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4. sj-docx-1-npx-10.1177_1934578X211053202 - Supplemental material for A Novel Trimeric Triterpene From Chisocheton ceramicus Miq

Author

Nugroho, Alfarius Eko, Okabe, Marika, Hirasawa, Yusuke, Wong, Chin Piow, Kaneda, Toshio, Tougan, Takahiro, Horii, Toshihiro, and Morita, Hiroshi

Subjects
FOS: Clinical medicine, 111599 Pharmacology and Pharmaceutical Sciences not elsewhere classified
Abstract

Supplemental material, sj-docx-1-npx-10.1177_1934578X211053202 for A Novel Trimeric Triterpene From Chisocheton ceramicus Miq. by Alfarius Eko Nugroho, Marika Okabe, Yusuke Hirasawa and Chin Piow Wong, Toshio Kaneda, Takahiro Tougan, Toshihiro Horii, Hiroshi Morita in Natural Product Communications

Published
2021
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5. Lyconadin A, a novel alkaloid from Lycopodium complanatum

Author

Kobayashi, Jun'ichi, Hirasawa, Yusuke, Yoshida, Naotoshi, and Morita, Hiroshi

Subjects
Chemistry, Organic -- Research, Alkaloids -- Physiological aspects, Club-mosses -- Physiological aspects, Carbon -- Physiological aspects, Nitrogen -- Physiological aspects, Biological sciences, Chemistry
Abstract

Research has been conducted on lyconadin A, an alkaloid with an unprecedented skeleton from the club moss Lycopodium complanatum. The isolation and structure elucidation of this lyconadin have been investigated and discussed.

Published
2001

8. Bisnicalaterines B and C, atropisomeric bisindole alkaloids from C, showing vasorelaxant activity

Author

Hirasawa, Yusuke, Hadi, A. Hamid A., Litaudon, Marc, Morita, Hiroshi, Kawahara, Nobuo, Goda, Yukihiro, Awang, Khalijah, Nugroho, Alfarius E., Sugai, Masatomo, Zaima, Kazumasa, and Hara, Mayumi

Subjects
Carbon compounds -- Chemical properties, Carbon compounds -- Structure, Alkaloids -- Structure, Alkaloids -- Chemical properties, Biological sciences, Chemistry
Abstract

Two new bisindole alkaloids, bisnicalaterines B and C consisting of an eburnane and a corynanthe type, are isolated from the bark of Hunteria zeylanica and their absolute structures are determined. Bisnicalaterines B and C have displayed potent vasorelaxant activity on isolated rat aorta.

Published
2010

9. Himeradine A, a novel C (sub)27 N (sub)3 -type alkaloid from Lycopodium chinense

Author

Morita, Hiroshi, Hirasawa, Yusuke, and Kobayashi, Jun'ichi

Subjects
Chemistry, Organic -- Research, Organic compounds -- Composition, Alkaloids, Stereochemistry -- Research, Carbon compounds, Nitrogen compounds, Biological sciences, Chemistry
Abstract

Research has been conducted on C (sub)27 N (sub)3 -type alkaloid from Lycopodium chinense which consists of fastigiatine-type skeleton and quinolizidine moiety himeradine A. The authors describe the isolation of this compound and the study of its structure and stereochemistry.

Published
2003

10. Neolamarckines A and B, new indole alkaloids from Neolamarckia cadamba

Author

Qureshi, Ahmad Kaleem, Mukhtar, Mat Ropi, Hirasawa, Yusuke, Hosoya, Takahiro, Nugroho, Alfarius Eko, Morita, Hiroshi, Shirota, Osamu, Mohamad, Khalit, Hadi, a Hamid A, Litaudon, Marc, Awang, Khalijah, Institut de Chimie des Substances Naturelles (ICSN), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), and Brunet, Jocelyne

Subjects
Plant Leaves, Mice, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Cell Survival, Plant Extracts, Animals, Rubiaceae, [CHIM.ORGA] Chemical Sciences/Organic chemistry, Cell Line, Indole Alkaloids
Abstract

International audience; Two new indole alkaloids, neolamarckines A and B (1, 2) were isolated from the leaves of Neolamarckia cadamba (Rubiaceae). Structural elucidation of 1 and 2 was performed by combination of 2D-NMR and circular dichroism (CD) spectra, and chemical correlations. Neolamarckine A (1) showed inhibition of inducible nitric oxide synthase (iNOS) dose dependently.

Published
2011

11. Vasorelaxant activity of indole alkaloids from Tabernaemontana dichotoma.

Author

Zaima, Kazumasa, Koga, Ikumi, Iwasawa, Nobuhide, Hosoya, Takahiro, Hirasawa, Yusuke, Kaneda, Toshio, Ismail, Intan Safinar, Lajis, Nordin, Morita, Hiroshi, Zaima, Kazumasa, Koga, Ikumi, Iwasawa, Nobuhide, Hosoya, Takahiro, Hirasawa, Yusuke, Kaneda, Toshio, Ismail, Intan Safinar, Lajis, Nordin, and Morita, Hiroshi

Abstract

The aim of this study was to search for bioactive natural products from medicinal plants targeting vasorelaxant activity and we found the methanol extract from bark of Tabernaemontana dichotoma showed vasorelaxant activity on rat aorta. We isolated eight indole alkaloids including 10-methoxyalstonerine (1), a new macroline type indole alkaloid, from bark of T. dichotoma. These were respectively identified as 10-methoxyaffinisine (2), lochnerine (3), cathafoline (4), (−)-alstonerine (5), 19,20-dehydro-10-methoxytalcarpine (6), alstonisine (7), and alstonal (8) based on spectroscopic analysis. Among them, sarpagine type (2 and 3), akuammiline type (4), and macroline oxindole type (7 and 8) showed potent vasorelaxant activity. Mechanism of action on vasorelaxant activity of 10-methoxyaffinisine (2), cathafoline (4), and alstonisine (7) was clarified. Effects of 10-methoxyaffinisine (2), cathafoline (4), and alstonisine (7) were partially mediated the NO release from endothelial cells. Furthermore, 10-methoxyaffinisine (2) and alstonisine (7) attribute to the inhibitory effect of VDC and ROC, and cathafoline (4) have inhibitory effect on Ca2+ influx via ROC. In addition, 10-methoxyaffinisine (2) as a major compound from bark of T. dichotoma showed hypotensive effect on normotensive rats in vivo.

Published
2013

12. New vasorelaxant indole alkaloids, villocarines A-D from Uncaria villosa.

Author

Matsuo, Hirotaka, Okamoto, Ryuichi, Zaima, Kazumasa, Hirasawa, Yusuke, Ismail, Intan Safinar, Lajis, Md. Nordin, Morita, Hiroshi, Matsuo, Hirotaka, Okamoto, Ryuichi, Zaima, Kazumasa, Hirasawa, Yusuke, Ismail, Intan Safinar, Lajis, Md. Nordin, and Morita, Hiroshi

Abstract

Villocarines A–D (1–4), four new indole alkaloids have been isolated from the leaves of Uncaria villosa (Rubiaceae) and their structures were elucidated by 2D NMR methods and chemical correlations. Villocarine A (1) showed vasorelaxation activity against rat aortic ring and showed inhibition effect on vasocontraction of depolarized aorta with high concentration potassium, and also inhibition effect on phenylephrine (PE)-induced contraction in the presence of nicardipine in a Ca2+ concentration-dependent manner. The vasorelaxant effect by 1 might be attributed mainly to inhibition of calcium influx from extracellular space through voltage-dependent calcium channels (VDC) and/or receptor-operated Ca2+-channels (ROC), and also partly mediated through the increased release of NO from endothelial cells and opening of voltage-gated K+-channels.

Published
2011

13. Chrotacumines A-D, chromone alkaloids from Dysoxylum acutangulum

Author

Ismail, Intan Safinar, Nagakura, Yuta, Hirasawa, Yusuke, Hosoya, Takahiro, Mohd Lazim, Mohd Izwan, Lajis, Md. Nordin, Shiro, Motoo, Morita, Hiroshi, Ismail, Intan Safinar, Nagakura, Yuta, Hirasawa, Yusuke, Hosoya, Takahiro, Mohd Lazim, Mohd Izwan, Lajis, Md. Nordin, Shiro, Motoo, and Morita, Hiroshi

Abstract

Four new chromone alkaloids, chrotacumines A-D (1-4), consisting of a 5,7-dihydroxy-2-methylchromone, an N-Me piperidine ring, and an ester side chain were isolated from Dysoxylum acutangulum, and their structures including absolute configurations were elucidated on the basis of spectroscopic data interpretation including 2D NMR, CD spectra, and X-ray analysis. The known compound rohitukine (5) showed moderate cytotoxicity against human HL-60 promyelocytic leukemia and HCT-116 colon cancer cells.

Published
2009

14. Acutaxylines A and B, two novel triterpenes from Dysoxylum acutangulum

Author

Ismail, Intan Safinar, Nagakura, Yuta, Hirasawa, Yusuke, Hosoya, Takahiro, Mohd Lazim, Mohd Izwan, Lajis, Md. Nordin, Morita, Hiroshi, Ismail, Intan Safinar, Nagakura, Yuta, Hirasawa, Yusuke, Hosoya, Takahiro, Mohd Lazim, Mohd Izwan, Lajis, Md. Nordin, and Morita, Hiroshi

Abstract

Two novel triterpenes, acutaxylines A (1) and B (2) consisting of a cyclopentenone side chain at C-17 and an oxepan-2-ol, were isolated from the leaves of Dysoxylum acutangulum. The relative stereochemistry of 1 and 2 was determined by NOESY correlations. Acutaxyline B showed moderate cytotoxicity against human blood premyelocytic leukemia cells.

Published
2009

19. Ceramicines E-I, New Limonoids from Chisocheton ceramicus

Author

Wong, Chin Piow, primary, Shimada, Misae, additional, Nagakura, Yuta, additional, Nugroho, Alfarius Eko, additional, Hirasawa, Yusuke, additional, Kaneda, Toshio, additional, Awang, Khalijah, additional, Hadi, A. Hamid A., additional, Mohamad, Khalit, additional, Shiro, Motoo, additional, and Morita, Hiroshi, additional

Published
2011
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26. Himeradine A, a Novel C[sub 27]N[sub 3]-Type Alkaloid from Lycopodium chinense.

Author

Morita, Hiroshi, Hirasawa, Yusuke, and Kobayashi, Jun'ichi

Subjects
*OXIDATION, *ORGANIC chemistry
Abstract

A novel C[sub 27]N[sub 3]-type Lycopodium alkaloid consisting of a fastigiatine-type skeleton (C[sub 16]N[sub 2]) and a quinolizidine moiety (C[sub 11]N), himeradine A (1), has been isolated from the club moss Lycopodium chinense, and the structure and relative stereochemistry were elucidated on the basis of spectroscopic data. [ABSTRACT FROM AUTHOR]

Published
2003
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27. Neolamarckines A and B, new indole alkaloids from Neolamarckia cadamba.

Author

Qureshi AK, Mukhtar MR, Hirasawa Y, Hosoya T, Nugroho AE, Morita H, Shirota O, Mohamad K, Hadi AH, Litaudon M, and Awang K

Subjects
Animals, Cell Line, Cell Survival drug effects, Cell Survival physiology, Indole Alkaloids chemistry, Indole Alkaloids pharmacology, Mice, Plant Extracts chemistry, Plant Extracts pharmacology, Indole Alkaloids isolation & purification, Plant Extracts isolation & purification, Plant Leaves, Rubiaceae chemistry
Abstract

Two new indole alkaloids, neolamarckines A and B (1, 2) were isolated from the leaves of Neolamarckia cadamba (Rubiaceae). Structural elucidation of 1 and 2 was performed by combination of 2D-NMR and circular dichroism (CD) spectra, and chemical correlations. Neolamarckine A (1) showed inhibition of inducible nitric oxide synthase (iNOS) dose dependently., (© 2011 Pharmaceutical Society of Japan)

Published
2011
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28. Bulk heterojunction photoelectrochemical cells consisting of oxotitanyl phthalocyanine nanoporous films and I(3)(-)/I(-) redox couple.

Author

Hoshino K, Hirasawa Y, Kim SK, Saji T, and Katano J

Abstract

Photoelectrochemical cells based on oxotitanylphthalocyanine (TiOPc) films and an I(3)(-)/I(-) redox couple have been constructed. The TiOPc films were prepared on an indium-tin oxide coated glass plate (ITO) by the micellar disruption method and characterized by their unique nanoporous structure. A photocurrent action spectrum for input radiation directed through the ITO/TiOPc film, film-thickness dependence, and morphological investigation revealed that the cells consisted of a bulk heterojunction formed between the nanoporous TiOPc films and the liquid I3-/I- electrolyte, resulting in a larger short-circuit current (J(sc)= 2.1 mA/cm(2)), open-circuit voltage (V(oc)= 0.11 V), fill factor (ff= 0.31), and hence a larger energy conversion efficiency (eta= 0.13% for an incident white-light intensity of 53 mW/cm2) than the bilayer structure composed of the vaccum-evaporated TiOPc compact film and the I(3)(-)/I(-) electrolyte (J(sc)= 0.16 mA/cm(2), V(oc)= 0.018 V, ff = 0.27, and eta = (1.5 x 10(-3)%).

Published
2006
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