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The series of (1-terpenylindenyl) 2 ZrCl 2 bent metallocene complexes (with terpenyl substituents neomenthyl, neoisomenthyl, menthyl, and isomenthyl) were obtained from the reaction of the respective 1-terpenylindenyl lithium reagents with ZrCl 4 . In each case a single racem-like diastereoisomer was isolated pure by crystallization. The conformational analysis of the bent metallocene systems was carried out by variable temperature 1 H NMR spectroscopy. It has revealed the existence and equilibration of three different bent metallocene torsional isomers. Two of these are C 2 -symmetric and carry their bulky terpenyl substituents either in the lateral or the front sector of the bent metallocene wedge (descriptors bis-lateral:anti (conformer A) and bis-central:syn (conformer B)), whereas the rotational isomer C (central,lateral:gauche) is of lower symmetry. The (1-terpenylindenyl) 2 ZrCl 2 /methylalumoxane systems are active propene polymerization catalysts. The equilibrium amount of the "stereochemically productive" C 2 -symmetric bis-lateral:anti bent metallocene conformer A correlates qualitatively with the observed isotacticity of the propene polymerization process at the respective group 4 bent metallocene catalyst system.

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The unchanged pulmonary betaAR density in the presence of a previously described significant reduction in myocardial betaAR density in the same patient principally supports our pathophysiological hypothesis that the myocardial betaAR density may be reduced in ARVC and RVO-VT because of an increase in local synaptic catecholamine levels due to an organ-limited presynaptic adrenergic dysfunction of the heart. Since in the present study only pulmonary betaAR density was measured, future functional studies excluding pulmonary betaAR desensitisation are required to finally prove the unchanged pulmonary sympathetic innervation in ARVC and RVO-VT.