Naturwirkstoffe aus Pflanzen. Biodiversitätsforschung

Due to its deepened natural material research the transdisciplinary biodiversity research offers new options to therapeutical challanges of the 21st century. Besides phytochemicals, known for centuries, these natural materials also include recently known material such as antiviral active high polymer polyphenols of Mediterranean rockroses or new kinds of antiadipos active bitter‐tasting compounds. Natural ressources are invaluable. To protect and preserve these, detailed knowledge of biodiversity on Earth and its embedding in the biogeosystem is required.     

Darstellung von Polymeren aus dem Samenöl von Crambe Abyssinica. 4. Mitt. Polyamide aus Tridecancarbonsäure

Ohne Zusammenfassung     

Zur Kenntnis halogenierter Acetylene, 4. Mitt.: Monofluoracetylen aus Monofluoracetylentetrabromid

Zusammenfassung Monofluoracetylen läßt sich durch erschöpfende Bromabspaltung aus Monofluoracetylentetrabromid herstellen und durch Ausfrieren von mitgebildetem Acetylen befreien. Ausb. 70%. Reines Monofluoracetylen siedet 21° tiefer als Acetylen.1.–3. Mitt.: Ann. Chem.640, 1–15 (1961).     

Furancarbonsäuren aus Rinderharn

Furancarboxylic Acids in Cattle Urine The urine of cattle contains large amounts of furancarboxylic acids. The same acids were isolated from rats after feeding with methyl esters of the so-called F-acids. Since the F-acids were not detected in cattle-food, they must be produced somewhere in the body of cattle.     

3-Hydroxy-4-nitro-cyclohexanone aus Ketonen und 4-Nitrobuttersäurechlorid. Eine ringerweiternde Fünfringanellierung

3-Hydroxy-4-nitro-cyclohexanones from Ketones and 4-Nitrobutanoyl Chloride. A Ring Enlarging Five-Ring Annulation The 6-nitro-1, 3-diketones 5, 8, 9, 10 , and 11 , prepared by a 1:1 acylation at the C-atom of non-hindered lithium enolates with 4-nitrobutanoyl chloride according to equation 3, are cyclized with sodium hydrogen carbonate in aqueous tetrahydrofuran to give the hydroxy-nitro-ketones 13–17 . Such cyclic nitroaldols are not formed from the cyclopentanone, -heptanone, and -octanone, nor from the aryl derivatives 4, 6, 7 and 12 , respectively. Except for the vicinally trisubstituted compound 14 , the cyclization products are isolated in diastereomerically pure form. A crystal structure X-ray analysis reveals the trans-decalone and the cisβ-nitroalcohol configurations of the product 13 from cyclohexanone (see Fig. 1–3). Acetalization to 21–25 and catalytic hydrogenation of the nitro groups furnishes the amino alcohols 27–31 (Table 4) which are substrates for the Tiffeneau-Demjanow rearrangement (see Schemes 2, 3, 4 and 5), From the stereoelectronic control of this sextett rearrangement we deduce the configurations of the 1, 4-diketones 35, 36, 39, 40, 43, 44, 46 , and 47 formed under kinetic or thermodynamic conditions. The six-ring annulation with nitrobutanoic acid and the subsequent rearrangement are shown in Scheme 6; the sequence of reactions described here allows to carry out a ring enlargement of a cyclic ketone by one C-atom, with simultaneous annulation of a cyclopentanone ring.