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Showing papers in "ChemInform in 1983"


Journal ArticleDOI
TL;DR: The physical properties, aqueous equilibria, and kinetics of CO2 and its hydrolysis products are discussed briefly in this paper, where the procedures for the preparation of metal carbonato complexes, their spectral characteristics, and their x-ray crystallographic structures are tabulated.
Abstract: In order to provide some background for subsequent sections in this review, the physical properties, aqueous equilibria, and kinetics of CO2 (aq) and its hydrolysis products are discussed briefly. The procedures for the preparation of metal carbonato complexes, their spectral characteristics, and their x-ray crystallographic structures are tabulated. Solid-state thermal reactions for producing certain carbonato complexes are discussed. The equilibrium section of the article serves mainly to list current values of stability constants, ion-pair formation constants and solubility data, and the related thermodynamic data for metal carbonato complexes. The section on kinetics of the metal carbonato complexes is composed of a detailed discussion of the individual modes of reaction with present-day concepts of the mechanisms involved in these processes and how the data for each type of reaction can be correlated. The material of the relatively new field involving metal-carbon dioxide complexes is divided into three sections. These section include discussion of preparation and characterization of the metal-CO2 species and CO2 fixation and insertion reactions. The review is concluded with applied sections on geochemistry, oceanography, and biochemistry, which are meant to give research chemists insight into some of the applied aspects and implications of carbonato metal chemistry in these areas.more » 628 references, 9 figures, 41 tables.« less

391 citations


Journal ArticleDOI
TL;DR: The leukotrienes are formed by transformation of arachidonic acid into an unstable epoxide intermediate, which can be converted enzymatically by hydration, and by addition of glutathione to leukiotriene C4 as mentioned in this paper.
Abstract: Arachidonic acid plays a central role in a biological control system where such oxygenated derivatives as prostaglandins, thromboxanes, and leukotrienes are mediators. The leukotrienes are formed by transformation of arachidonic acid into an unstable epoxide intermediate, leukotriene A4, which can be converted enzymatically by hydration to leukotriene B4, and by addition of glutathione to leukotriene C4. This last compound is metabolized to leukotrienes D4 and E4 by successive elimination of a gamma-glutamyl residue and glycine. Slow-reacting substance of anaphylaxis consists of leukotrienes C4, D4, and E4. The cysteinyl-containing leukotrienes are potent bronchoconstrictors, increase vascular permeability in postcapillary venules, and stimulate mucus secretion. Leukotriene B4 causes adhesion and chemotactic movement of leukocytes and stimulates aggregation, enzyme release, and generation of superoxide in neutrophils. Leukotrienes C4, D4, and E4, which are released from the lung tissue of asthmatic subjects exposed to specific allergens, seem to play a pathophysiological role in immediate hypersensitivity reactions. These leukotrienes, as well as leukotriene B4, have pro-inflammatory effects.

357 citations



Journal ArticleDOI
TL;DR: Aggregates of bacteriochlorophylls c, d, and e and of zinc(II) methyl bacteriopheophorbides c and d, which exhibit large red shifts in hexane without the essential intervention of any carbonyl function on ring V are described in this article.
Abstract: Aggregates of bacteriochlorophylls c, d, and e and of zinc(II) methyl bacteriopheophorbides c and d, which exhibit large red shifts in hexane without the essential intervention of any carbonyl function on ring V are described. The aggregates appear to provide viable in vitro models for the antenna chlorophylls of green and brown photosynthetic bacteria and a rationale for the presence of the 2-(1-hydroxyethyl) group in bacteriochlorophylls c, d, and e.

182 citations




Journal ArticleDOI
TL;DR: In this paper, the authors describe a mixture of N-Trimethylsilylimin (Ib) and allyl-grignard-Verbindungen.
Abstract: Aus dem Aldehyd (Ia) erhalt man mit Lithium-bis-trimethylsilylamid (IV) das N-Trimethylsilylimin (Ib), das mit Allylgrignard-Verbindungen umgesetzt und zum allylierten Amin (II) in hoher Ausbeute verseift wird.

151 citations



Book ChapterDOI

142 citations


Journal ArticleDOI

138 citations



Journal ArticleDOI
TL;DR: In this paper, the enediyls were converted into the first organosamarium hydride complex, a molecule that represents a new crystallographically characterized class of organolanthanide hydrides.
Abstract: The reaction of (C/sub 5/Me/sub 5/)/sub 2/Sm(THF)/sub 2/ with internal alkynes to form a new class of organolanthanide complexes, the enediyls, is reported. These can be converted into the first organosamarium hydride complex, a molecule that represents a new crystallographically characterized class of organolanthanide hydrides.

Journal ArticleDOI
TL;DR: In this paper, the authors discuss the assignment of NMR signals in the NMR spectra of mono-and oligosaccharides and their derivatives, and the use of these values in the study of carbohydrates.
Abstract: Publisher Summary This chapter deals with the use of nuclear magnetic resonance (NMR) spectroscopy in the study of mono– and oligosaccharides. The importance of NMR spectroscopy in the study of carbohydrates has increased tremendously. This has occurred primarily because the introduction of pulsed Fourier transform (FT) NMR spectrometers has made the measurement of I3 C NMR spectral parameters easy, which is particularly important for the study of carbohydrates in aqueous solutions. In addition, pulsed NMR instruments have increased the sensitivity of 'H NMR spectra by several orders of magnitude and facilitated the measurement of relaxation times and nuclear Overhauser enhancement (NOE) factors. The chapter discusses the way to assign NMR parameters and the way to use these values in the study of carbohydrates. Moreover, the chapter illustrates that the assignment of the NMR signals is a prerequisite for the application of NMR spectroscopy in structural investigations of carbohydrates. Because assignment techniques have been described in many reviews and monographs, special emphasis is given to the problems associated with the assignment of signals in the NMR spectra of carbohydrates and their derivatives.













Journal ArticleDOI
TL;DR: In this paper, the authors present a review of organic preparation and procedures and their application in the field of organic gardening, and discuss the following topics:Organic ThionitrITres and RELATED SUBSTANCES
Abstract: (1983) ORGANIC THIONITRITES AND RELATED SUBSTANCES A REVIEW Organic Preparations and Procedures International: Vol 15, No 3, pp 165-198