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Ferenc Fulop - One of the best experts on this subject based on the ideXlab platform.
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synthesis and biological evaluation of the new ring system benzo f pyrimido 1 2 d 1 2 3 triazolo 1 5 a 1 4 diazepine and its cycloalkane and Cycloalkene condensed analogues
RSC Advances, 2021Co-Authors: Mohamed El Haimer, Ferenc Fulop, Marta Palko, Matti Haukka, Mario Gajdacs, Istvan ZupkoAbstract:Derivatives of the new ring system benzo[f]pyrimido[1,2-d][1,2,3]triazolo[1,5-a][1,4]diazepinone and its cycloalkane and Cycloalkene condensed analogues have been conveniently synthesized through a three-step reaction sequence. An atom-economical, one-pot, three-step cascade process engaging five reactive centers (amide, amine, carbonyl, azide, and alkyne) has been performed for the synthesis of alicyclic derivatives of quinazolinotriazolobenzodiazepine using cyclohexane, cyclohexene, and norbornene β-amino amides. The stereochemistry and relative configurations of the synthesized compounds were determined by 1D and 2D NMR spectroscopy and X-ray crystallography. The reaction was also performed using enantiomeric starting materials leading to enantiomeric quinazolinotriazolobenzodiazepine with an ee of 95%. The synthesis of 9H-benzo[f]pyrimido[1,2-d][1,2,3]triazolo[1,5-a][1,4]diazepinone, a new heterocyclic system, was achieved in a good yield using a retro Diels–Alder (RDA) procedure. Some compounds were tested for antiproliferative activities against five human cancer cell lines of gynecological.
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recent advances in the transformations of cycloalkane fused oxiranes and aziridines
Tetrahedron, 2017Co-Authors: Melinda Nonn, Attila Mario Remete, Ferenc Fulop, Lorand KissAbstract:Abstract This account highlights the most relevant transformations of cycloalkane-fused oxiranes and aziridines developed during the past decade with the intention to provide an overview of the ring-opening synthetic techniques towards different functionalized cycloalkanes in racemic or enantiomerically pure form. It focuses also on the regioselectivity/regiocontrol and enantioselectivity of ring-opening methodologies including unsymmetrical cycloalkane-fused oxiranes and aziridines.
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synthesis and structure of cycloalkane and norbornane condensed 6 aryl 1 2 4 5 tetrahydropyridazinones
Journal of Heterocyclic Chemistry, 2004Co-Authors: Ferenc Csende, Anasztarzia Hetenyi, Geza Stajer, Ferenc FulopAbstract:The C=N double bond of certain cis- or trans-cycloalkane and diexo- or diendo-norbornane-condensed pyridazinones was reduced with NaBH3CN. The cis- or trans nature of the starting cycloalkane derivatives was always retained in the saturated products, with a high degree of diastereoselectivity: the hydrogen on the new stereocenter and the annelational hydrogen next to the carbonyl always exhibited the same steric orientation. The stereostructures were determined by means of nmr measurements and confirmed by molecular modelling.
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synthesis and opioid binding activity of dermorphin analogues containing cyclic β amino acids
Neuropeptides, 1997Co-Authors: B Bozu, Ferenc Fulop, G K Toth, Geza Toth, Maria SzucsAbstract:In the present work, eight conformationally constrained analogues of the mu specific opioid peptide dermorphin were synthesized by replacing D-Ala2 with stereoisomers of beta-amino-cycloalkane or Cycloalkene carboxylic acids. The resulting peptides were tested for their potency to mu and delta opioid binding sites of rat brain membranes labelled with [3H]Tyr1-D-Ala2-MePhe4-Gly-ol, [3H]DAMGO and [3H]Ile5,6deltorphin, respectively. All of the new derivatives displayed highly attenuated binding to both receptor types, albeit the decrease in their potency seemed to be less in the case of delta binding. Trans position of the beta-amino groups resulted in higher binding affinities than that of the corresponding cis isomers, the latter being more flexible than the former. It is concluded that conformational constraints caused either by a rigid ring structure or cis isomers instead of D-Ala2 in dermorphin-derived peptides are unfavourable for binding activity to either opioid receptors. We propose that interaction of the larger heptapeptide derivatives of dermorphins with the mu receptor is distinct from that of the tetrapeptide morphiceptin.
Jun-ichi Anzai - One of the best experts on this subject based on the ideXlab platform.
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[3+3]Cycloalkyne dimers linked by an azo group: a stable cis-azo compound forms polymeric aggregates by nonplanar pi-pi interactions.
Journal of the American Chemical Society, 2003Co-Authors: Yuto Saiki, Tomonori Hoshi, Hiroki Sugiura, Keiichi Nakamura, Masahiko Yamaguchi, Jun-ichi AnzaiAbstract:We previously reported that the structure of the linker moiety controlled intramolecular and bimolecular aggregation of [3+3]cycloalkyne oligomers, which are cyclic acetylene derivatives containing helicenes. Here, novel [3+3]cycloalkyne dimers linked by the azo group are synthesized, and aggregation behaviors are studied, which turned out to be considerably different. The trans- and cis-azo compounds were synthesized by the oxidative coupling of a [3+3]cycloalkyne amine derivative, and the stereochemistry was determined by UV-vis spectroscopy. 1H NMR, CD, gel permeation chromatography analysis, and vapor pressure osmometry in chloroform revealed that the trans-isomer forms a strong and selective bimolecular aggregate. The cis-isomer forms a trimolecular aggregate at a concentration below 1 mM and a polymeric aggregate at above 1 mM. Unlike known diaryl azo compounds, these azo isomers do not interconvert when subjected to heating or irradiation. In contrast, a model compound lacking the cyclic helicene structure isomerizes readily.
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3 3 cycloalkyne dimers linked by an azo group a stable cis azo compound forms polymeric aggregates by nonplanar π π interactions
Journal of the American Chemical Society, 2003Co-Authors: Yuto Saiki, Tomonori Hoshi, Hiroki Sugiura, Keiichi Nakamura, Masahiko Yamaguchi, Jun-ichi AnzaiAbstract:We previously reported that the structure of the linker moiety controlled intramolecular and bimolecular aggregation of [3+3]cycloalkyne oligomers, which are cyclic acetylene derivatives containing helicenes. Here, novel [3+3]cycloalkyne dimers linked by the azo group are synthesized, and aggregation behaviors are studied, which turned out to be considerably different. The trans- and cis-azo compounds were synthesized by the oxidative coupling of a [3+3]cycloalkyne amine derivative, and the stereochemistry was determined by UV−vis spectroscopy. 1H NMR, CD, gel permeation chromatography analysis, and vapor pressure osmometry in chloroform revealed that the trans-isomer forms a strong and selective bimolecular aggregate. The cis-isomer forms a trimolecular aggregate at a concentration below 1 mM and a polymeric aggregate at above 1 mM. Unlike known diaryl azo compounds, these azo isomers do not interconvert when subjected to heating or irradiation. In contrast, a model compound lacking the cyclic helicene s...
Yuto Saiki - One of the best experts on this subject based on the ideXlab platform.
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[3+3]Cycloalkyne dimers linked by an azo group: a stable cis-azo compound forms polymeric aggregates by nonplanar pi-pi interactions.
Journal of the American Chemical Society, 2003Co-Authors: Yuto Saiki, Tomonori Hoshi, Hiroki Sugiura, Keiichi Nakamura, Masahiko Yamaguchi, Jun-ichi AnzaiAbstract:We previously reported that the structure of the linker moiety controlled intramolecular and bimolecular aggregation of [3+3]cycloalkyne oligomers, which are cyclic acetylene derivatives containing helicenes. Here, novel [3+3]cycloalkyne dimers linked by the azo group are synthesized, and aggregation behaviors are studied, which turned out to be considerably different. The trans- and cis-azo compounds were synthesized by the oxidative coupling of a [3+3]cycloalkyne amine derivative, and the stereochemistry was determined by UV-vis spectroscopy. 1H NMR, CD, gel permeation chromatography analysis, and vapor pressure osmometry in chloroform revealed that the trans-isomer forms a strong and selective bimolecular aggregate. The cis-isomer forms a trimolecular aggregate at a concentration below 1 mM and a polymeric aggregate at above 1 mM. Unlike known diaryl azo compounds, these azo isomers do not interconvert when subjected to heating or irradiation. In contrast, a model compound lacking the cyclic helicene structure isomerizes readily.
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3 3 cycloalkyne dimers linked by an azo group a stable cis azo compound forms polymeric aggregates by nonplanar π π interactions
Journal of the American Chemical Society, 2003Co-Authors: Yuto Saiki, Tomonori Hoshi, Hiroki Sugiura, Keiichi Nakamura, Masahiko Yamaguchi, Jun-ichi AnzaiAbstract:We previously reported that the structure of the linker moiety controlled intramolecular and bimolecular aggregation of [3+3]cycloalkyne oligomers, which are cyclic acetylene derivatives containing helicenes. Here, novel [3+3]cycloalkyne dimers linked by the azo group are synthesized, and aggregation behaviors are studied, which turned out to be considerably different. The trans- and cis-azo compounds were synthesized by the oxidative coupling of a [3+3]cycloalkyne amine derivative, and the stereochemistry was determined by UV−vis spectroscopy. 1H NMR, CD, gel permeation chromatography analysis, and vapor pressure osmometry in chloroform revealed that the trans-isomer forms a strong and selective bimolecular aggregate. The cis-isomer forms a trimolecular aggregate at a concentration below 1 mM and a polymeric aggregate at above 1 mM. Unlike known diaryl azo compounds, these azo isomers do not interconvert when subjected to heating or irradiation. In contrast, a model compound lacking the cyclic helicene s...
Hiroki Sugiura - One of the best experts on this subject based on the ideXlab platform.
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[3+3]Cycloalkyne dimers linked by an azo group: a stable cis-azo compound forms polymeric aggregates by nonplanar pi-pi interactions.
Journal of the American Chemical Society, 2003Co-Authors: Yuto Saiki, Tomonori Hoshi, Hiroki Sugiura, Keiichi Nakamura, Masahiko Yamaguchi, Jun-ichi AnzaiAbstract:We previously reported that the structure of the linker moiety controlled intramolecular and bimolecular aggregation of [3+3]cycloalkyne oligomers, which are cyclic acetylene derivatives containing helicenes. Here, novel [3+3]cycloalkyne dimers linked by the azo group are synthesized, and aggregation behaviors are studied, which turned out to be considerably different. The trans- and cis-azo compounds were synthesized by the oxidative coupling of a [3+3]cycloalkyne amine derivative, and the stereochemistry was determined by UV-vis spectroscopy. 1H NMR, CD, gel permeation chromatography analysis, and vapor pressure osmometry in chloroform revealed that the trans-isomer forms a strong and selective bimolecular aggregate. The cis-isomer forms a trimolecular aggregate at a concentration below 1 mM and a polymeric aggregate at above 1 mM. Unlike known diaryl azo compounds, these azo isomers do not interconvert when subjected to heating or irradiation. In contrast, a model compound lacking the cyclic helicene structure isomerizes readily.
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3 3 cycloalkyne dimers linked by an azo group a stable cis azo compound forms polymeric aggregates by nonplanar π π interactions
Journal of the American Chemical Society, 2003Co-Authors: Yuto Saiki, Tomonori Hoshi, Hiroki Sugiura, Keiichi Nakamura, Masahiko Yamaguchi, Jun-ichi AnzaiAbstract:We previously reported that the structure of the linker moiety controlled intramolecular and bimolecular aggregation of [3+3]cycloalkyne oligomers, which are cyclic acetylene derivatives containing helicenes. Here, novel [3+3]cycloalkyne dimers linked by the azo group are synthesized, and aggregation behaviors are studied, which turned out to be considerably different. The trans- and cis-azo compounds were synthesized by the oxidative coupling of a [3+3]cycloalkyne amine derivative, and the stereochemistry was determined by UV−vis spectroscopy. 1H NMR, CD, gel permeation chromatography analysis, and vapor pressure osmometry in chloroform revealed that the trans-isomer forms a strong and selective bimolecular aggregate. The cis-isomer forms a trimolecular aggregate at a concentration below 1 mM and a polymeric aggregate at above 1 mM. Unlike known diaryl azo compounds, these azo isomers do not interconvert when subjected to heating or irradiation. In contrast, a model compound lacking the cyclic helicene s...
Tomonori Hoshi - One of the best experts on this subject based on the ideXlab platform.
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[3+3]Cycloalkyne dimers linked by an azo group: a stable cis-azo compound forms polymeric aggregates by nonplanar pi-pi interactions.
Journal of the American Chemical Society, 2003Co-Authors: Yuto Saiki, Tomonori Hoshi, Hiroki Sugiura, Keiichi Nakamura, Masahiko Yamaguchi, Jun-ichi AnzaiAbstract:We previously reported that the structure of the linker moiety controlled intramolecular and bimolecular aggregation of [3+3]cycloalkyne oligomers, which are cyclic acetylene derivatives containing helicenes. Here, novel [3+3]cycloalkyne dimers linked by the azo group are synthesized, and aggregation behaviors are studied, which turned out to be considerably different. The trans- and cis-azo compounds were synthesized by the oxidative coupling of a [3+3]cycloalkyne amine derivative, and the stereochemistry was determined by UV-vis spectroscopy. 1H NMR, CD, gel permeation chromatography analysis, and vapor pressure osmometry in chloroform revealed that the trans-isomer forms a strong and selective bimolecular aggregate. The cis-isomer forms a trimolecular aggregate at a concentration below 1 mM and a polymeric aggregate at above 1 mM. Unlike known diaryl azo compounds, these azo isomers do not interconvert when subjected to heating or irradiation. In contrast, a model compound lacking the cyclic helicene structure isomerizes readily.
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3 3 cycloalkyne dimers linked by an azo group a stable cis azo compound forms polymeric aggregates by nonplanar π π interactions
Journal of the American Chemical Society, 2003Co-Authors: Yuto Saiki, Tomonori Hoshi, Hiroki Sugiura, Keiichi Nakamura, Masahiko Yamaguchi, Jun-ichi AnzaiAbstract:We previously reported that the structure of the linker moiety controlled intramolecular and bimolecular aggregation of [3+3]cycloalkyne oligomers, which are cyclic acetylene derivatives containing helicenes. Here, novel [3+3]cycloalkyne dimers linked by the azo group are synthesized, and aggregation behaviors are studied, which turned out to be considerably different. The trans- and cis-azo compounds were synthesized by the oxidative coupling of a [3+3]cycloalkyne amine derivative, and the stereochemistry was determined by UV−vis spectroscopy. 1H NMR, CD, gel permeation chromatography analysis, and vapor pressure osmometry in chloroform revealed that the trans-isomer forms a strong and selective bimolecular aggregate. The cis-isomer forms a trimolecular aggregate at a concentration below 1 mM and a polymeric aggregate at above 1 mM. Unlike known diaryl azo compounds, these azo isomers do not interconvert when subjected to heating or irradiation. In contrast, a model compound lacking the cyclic helicene s...
