Novel tricyclic bridged heterocyclic systems can be readily prepared from sequential 1,4- and 1,2-addition reactions of allyl and 3-substituted allylsilanes to indolizidine and quinolizidine α,β-unsaturated N-acyliminium ions. These reactions involve a novel N-assisted, transannular 1,5-hydride shift. Such a mechanism was supported by examining the reaction of a dideuterated indolizidine, α,β-u...

The important biochemical probe molecule brefeldin A (1) has served as an inspirational target in the past, but none of the many routes has actually delivered more than just a few milligrams of product, where documented. The approach described herein is clearly more efficient; it hinges upon the first implementation of ruthenium-catalyzed trans-hydrogenation in natural products total synthesis....

Background: Repaired Tetralogy of Fallot (rTOF) patients may have residual lesions such as main (MPA) and branch pulmonary artery stenosis (BPAS). While MPA is well studied, few data are available on BPAS in rTOF. We aimed to describe perfusion a large paediatric cohort rTOF its impact right ventricular outflow-tract hemodynamics using 4D flow CMR. Methods: 130 consecutive (mean age at CMR 14.3...

The title acetone solvate, C(42)H(28)O(2)·C(3)H(6)O [systematic name: 1,3,10,12-tetra-phenyl-19,20-dioxapenta-cyclo-[10.6.2.0(2,11).0(4,9).0(13,18)]icosa-2(11),3,5,7,9,13,15,17-octa-ene acetone monosolvate], is a photooxygenation product of rubrene (systematic name: 5,6,11,12-tetra-phenyl-tetra-cene). The mol-ecule bends at the bridgehead atoms, which are linked by the O-O transannular bond, wi...

An enantioselective synthetic route to the enediyne antibiotic N1999A2 (1) is described, proceeding in 21 steps (0.4% yield, 77% average yield per step) from (R)-(+)-glycidol. The route involves the convergent assembly of three components: a (1-iodovinyl) stannane (2), a 1,5-hexadiyne-3,4-diol derivative (3), and a substituted naphthoic acid (4). Important transformations in the synthetic seque...