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1 Cysteinyl-leukotrienes cause contractions and/or relaxations of human isolated pulmonary vascular preparations. Although, the localization and nature of the receptors through which these effects are mediated have not been fully characterized, some effects are indirect and not mediated via the welldescribed LT1 receptor. 2 In human pulmonary veins (HPV) with an intact endothelium, leukotriene D4 (LTD4) induced contraction above basal tone. This response was observed at lower concentrations of LTD4 in the presence of nitric oxide synthase inhibitor N4-nitro-L-arginine (L-NOARG). Contractions (in the absence and presence of L-NOARG) were partially blocked by the LT, antagonists (MK 571 and ICI 198615). 3 LTD4 relaxed HPV previously contracted with noradrenaline. This relaxation was potentiated by LT1 antagonists, but was abolished by removal of the endothelium. LTD4 also relaxed human pulmonary arteries (HPA) precontracted with noradrenaline but this effect was not modified by LT, antagonists. 4 The results suggest that contraction of endothelium-intact HPV by LTD4 is partially mediated via LT, receptors. Further, in endothelium-intact HPV, this contraction was opposed by a relaxation induced by LTD4, dependent on the release of nitric oxide, which was mediated, at least in part, via a non-LT, receptor. In addition, LTD4 relaxation on contracted HPA was not mediated by LT, receptors. 5 The mechanical effects of LTD4 on human pulmonary vasculature are complex and involve both direct and indirect mechanisms mediated via at least two types of cysteinyl-leukotriene receptors.

Bei Einwirkung der Olefine (II) auf den o‐Allyl‐Fe‐Komplex (I) entstehen die Cyclopentylderivate (III), während die Reaktion von (I) mit dem Acetylen (IV) mit 54% Gesamtausb.

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Ferrocenylvinyl cations bearing triarylmethyl, ferrocenylmethyl, ferrocenylcarbonyl, or cycloheptafrienyl groups attached to the vinylic p-carbon atom, and the phenylvinyl cation formed by protonation of 3-ferrocenyl-1 -phenylpropyne undergo intra-ionic cyclisation to give a variety of novel mono-, bi-, and tri-cyclic derivatives.

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