Dem IPB wird erneut ein beispielhaftes Handeln im Sinne einer chancengleichheitsorientierten Personal- und Organisationspolitik bescheinigt. Das Institut erhält zum 6. Mal in Folge das TOTAL E-QUALITY…
Die Plant Science Student Conference (PSSC) wird seit 20 Jahren im jährlichen Wechsel von Studierenden der beiden Leibniz-Institute IPK und IPB organisiert. Im Interview erläutern Christina Wäsch…
Hock, K. J.; Knorrscheidt, A.; Hommelsheim, R.; Ho, J.; Weissenborn, M. J.; Koenigs, R. M.;Tryptamine Synthesis by Iron Porphyrin Catalyzed C−H Functionalization of Indoles with DiazoacetonitrileSynform2019/7A106-A108(2019)DOI: 10.1055/s-0037-1612176
Rene Koenigs developed a tryptamine synthesis by C–H functionalization of indoles with diazoacetonitrile.Tryptamines are important endogenous signaling molecules that play a pivotal role in biochemical processes like the regulation of the sleep–wake rhythm. The closely related serotonin possesses key regulatory functions in the cardiovascular system and organ development and plays a central role as a neurotransmitter in the central nervous system. The synthesis of tryptamines is typically conducted following a classic route starting with a Mannich reaction of an indole heterocycle, followed by quaternization of the amine, nucleophilic substitution with highly toxic cyanide and final reduction. Professor Rene Koenigs (RWTH Aachen University, Germany) and co-workers previously reported on carbene transfer reactions of the underexplored and explosive diazoacetonitrile reagent. In a team effort with the groups of Junior Professor Martin J. Weissenborn (Leibniz Institute of Plant Biochemistry and Martin-Luther University Halle-Wittenberg, Germany) and Dr. Junming Ho (University of New South Wales, Sydney) iron porphyrin catalyzed reactions of diazoacetonitrile with N‐heterocycles were developed to synthesize important precursors of tryptamines.
Publikation
Greff, A.; Porzel, A.; Schmidt, J.; Palfner, G.; Arnold, N.;Pigment pattern of the Chilean mushroom Dermocybe nahuelbutensis Garrido & E. HorakRec. Nat. Prod.11547-551(2017)DOI: 10.25135/rnp.69.17.01.027
Fruiting bodies of the Chilean mushroom Dermocybe nahuelbutenis Garrido & E. Horak (syn.: Cortinariusnahuelbutensis (Garrido & E. Horak) E. Valenz. & G. Moreno) were chemically investigated for the first time andafforded the new dimeric anthraqinone 7,7'-emodinphyscion (1) beside the know anthraquinones dermolutein (2),endocrocin (3), skyrin (4) and the dimeric pre-anthraquinone derivative flavomannin C (5). The chemotaxonomicsignificance of the pigments is discussed.
Publikation
Alresly, Z.; Lindequist, U.; Lalk, M.; Porzel, A.; Arnold, N.; Wessjohann, L. A.;Bioactive Triterpenes from the Fungus Piptoporus betulinusRec. Nat. Prod.10103-108(2016)
Phytochemical investigation of the ethyl acetate extract of the fruiting bodies from the basidiomycete Piptoporus betulinus led to the isolation of a new bioactive lanostane triterpene identified as 3 b -acetoxy-16-hydroxy-24-oxo-5α-lanosta-8- ene-21-oic acid (1). In addition, ten known triterpenes, polyporenic acid A (5), polyporenic acid C (4), three derivatives of polyporenic acid A (8, 10, 11), betulinic acid (3), betulin (2), ergosterol peroxide (6), 9,11-dehydroergosterol peroxide (7), and fomefficinic acid (9), were also isolated from the fungus. All isolated compounds were tested for antimicrobial activity against some Gram-positive and Gram-negative bacteria as well as against a fungal strain. The new triterpene and some of the other compounds showed antimicrobial activity against Gram-positive bacteria.
Publikation
Ali, N. A. A.; Wurster, M.; Arnold, N.; Lindequist, U.; Wessjohann, L.;Essential Oil Composition from Oleogum Resin of Soqotraen Commiphora kuaRec. Nat. Prod.270-75(2008)
The major constituents of the essential oil obtained by hydrodistillation from the oleogum resin of Commiphora kua Vollesen were identified by GC-MS. Sixteen constituents were detected from the essential oil, which constituted about (90.5%) of the total amount. Major constituents of the oil were α- cadinol (33.0%), g -cadinene (22.5%), d -cadinene (17.0%), isocaryophyllene (3.7%), allo-aromadendrene (2.8%), α-muurolene (2.7%), and α-humulene (2.4%). The Oil of Commiphora kua showed moderate antifungal activity against Cladosporium cucumerinum.