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.

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.- References.- New Techniques for the Mass Spectrometry of Natural Products.- I. Introduction.- II. Methods of Ionization.- III. Other Techniques in Mass Spectrometry.- IV. Applications of the Newer Techniques in Mass Spectrometry to Specific Classes of Natural Product.- References.- Chemical Synthesis of the Trichothecenes.- I. General Introduction.- II. Origin and Biological Activity.- III. Structure.- IV. Synthesis of the Simple Sesquiterpenoid Trichothecenes.- V. Synthesis of the Trichoverroids.- VI. Synthesis of the Macrocycles.- References.- Quassinoid Bitter Principles II.- I. Introduction.- II. Quassinoid General Features.- III. Structure Determination of Quassinoids.- IV. Physical Methods.- V. Biological 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.