]triazolo[4,5,1-jk][1,4]benzodiazepine, and 5,6,7,8-Tetrahydro-4H-[1,2,3]triazolo[4,5,1-kl][1]Benzazocine Ring Systems
The Journal of organic chemistry, 2003Co-Authors: Alan R. Katritzky, Sergey Bobrov, Kostyantyn Kirichenko, Peter J. SteelAbstract:Lithiation of 1-vinylbenzotriazole 9 with n-BuLi (2 equiv) generates dianion 10, which upon subsequent reaction with 1,2- and 1,4-diketones affords 14 and 13, representatives of the 5,6-dihydro-4H-[1,2,3]triazolo[4,5,1-ij]quinoline 1 and 5,6,7,8-tetrahydro-4H-[1,2,3]triazolo[4,5,1-kl][1]Benzazocine 2 ring systems, respectively. Reactions of dianion 10 with isocyanates give 15a,b, which contain the 4,5,6,7-tetrahydro[1,2,3]triazolo[4,5,1-jk][1,4]benzodiazepine 3 ring system.
Peer Hasebein - One of the best experts on this subject based on the ideXlab platform.
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Heck Reaction of ortho‐Substituted Iodobenzenes with α,β‐Unsaturated Nitriles as a Key Step in the Synthesis of Tetrahydro‐2‐benzazepines and Hexahydro‐3‐Benzazocines.
ChemInform, 2013Co-Authors: Peer Hasebein, Dirk Schepmann, Katharina Aulinger, Bernhard WuenschAbstract:A novel strategy for the synthesis of benzazepine and Benzazocine derivatives using the title key step is developed.
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heck reaction of ortho substituted iodobenzenes with α β unsaturated nitriles as a key step in the synthesis of tetrahydro 2 benzazepines and hexahydro 3 Benzazocines
Tetrahedron, 2013Co-Authors: Peer Hasebein, Dirk Schepmann, Katharina Aulinger, Bernhard WunschAbstract:Abstract A novel strategy is reported for the synthesis of tetrahydro-2-benzazepines 2 and hexahydro-3-Benzazocines 3 comprising a Heck reaction of ortho -substituted iodobenzenes 6 and 14 with α,β-unsaturated nitriles. Hydrogenation of the resulting α,β-unsaturated nitriles 7 , 11 , 15 , and 16 was followed by reductive cyclization. It was shown that the formation of 2-benzazepines was faster than the formation of 3-Benzazocines, which was explained by the higher stability of the aliphatic dimethyl acetals in 17 and 18 . The tetrahydro-2-benzazepine 2d with an N -butyl residue reveals very high σ 1 affinity with a K i -value of 2.0 nM.
Tohru Fukuyama - One of the best experts on this subject based on the ideXlab platform.
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Enantioselective total synthesis of FR900482
The Journal of organic chemistry, 2004Co-Authors: Masashi Suzuki, Mika Kambe, Hidetoshi Tokuyama, Tohru FukuyamaAbstract:The development of two approaches for the enantioselective total synthesis of FR900482 is described. A precursor for the formation of the Benzazocine ring was assembled effectively by a modification of the Sonogashira coupling of an aryl triflate with a chiral acetylene unit derived from tartaric acid and the subsequent novel ketone formation via conjugate addition of pyrrolidine to the o-nitrophenylacetylene derivative. The first-generation approach to the key pentacyclic intermediate of our racemic total synthesis utilizes an intramolecular Mitsunobu reaction of an ω-hydroxynitrobenzenesulfonamide to form the Benzazocine ring and a stepwise sequence to construct the hydroxymethyl group at the C(7) position. The key intermediate could be synthesized in optically pure form via formation of the characteristic hydroxylamine hemiacetal and a stereoselective epoxide formation. In the second-generation approach, the N-hydroxyBenzazocine ring could be constructed directly from an ω-formylnitrobenzene derivative...
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Intramolecular 1,3-Dipolar Cycloaddition Strategy for Enantioselective Synthesis of FR-900482 Analogues
Organic letters, 2001Co-Authors: Mika Kambe, Eri Arai, Masashi Suzuki, And Hidetoshi Tokuyama, Tohru FukuyamaAbstract:Enantioselective synthesis of FR-900482 analogues is described. The key reaction of the synthesis is intramolecular 1,3-dipolar cycloaddition of a highly functionalized nitrile oxide with complete stereo- and regioselectivities to construct the eight-membered Benzazocine ring.