Pre-existing RBBB and elevated LCC calcification were identified as independent predictors for PPI. These two risk factors enabled us to distinguish between patients according to their risk for PPI after TAVI. Ex vivo simulations suggested an off-centreline shift of the balloon as a possible explanation.

From 4-0-unsubstituted glucose derivatives 1 a, b the 4-hydroxymethyl-substituted glucose derivatives 9 a, b were obtained via oxidation to the ketone, Wittig reaction with methylenetriphenylphosphorane, borane addition, and subsequent oxidation to yield the diastereomeric galactose-derived compounds 5a. b; the required inversion of configuration at C-4 was accomplished through oxidation to the formyl derivatives, base-catalyzed isomerisation, and then reduction. Transformation of hydroxymethyl derivatives 9a, b into the iodo derivatives l l a, b and reaction with n-butyllithium generated the C-lithiated species l l a A , bA which furnished with 0-benzyl-protected gluconolactone 12 the ketose derivatives 13a, b. Treatment with EtzO -BF, afforded under concomitant 6-0-debenzylation the spiroketals 15a. b. Hydrogenolytic 0-debenzylation and subsequent 0-acetylation led to compounds 16a and 16b, respectively. The anomeric ketoside configuration was derived from NOE experiments.In our recent endeavours to synthesize methylene-bridged C-disaccharides two approaches, namely a C6-nucleophile + C7-electrophile and a C6-electrophile + C7-nucleophile route, respectively, have been employed[' -' I (Scheme 1). For the latter approach a rigid 'Cq conformer, as shown in the 1,6-anhydro derivative of type A, was selected as the C7-nucleophile because the 4C1-derived conformer of type B exhibited undesired interactions between the 6-oxygen of the B moiety and the newly formed anomeric ketose center of the gluconolactone moiety, utilized as C6-electrophile[2,'1; thus, intramolecular ketoside formation was observed as the only reaction. We would like to report on this finding which has not only bearing on new methods for intramolecular glycoside bond f~r m a t i o n [~,~] but also for the design of macrolide syntheses and other related natural p r o d~c t s [~,~] .

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