Chemical communication in frogs and wasps: Identification and synthesis of macrolides and terpenes

Die vorliegende Dissertation beschäftigt sich mit der Analyse von Femoraldrüsenextrakten verschiedener Madagaskarfrösche und Stromschnellenfrösche, sowie der Synthese eines Pheromons einer parasitären Wespe. Im Mantellid Frosch Gephyromantis pseudoasper konnte ein neuartiges Makrolid, Gephyromantolid B, durch eine NMR-Analyse identifiziert werden. Es wurde ebenfalls in einem Drüsensekret des Afrikanischen Riedfrosches Hyperolius viridiflavus gefunden. In Gephyromantis luteus konnte ein neuartiges, 10-gliedriges Makrolid mit drei stereogenen Zentren und einem erstmals bei Froschmakroliden auftauchendem Ethylsubstituenten identifiziert werden. Eine kurze stereoselektive Synthese ermöglichte einen Zugang zu verschiedenen Stereoisomeren, sodass die absolute Konfiguration als (4R,8S,9S)-4,8-Dimethylundecan-9-olid bestimmt wurde. In Gephyromantis tahotra wurde eine neuartige Verbindung terpenoiden Ursprungs entdeckt, dessen Struktur aufgrund mangelnder Substanzmenge nicht vollständig aufgeklärt werden konnte. Es gelang des Weiteren eine postulierte Makrolid Struktur aus Gephyromantis redimitus (Z)-5,6,9-Trimethylundec-4-en-10-olid in einer stereoselektiven Synthese in einem Diastereomerengemisch von (4E,6R,9S,10R)-5,6,9-Trimethylundec-4-en-10-olid und (4E,6R,9R,10S)-5,6,9-Trimethylundec-4-en-10-olid herzustellen. Die Analyse weiterer Femoraldrüsenextrakte verschiedener Mantellid Frösche zeigte viele noch nicht identifizierte Verbindungen, dessen Strukturaufklärung notwendig ist, um eine vollständige Charakterisierung der Sekrete zu erhalten. Die Femoraldrüseninhalte der Stromschnellenfrösche Odontobatrachus zeigte eine unbekannte Verbindung, dessen Struktur durch eine NMR-Analyse identifiziert wurde. Bei der neuen Verbindung Odontobrachadien handelt es sich um ein terpenoiden Grundkörper aus zwei fünf- und zwei sechsringen. Es scheint, dass die unbekannte Verbindung aus G. tahotra ein Diastereomer von Odontobrachadien ist. Es konnte die absolute Konfiguration des männlichen Sexualpheromons der parasitären Wespe Urolepis rufipes bestimmt werden. Das natürliche, enantioselektiv hergestellte Diol (2S,6S)-2,6-Dimethyl-7-octen-1,6-diol zeigte in biologischen Tests, dass neben dem hergestellten Diol (2R,6S)-2,6-Dimethyl-7-octen-1,6-diol nur das natürliche Stereoisomer attraktiv für weibliche Wespen ist. Die Verbindung wurde in einer Synthese mit einem Pseudoephedrin-Auxiliar über 8 lineare Stufen mit einer Gesamtausbeute von 15% stereoselektiv synthetisiert werden.The following thesis comprises the analysis of femoral glands of the Mantellid and Odontobatrachus frogs, as well as the synthesis of a sexual pheromone of the parasitoid wasp Urolepis rufipes. In the femoral gland extract of Gephyromantis pseudoasper was a novel macrolide identified by NMR, which is also a content in the gland of the African reed frog Hyperolius viridiflavus. A ten membered macrolide with three stereogenic centers and an ethyl side chain was identified in the femoral gland extract of Gephyromantis luteus. The novel macrolide Luteolid was synthesized in a stereoselective synthesis and the absolute configuration was established as (4R,8S,9S)-4,8-Dimethylundecane-9-olide. The femoral gland extract of Gephyromantis tahotra comprised an unknown terpenoid compound. Only a fragment of the structure could be identified by NMR because of lack of natural material. A proposed macrolide structure of Gephyromantis redimitus was synthesized in a stereoselective synthesis as two inseparable diastereomers of (4E,6R,9S,10R)-5,6,9-Trimethylundec-4-ene-10-olide und (4E,6R,9R,10S)-5,6,9-Trimethylundec-4-ene-10-olide. The analysis of further femoral gland extracts of different mantellid frogs showed many unknown compounds, which identification is needed to characterize the gland extracts. The femoral gland extract of Odontobatrachus showed one major compound. Its structure was identified by NMR and consists of four fused rings with two five and two six membered rings. It seems that the terpeneoid compound Odontobrachadien is a diastereomer of the unknown compound of G. tahotra. The absolute configuration of the male parasitoid wasp Urolepis rufipes was established. The diol (2S,6S)-2,6-dimethyl-7-octene-1,6-diol was enantioselective synthesized and showed in biological tests with female wasps to be the only active stereoisomer. The compound was synthesized with a pseudoephedrine auxiliary over 8 linear steps in 15% overall yield. The established synthetic route of Luteolid could be applied

Case Report : Supernormal Vascular Aging in Leningrad Siege Survivors

Age-related changes in the vascular system play an important role in the biological age and lifespan of a person and maybe affected from an early age onward. One of the indicators of changes in the vascular system is arterial wall stiffness and its main measure, i.e., carotid-femoral pulse wave velocity (cfPWV). We examined arterial wall stiffness in a sample of 305 Leningrad Siege survivors to assess how hunger and stressful conditions during fetal development and early childhood affected the state of the cardiovascular system at a later age and what factors may neutralize the negative impact sustained in early childhood. Here, we presented an evaluation of two unique patients with supernormal vascular aging (SUPERNOVA) phenotype from this cohort and described the details of congruence between hereditary resistance and practiced lifestyle yielding slower biological aging rate.Peer reviewe

RUB: brutal schön?

RUB: brutal schön? Ein Ausstellungsbuch Die Ruhr-Universität Bochum ist auch ein Stück Architekturgeschichte. Darauf machen hier Bochumer Studierende der Kunstwissenschaft aufmerksam, insbesondere auf die stilgeschichtliche Frage des Brutalismus. Neu in den Blick kommen dabei beispielsweise der Außenraum der Universität, aber auch Erfahrungen von Zeitzeugen aus der Gründungszeit. Die Publikation basiert auf einer Ausstellung im Herbst 2019, die als studentisches Projekt entstand. Hg. von Cornelia Jöchner, mit Grußworten von Axel Schölmerich, Erdmute Lapp, Constantin Goschle

Application of the European Charter on Local Self-Government in the Republic of Croatia

Europsku povelju o lokalnoj samoupravi donijelo je Vijeće Europe 1985. g. Povelja predstavlja multilateralni pravni instrument koji ima za cilj pružiti zaštitu načelu lokalne samouprave te ujedno predstavlja osnovu demokracije. Sadrži načela koja garantiraju političku, financijsku i administrativnu neovisnost lokalnih vlasti. Povelja definira zajedničke upravne standarde koji predstavljaju podlogu za uspješno funkcioniranje institucija Unije i država članica, pa predstavlja važan doprinos zaštiti zajedničkih europskih vrijednosti. Republika Hrvatska Povelju je ratificirala 1997. g., a postala je obvezujuća 1998. g. Tada je Republika Hrvatska prihvatila samo inicijalne odredbe, tj. obvezni minimum odredbi. No, 2008. g. Republika Hrvatska ratificirala je i ostale odredbe Povelje. Kako bi se uspješno implementirale odredbe Povelje u nacionalnom zakonodavstvu, formiran je zakonodavni i institucionalni okvir koji omogućuje primjenu novog koncepta lokalne samouprav

Application of the European Charter on Local Self-Government in the Republic of Croatia

Europsku povelju o lokalnoj samoupravi donijelo je Vijeće Europe 1985. g. Povelja predstavlja multilateralni pravni instrument koji ima za cilj pružiti zaštitu načelu lokalne samouprave te ujedno predstavlja osnovu demokracije. Sadrži načela koja garantiraju političku, financijsku i administrativnu neovisnost lokalnih vlasti. Povelja definira zajedničke upravne standarde koji predstavljaju podlogu za uspješno funkcioniranje institucija Unije i država članica, pa predstavlja važan doprinos zaštiti zajedničkih europskih vrijednosti. Republika Hrvatska Povelju je ratificirala 1997. g., a postala je obvezujuća 1998. g. Tada je Republika Hrvatska prihvatila samo inicijalne odredbe, tj. obvezni minimum odredbi. No, 2008. g. Republika Hrvatska ratificirala je i ostale odredbe Povelje. Kako bi se uspješno implementirale odredbe Povelje u nacionalnom zakonodavstvu, formiran je zakonodavni i institucionalni okvir koji omogućuje primjenu novog koncepta lokalne samouprav

Enantioselective synthesis and determination of the absolute configuration of the male sex pheromone of the parasitoid wasp Urolepis rufipes

Males of the parasitoid wasp Urolepis rufipes use 2,6-dimethyl-7-octene-1,6-diol as a sex pheromone to attract virgin females. Herein, we determine the absolute configuration of the pheromone to be (2S,6S)-2,6-dimethyl-7-octene-1,6-diol (2S,6S-6) and present a stereoselective synthesis of the natural enantiomer of this new linalool derivative. In addition, we show that female wasps respond to the natural 2S,6S-6 stereoisomer while 2R,6S-6 is behaviorally inactive

Fast and User-Friendly Detection of Flatfish Species (Pleuronectes platessa and Solea solea) via Loop-Mediated Isothermal Amplification (LAMP)

The detection of a Cytochrome b gene (cytb) for species differentiation in fish is intensively used. A fast alternative to expensive and time-consuming DNA barcoding is loop-mediated isothermal amplification (LAMP) in combination with efficient readout systems. For this reason, we developed LAMP assays for rapid species detection of Pleuronectes platessa and Solea solea, two economically important flatfish species in Europe that are prone to mislabeling. Species-specific primer sets targeting cytb were designed, and LAMP assays were optimized. With the optimized LAMP assays, we were able to detect up to 0.1 and 0.01 ng of target DNA of P. platessa and S. solea, respectively, and in each case up to 1% (w/w) of target species in mixtures with nontarget species. For future on-site detection, a lateral flow assay and a pocket-sized lab-on-phone assay were used as readout systems. The lab-on-phone assay with the S. solea specific primer set revealed cross-reactivity to Solea senegalensis. The assay targeting P. platessa proved to be highly specific. Both assays could be performed within 45 min and provided rapid and easy detection of fish species

Mass Spectrometry of Aliphatic Macrolides, Important Semiochemicals or Pheromones

Macrolides are a relatively common structural motif prevalent in Nature. However, the structures of these large ring lactones have been relatively difficult to elucidate via NMR spectroscopy due to the minute amounts of compounds that are sometimes obtainable from natural sources. Thus, GC-MS analysis of individual macrolactones has become the method of choice for the structural identification of these compounds. Here we discuss the mass spectrometric behavior of aliphatic macrolides, evaluating spectra from numerous compounds of various ring size, including derivatives containing methyl branches as well as double bonds. The specific fragmentation of these macrolactones under electron impact conditions allows for the development of a general rule set aimed at the identification of similar compounds by mass spectrometry. In addition, the mass spectra of dimethyl disulfide adducts of unsaturated macrolides are discussed. The mass spectra of almost 50 macrolides are presented