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Hiroshi Kakisawa

Bio: Hiroshi Kakisawa is an academic researcher from University of Tsukuba. The author has contributed to research in topics: Diterpene & Absolute configuration. The author has an hindex of 14, co-authored 26 publications receiving 837 citations.

Papers
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Journal ArticleDOI
TL;DR: In this article, the absolute configurations of marine diterpenes, 7 and 8, were elucidated by means of Mosher's method using 1H NMR spectroscopy at 500 MHz.

156 citations

Journal ArticleDOI
TL;DR: In this paper, the stereochemistry of the cembranolides isolated from the soft coral Sinularia mayi has been elucidated by means of 2D NMR spectroscopy and X-ray crystallography.

123 citations

Journal ArticleDOI
TL;DR: The tetraunsaturated fatty acid exterminated toxic red tide planktons such as Chattonella antiqua at 1 ppm concentration.

91 citations

Journal ArticleDOI
TL;DR: In this article, the utility of modified Mosher's method is examined by applying it to three marine cembranolides, 2, 3, and 4, with known absolute configurations, and it is concluded that the method can be safely used for the, compounds with a sterically unhindered OH group, but care must be taken in applying to the secondary alcohols with the OH group located in a crowded environment.

84 citations

Journal ArticleDOI
TL;DR: A toxin, named as cyanoviridin RR, has been isolated from the cyanobacterium Microcystis viridis and the structure of the toxin has been determined by modern NMR techniques such as the HMBC spectrum.

78 citations


Cited by
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Journal ArticleDOI
TL;DR: This review covers the literature published in 2014 for marine natural products, with 1116 citations referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms.

4,649 citations

Reference BookDOI
11 Feb 1999
TL;DR: The state of knowledge regarding the principal considerations in the design of programmes and studies for monitoring water resources and supplies and describes the approaches and procedures used as mentioned in this paper, and the information needed for protecting drinking water sources and recreational water bodies from the health hazards caused by cyanobacteria and their toxins.
Abstract: This book describes the present state of knowledge regarding the impact of cyanobacteria on health through the use of water. It considers aspects of risk management and details the information needed for protecting drinking water sources and recreational water bodies from the health hazards caused by cyanobacteria and their toxins. It also outlines the state of knowledge regarding the principal considerations in the design of programmes and studies for monitoring water resources and supplies and describes the approaches and procedures used. The development of this publication was guided by the recommendations of several expert meetings concerning drinking water (Geneva, December 1995; Bad Elster, June 1996) and recreational water (Bad Elster, June 1996; St Helier, May 1997). An expert meeting in Bad Elster, April 1997, critically reviewed the literature concerning the toxicity of cyanotoxins and developed the scope and content of this book. A draft manuscript was reviewed at an editorial meeting in November 1997, and a further draft was reviewed by the working group responsible for updating the Guidelines for Drinkingwater Quality in March 1998.

3,131 citations

Journal ArticleDOI
TL;DR: The preparation of urea by Wöhler constituted a landmark achievement in organic chemistry, and it laid the ground for the early days of target-oriented organic synthesis, a task deemed inconceivable by early practitioners.
Abstract: The preparation of urea by Wöhler constituted a landmark achievement in organic chemistry, and it laid the ground for the early days of target-oriented organic synthesis.1 Since then, significant progress has been achieved in this discipline; many powerful single bond forming reactions and asymmetric variants have been developed. These discoveries have paved the way for the stereoselective assembly of complex organic molecules, a task deemed inconceivable by early practitioners. A great many strategies were invented by chemists in order to facilitate the synthesis of complex natural products.2 One avenue in emulating nature’s efficiency would * To whom correspondence should be addressed. E-mail: dennis.hall@ ualberta.ca. † Novartis Institute for Biomedical Research. ‡ Department of Chemistry, University of Alberta. Chem. Rev. 2009, 109, 4439–4486 4439

1,374 citations

Journal ArticleDOI
TL;DR: Their broad spectrum of activity, non-specific mode of action and safety makes them attractive as antibacterial agents for various applications in medicine, agriculture and food preservation, especially where the use of conventional antibiotics is undesirable or prohibited.
Abstract: Amongst the diverse and potent biological activities of free fatty acids (FFAs) is the ability to kill or inhibit the growth of bacteria. The antibacterial properties of FFAs are used by many organisms to defend against parasitic or pathogenic bacteria. Whilst their antibacterial mode of action is still poorly understood, the prime target of FFA action is the cell membrane, where FFAs disrupt the electron transport chain and oxidative phosphorylation. Besides interfering with cellular energy production, FFA action may also result from the inhibition of enzyme activity, impairment of nutrient uptake, generation of peroxidation and auto-oxidation degradation products or direct lysis of bacterial cells. Their broad spectrum of activity, non-specific mode of action and safety makes them attractive as antibacterial agents for various applications in medicine, agriculture and food preservation, especially where the use of conventional antibiotics is undesirable or prohibited. Moreover, the evolution of inducible FFA-resistant phenotypes is less problematic than with conventional antibiotics. The potential for commercial or biomedical exploitation of antibacterial FFAs, especially for those from natural sources, is discussed.

1,075 citations

Journal ArticleDOI
TL;DR: In this paper, the application of (S)-1,10-binaphthyl-2,20-diol as NMR chiral solvating agent (CSA) for omeprazole, and three of its analogs (lanso-, panto-, and rabe-prazole) was investigated.
Abstract: The application of (S)-1,10-binaphthyl-2,20-diol as NMR chiral solvating agent (CSA) for omeprazole, and three of its analogs (lanso-, panto-, and rabe-prazole) was investigated. The formation of diastereomeric host–guest complexes in solution between the CSA and the racemic substrates produced sufficient NMR signal splitting for the determination of enantiomeric excesses by Hor F-NMR spectroscopy. Using of hydrophobic deuterated solvents was mandatory for obtaining good enantiodiscrimination, thus suggesting the importance of intermolecular hydrogen bonds in the stabilization of the complexes. The method was applied to the fast quantification of the enantiomeric purity of in-process samples of S-omeprazole. Chirality 00:000–000, 2009. VC 2009

885 citations