Fortschritte der Chemie organischer Naturstoffe / Progress in the Chemistry of Organic Natural Products

More than ten years have elapsed since the publication of a compre­ hensive review on the quassinoids, the bitter principles of the Simaroubaceae family (80). Interest in these terpenoids has increased enormously in recent years due in part to the finding of the American National Cancer Institute in the early 1970s that these compounds display marked antileukemic activity. Furthermore, a wide spectrum of other biological properties for the quassinoids has been discovered and studies on chemical modifications of inactive members to yield biologically active ones were undertaken. New structures have been established also and numerous synthetic approaches have been developed which include the total synthesis of the parent compound, quassin (p. 250) and also that of castelanolide (p. 253). It is intended that this present chapter will be an extension of my first review in this series and will contain references up to September 1984. A short article on some aspects of this subject was published recently (81). II. Quassinoid General Features In reviewing the essential features of the quassinoids, the new structural types discovered during the last decade will be emphasised. The quassinoids can be divided into distinct groups according to their basic skeletons. The five skeletons observed are presented on Chart 1.

Contenu

Naturally Occurring ?-Lactams.- I. Introduction.- II. Nocardicins.- III. Monobactams.- IV. Penicillins.- V. Clavulanic Acid.- VI. Olivanic Acids, Thienamycin and Other Carbapenems.- VII. Cephalosporins and Cephamycins.- VIII. Pachystermines, Wild-Fire Toxin and Antimetabolites.- IX. Biosynthesis.- 1. Biosynthesis of Nocardicin A.- 2. Biosynthesis of the Monobactams.- 3. Biosynthesis of the Penicillins.- 4. Biosynthesis of Clavulanic Acid.- 5. Biosynthesis of Carbapenem Antibiotics.- 6. Biosynthesis of the Cephalosporins.- References.- New Techniques for the Mass Spectrometry of Natural Products.- I. Introduction.- II. Methods of Ionization.- II.1. Electron Impact.- II.2. Chemical Ionization.- II.3. Desorption Chemical Ionization.- II.4. Field Desorption.- II.5. Secondary Ion Mass Spectrometry and Fast Atom Bombardment Mass Spectrometry.- II.6. Plasma Desorption Mass Spectrometry.- II.7. Laser Desorption Mass Spectrometry.- II.8. General Comments and Future Prospects.- III. Other Techniques in Mass Spectrometry.- III.1. High-Mass Spectra.- III.2. Tandem Mass Spectrometry.- III.3. Coupled Chromatography.- III.4. Computers.- III.5. Quantitative Measurements.- IV. Applications of the Newer Techniques in Mass Spectrometry to Specific Classes of Natural Product.- IV. 1. Peptides and Proteins.- IV. 2. Carbohydrates.- IV. 3. Nucleotides.- IV. 4. Tetrapyrroles.- IV. 5. Fatty Acids, Alcohols, and Esters.- IV. 6. Complex Lipids.- IV. 7. Eicosanoids.- IV. 8. Steroids.- IV. 9. Antibiotics.- IV. 10. Miscellaneous Natural Products.- References.- Chemical Synthesis of the Trichothecenes.- I. General Introduction.- II. Origin and Biological Activity.- III. Structure.- IV. Synthesis of the Simple Sesquiterpenoid Trichothecenes.- 1. Introduction.- 2. The Aldol Approach.- 3. The Biomimetic Approach.- 4. Miscellaneous Approaches.- V. Synthesis of the Trichoverroids.- 1. Introduction.- 2. Total Syntheses.- VI. Synthesis of the Macrocycles.- 1. Introduction.- 2. Model Systems.- 3. Verrucarin A.- 4. Verrucarin J.- 5. Verrucarin B.- 6. Roridin E and Baccharin B5.- 7. Vertisporin.- References.- Quassinoid Bitter Principles II.- I. Introduction.- II. Quassinoid General Features.- III. Structure Determination of Quassinoids.- 1. C18-Quassinoids.- 2. C19-Quassinoids.- 3. C20-Quassinoids.- 4. C25-Quassinoids.- IV. Physical Methods.- V. Biological Activity.- 1. Antileukemic Activity.- 2. Antiviral Activity.- 3. Antimalarial Activity.- 4. Antifeedant and Insecticidal Properties.- 5. Amebicidal Activity.- 6. Anti-inflammatory Activity.- VI. Chemical Modifications.- VII. Synthetic Studies.- VIII. Total Synthesis of dl-Quassin.- IX. Total Synthesis of dl-Castelanolide.- X. Tables 3-6.- References.- Author Index.