https://pubs.rsc.org/en/content/articlepdf/2019/NP/C8NP00092A

Marine natural products.

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.

/pdf/toxic-cyanobacteria-in-water-a-guide-to-their-public-health-2y64v55hv1.pdf

Toxic cyanobacteria in water: a guide to their public health consequences, monitoring and management.

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

Natural product synthesis using multicomponent reaction strategies.

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.

/pdf/antibacterial-free-fatty-acids-activities-mechanisms-of-5ew888s9bz.pdf

Antibacterial free fatty acids: activities, mechanisms of action and biotechnological potential

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

The assignment of absolute configuration by NMR

Acetylsanadaol, a diterpene having a novel skeleton, from the brown alga,

Bicyclic diterpenes from two species of brown algae of the dictyotaceae

New dihydrophenanthrapyrans from cedrelinga catenaeformis

The 1H and 13C NMR spectra were assigned for a series of N-alkyl-α-methoxycarbonylmethanimine N-oxides and N-methyl-α-phenyl-,N-methyl-α-(pentamethylphenyl)- and N-phenyl-α-benzoyl-methanimine N-oxides. Data are presented which allow the assignment of their configurations.

1H and 13C NMR spectra of several (E)- and (Z)-aldonitrones

Mass culture of an axenic clone ofMicrocystis viridis (NIES-102) was carried out, and three toxins were isolated from the cell. Structure elucidation of one of the toxins, designated cyanoviridin RR (microcystin RR), was performed mainly by means of modern NMR techniques. Cyanoviridin RR was a cyclic heptapeptide consisting of seven amino acids, Adda, l-arginine, erthro-β-methyl-aspartic acid, l-arginine, d-alanine, N-methyldehydroalanine, and d-glutamic acid. Structurally, this toxin belongs to the cyanoginosins already isolated fromM. aeruginosa.

Hiroshi Kakisawa

Papers

Acetylsanadaol, a diterpene having a novel skeleton, from the brown alga,

Bicyclic diterpenes from two species of brown algae of the dictyotaceae

New dihydrophenanthrapyrans from cedrelinga catenaeformis

1H and 13C NMR spectra of several (E)- and (Z)-aldonitrones

Structure of cyanoviridin RR, a toxin from the blue-green alga,Microcystis viridis