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Lychnopholide is a sesquiterpene lactone usually obtained from Lychnophora and Eremanthus species and has pharmacological activities that include anti-inflammatory and anti-tumor. Lychnopholide isolated from Eremanthus matogrossenssis was analyzed in this study. The aims of this study were to develop and validate an analytical methodology by LC-MS/MS and to quantify lychnopholide in rat plasma. Chromatographic separation was achieved on a C18 column using isocratic elution with the mobile phase consisting of methanol and water (containing 0.1% formic acid) at a flow rate of 0.4 mL/min. The detection was performed in multiple-reaction monitoring mode using electrospray ionization in positive mode. The method validation was performed in accordance with regulatory guidelines and the results met the acceptance criteria. The linear range of detection was 10-200 ng/mL (r > 0.9961). The intra- and inter-day assay variability were

l-Methyl-cis, cis-cyclooctadiene-1,5 was obtained by mixed butadiene-isoprene dimerization in the presence of a catalyst prepared by treating nickel acetylacetonate with lithium boron hydride in the presence of triphenyl phosphite. In analogy with cis, cis-cyclooctadiene-1,5, methyleyclooctadiene can be polymerized, in the presence of the Al(iC4H9)3 + TiCl4 eatalytic system (molar ratio of Al to Ti = 0.5), to an essentially saturated product. Also in this case a transannular polymerization of the following type occurs: In the terpolymerization with ethylene and propylene, on the contrary, methyl cyclo-octadiene reacts, in the presence of catalysts prepared from vanadium and alkyl aluminum compounds, by opening of the nonsubstituted double bond. The IR spectra of the monomer and of the polymers are here described.

Two hypothesis are proposed on the formation of vinyl double bonds in polypropylenes obtained in anionic coordination polymerization at temperatures above 100°C. According to the first hypothesis, the vinyl double bonds originate from a termination mechanism during which one of the hydrogen atoms in the methyl group of propylene combines with the growing macromolecule, while the remaining allyl group combines with the catalytic complex. The metal-allyl bond could thus bring about a new macromolecule containing a vinyl double bond as terminal group. Some experimental evidence supporting this hypothesis are examined. Afterwards, an other hypothesis, based on the results obtained by K. ZIEGLER and coworker on pyrolyzing some isoalkylaluminum compounds has been discussed. Es werden zwei Hypothesen aufgestellt zur Bildung von Vinyldoppelbindungen in Polypropylenen, die durch anionisch-koordinative Polymerisation bei Temperaturen oberhalb von 80°C erhalten werden. Gemas der ersten Hypothese entstehen diese Vinyldoppelbindungen infolge eines Abbruchsprozesses, bei dem eines der Wasserstoffatome der Methylgruppe des Propylens an das wachsende Makromolekul angelagert wird, wahrend sich die verbleibende Allylgruppe mit dem Katalysatorkomplex vereinigt. Die entstandene Metall-Allylbindung konnte dann ein neues Makromolekul starten, das als Endgruppe eine Vinyldoppelbindung tragen wurde. Einige experimentelle Ergebnisse, die die Gultigkeit dieser Hypothese bestatigen, werden mitgeteilt. Anschliesend wird eine weitere Hypothese diskutiert, die auf den von K. ZIEGLER und Mitarb. bei der Pyrolyse einiger Isoalkyl-aluminium-Verbindungen erhaltenen Ergebnisse beruht.

Although aberrant locations are typical complications of central venous catheterization, the right internal thoracic vein (mammary vein) is an exceptional one. A case of this unusual aberrant location occurring after right internal jugular venous cannulation for total parenteral nutrition, is described. This aberrant position caused signs and symptoms resembling pulmonary embolism. This is the first known description of the symptoms induced by the infusion of parenteral solution into the right internal thoracic vein.