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Junichi Kobayashi - One of the best experts on this subject based on the ideXlab platform.
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hyrtimomines Indole Alkaloids from okinawan marine sponges hyrtios spp
ChemInform, 2014Co-Authors: Naonobu Tanaka, Rei Momose, Azusa Takahashinakaguchi, Tohru Gonoi, Jane Fromont, Junichi KobayashiAbstract:Six new Indole Alkaloids, hyrtimomines F-K, are isolated and screened for their antimicrobial activities.
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hyrtimomines Indole Alkaloids from okinawan marine sponges hyrtios spp
Tetrahedron, 2014Co-Authors: Naonobu Tanaka, Rei Momose, Azusa Takahashinakaguchi, Tohru Gonoi, Jane Fromont, Junichi KobayashiAbstract:Abstract Six new Indole Alkaloids, hyrtimomines F–K (1–6), were isolated from Okinawan marine sponges Hyrtios spp. The structures of 1–6 were elucidated on the basis of spectroscopic analysis. Hyrtimomine F (1) is a structurally unique bisIndole alkaloid possessing an α-keto-ɛ-caprolactam ring, while hyrtimomine G (2) is a symmetrical bisIndole alkaloid. Hyrtimomines H–K (3–6) are Indole Alkaloids possessing β-carboline skeleton with an imidazolium unit. Antimicrobial activities of hyrtimomines F–K (1–6) were evaluated.
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Subincanadines A-C, novel quaternary Indole Alkaloids from Aspidosperma subincanum.
The Journal of Organic Chemistry, 2002Co-Authors: Junichi Kobayashi, Mitsuhiro Sekiguchi, Sayaka Shimamoto, Hideyuki Shigemori, Haruaki Ishiyama, Ayumi OhsakiAbstract:Three novel quaternary Indole Alkaloids with an unprecedented 1-azoniatricyclo[4.3.3.01,5]undecane moiety, subincanadines A−C (1−3), as well as two new Indole Alkaloids with a 1-azabicyclo[5.2.2]undecane moiety, subincanadines D (4) and E (5), and a new Indole alkaloid with a 1-azabicyclo[4.3.1]decane moiety, subincanadine F (6), have been isolated from the barks of Aspidosperma subincanum Mart, and the structures of 1−6 and the stereochemistry of 1−3 were elucidated by spectroscopic data and chemical means.
Naonobu Tanaka - One of the best experts on this subject based on the ideXlab platform.
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hyrtimomines Indole Alkaloids from okinawan marine sponges hyrtios spp
ChemInform, 2014Co-Authors: Naonobu Tanaka, Rei Momose, Azusa Takahashinakaguchi, Tohru Gonoi, Jane Fromont, Junichi KobayashiAbstract:Six new Indole Alkaloids, hyrtimomines F-K, are isolated and screened for their antimicrobial activities.
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hyrtimomines Indole Alkaloids from okinawan marine sponges hyrtios spp
Tetrahedron, 2014Co-Authors: Naonobu Tanaka, Rei Momose, Azusa Takahashinakaguchi, Tohru Gonoi, Jane Fromont, Junichi KobayashiAbstract:Abstract Six new Indole Alkaloids, hyrtimomines F–K (1–6), were isolated from Okinawan marine sponges Hyrtios spp. The structures of 1–6 were elucidated on the basis of spectroscopic analysis. Hyrtimomine F (1) is a structurally unique bisIndole alkaloid possessing an α-keto-ɛ-caprolactam ring, while hyrtimomine G (2) is a symmetrical bisIndole alkaloid. Hyrtimomines H–K (3–6) are Indole Alkaloids possessing β-carboline skeleton with an imidazolium unit. Antimicrobial activities of hyrtimomines F–K (1–6) were evaluated.
Yu Zhang - One of the best experts on this subject based on the ideXlab platform.
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Melotenuines A-E, cytotoxic monoterpenoid Indole Alkaloids from Melodinus tenuicaudatus.
Fitoterapia, 2019Co-Authors: Jian-wen Liu, Yu Zhang, Xiao-jiang Hao, Zong-qing Huo, Qian Zhao, Yu ZhangAbstract:Abstract Five new monoterpenoid Indole Alkaloids, melotenuines A-E (1–5), along with 18 known Indole Alkaloids, were isolated from the twigs and leaves of Melodinus tenuicaudatus. The structures of the new Alkaloids were determined by a combination of MS, NMR and ECD analysis. Melotenuine A (1) represents the first example of aspidosperma-meloscandonine type bisIndole Alkaloids characterized by a methylene bridge between the two monomers, while melotenuine B (2) possessed a rare eburnamine-melsocandonine skeleton. All of the new Indole Alkaloids were evaluated for in vitro cytotoxicities against five human cancer cell lines. Among them, alkaloid 4 showed specific cytotoxicity against HL-60 cell line with IC50 value (5.15 ± 0.16 μM) comparable with that of positive control.
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two new monoterpenoid Indole Alkaloids from tabernaemontana divaricata
Natural Product Research, 2019Co-Authors: Yuxi Yuan, Huansha Yuwen, Hongping He, Yu ZhangAbstract:AbstractTwo new monoterpenoid Indole Alkaloids, tabervarines A (1) and B (2), along with seven known monoterpenoid Indole Alkaloids, were isolated from the methanol extract of the twigs and leaves of Tabernaemontana divaricata. The structures including the absolute configurations of the new Alkaloids were elucidated based on MS, NMR, and ECD calculation. The in vitro cytotoxic activities of the isolated Alkaloids against several human cancer cell lines were also evaluated.
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Antiproliferative Aspidosperma-Type Monoterpenoid Indole Alkaloids from Bousigonia mekongensis Inhibit Tubulin Polymerization
MDPI AG, 2019Co-Authors: Yu Zhang, Ling-li Guo, Masuo Goto, Akifumi Oda, Pei-ling Hsu, Susan L. Morris-natschke, Ernest Hamel, Kuo-hsiung Lee, Xiao-jiang HaoAbstract:Monoterpenoid Indole Alkaloids are structurally diverse natural products found in plants of the family Apocynaceae. Among them, vincristine and its derivatives are well known for their anticancer activity. Bousigonia mekongensis, a species in this family, contains various monoterpenoid Indole Alkaloids. In the current study, fourteen known aspidosperma-type monoterpenoid Indole Alkaloids (1–14) were isolated and identified from a methanol extract of the twigs and leaves of B. mekongensis for the first time. Among them, compounds 3, 6, 9, and 13 exhibited similar antiproliferative activity spectra against A549, KB, and multidrug-resistant (MDR) KB subline KB-VIN cells with IC50 values ranging from 0.5–0.9 μM. The above Alkaloids efficiently induced cell cycle arrest at the G2/M phase by inhibiting tubulin polymerization as well as mitotic bipolar spindle formation. Computer modeling studies indicated that compound 7 likely forms a hydrogen bond (H-bond) with α- or β-tubulin at the colchicine site. Evaluation of the antiproliferative effects and SAR analysis suggested that a 14,15-double bond or 3α-acetonyl group is critical for enhanced antiproliferative activity. Mechanism of action studies demonstrated for the first time that compounds 3, 4, 6, 7, and 13 efficiently induce cell cycle arrest at G2/M by inhibiting tubulin polymerization by binding to the colchicine site
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Cytotoxic Indole Alkaloids from Melodinus khasianus and Melodinus tenuicaudatus.
Fitoterapia, 2018Co-Authors: Duo-zhi Chen, Xiao Ding, Yu Zhang, Yu Zhang, Xiao-jiang HaoAbstract:Abstract Four new Indole Alkaloids, melodinusines A-D (1, 2, 6, and 7), along with 26 known Indole Alkaloids, were isolated from Melodinus tenuicaudatus and Melodinus khasianus (Melodinus genus). Among them, 1 and 2 are aspidospermine-aspidospermine-type bisIndole Alkaloids while 7 is a novel melodinus-type alkaloid. Their structures were established on the basis of comprehensive spectroscopic data analysis and the structure of 7 was further confirmed by single-crystal X-ray diffraction analysis. Their cytotoxic activities against five human cancer cell lines, HL-60, SMMC-7721, A-549, MCF-7, and SW480 were also evaluated.
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Melohenryines A and B, two new Indole Alkaloids from Melodinus henryi
Phytochemistry Letters, 2017Co-Authors: Ling-li Guo, Yu Zhang, Yu-xi Yuan, Yu Zhang, Yuxi Yuan, Xiao-jiang HaoAbstract:Two new monoterpenoid Indole Alkaloids, melohenryines A and B (1 and 2), along with six known Indole Alkaloids, were isolated from the twigs and leaves of Melodinus henryi. Structures of the new Alkaloids were established by extensive spectroscopic techniques including NMR spectroscopy and mass spectrometry. Melohenryine A (1) represents the first example of monoterpenoid Indole Alkaloids characterized an ester carbonyl group at C-19 position. All of the new compounds were evaluated for in vitro cytotoxicity against several human cancer cell lines.
Rei Momose - One of the best experts on this subject based on the ideXlab platform.
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hyrtimomines Indole Alkaloids from okinawan marine sponges hyrtios spp
ChemInform, 2014Co-Authors: Naonobu Tanaka, Rei Momose, Azusa Takahashinakaguchi, Tohru Gonoi, Jane Fromont, Junichi KobayashiAbstract:Six new Indole Alkaloids, hyrtimomines F-K, are isolated and screened for their antimicrobial activities.
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hyrtimomines Indole Alkaloids from okinawan marine sponges hyrtios spp
Tetrahedron, 2014Co-Authors: Naonobu Tanaka, Rei Momose, Azusa Takahashinakaguchi, Tohru Gonoi, Jane Fromont, Junichi KobayashiAbstract:Abstract Six new Indole Alkaloids, hyrtimomines F–K (1–6), were isolated from Okinawan marine sponges Hyrtios spp. The structures of 1–6 were elucidated on the basis of spectroscopic analysis. Hyrtimomine F (1) is a structurally unique bisIndole alkaloid possessing an α-keto-ɛ-caprolactam ring, while hyrtimomine G (2) is a symmetrical bisIndole alkaloid. Hyrtimomines H–K (3–6) are Indole Alkaloids possessing β-carboline skeleton with an imidazolium unit. Antimicrobial activities of hyrtimomines F–K (1–6) were evaluated.
Jane Fromont - One of the best experts on this subject based on the ideXlab platform.
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hyrtimomines Indole Alkaloids from okinawan marine sponges hyrtios spp
ChemInform, 2014Co-Authors: Naonobu Tanaka, Rei Momose, Azusa Takahashinakaguchi, Tohru Gonoi, Jane Fromont, Junichi KobayashiAbstract:Six new Indole Alkaloids, hyrtimomines F-K, are isolated and screened for their antimicrobial activities.
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hyrtimomines Indole Alkaloids from okinawan marine sponges hyrtios spp
Tetrahedron, 2014Co-Authors: Naonobu Tanaka, Rei Momose, Azusa Takahashinakaguchi, Tohru Gonoi, Jane Fromont, Junichi KobayashiAbstract:Abstract Six new Indole Alkaloids, hyrtimomines F–K (1–6), were isolated from Okinawan marine sponges Hyrtios spp. The structures of 1–6 were elucidated on the basis of spectroscopic analysis. Hyrtimomine F (1) is a structurally unique bisIndole alkaloid possessing an α-keto-ɛ-caprolactam ring, while hyrtimomine G (2) is a symmetrical bisIndole alkaloid. Hyrtimomines H–K (3–6) are Indole Alkaloids possessing β-carboline skeleton with an imidazolium unit. Antimicrobial activities of hyrtimomines F–K (1–6) were evaluated.