Calix[N]arenes with extended perfluorinated domains at the lower rim

Lower rim arylation of calix[n]arenes with extended perfluorinated domains

Abstract Exhaustive O-arylation of p-tert -butylcalix[ n ]arenes 2 ( n  = 4–8) with an excess of 3-pentadecafluoroheptyl-5-pentafluorophenyl-1,2,4-oxadiazole 3 and K 2 CO 3 in refluxing acetonitrile provides an easy entry to a new family of perfluorinated calix[ n ]arenes 1 . The cyclic tetramer furnishes a mixture of cone , partial cone , and 1,2-alternate conformers, while the larger macrocycles afford single products. The structures of all new compounds are substantiated by NMR techniques and MALDI-TOF mass spectral data. Single-crystal X-ray diffraction studies on the pentamer derivative 1b reveal a distorted cone-in conformation of the calixarene cup.

Multimodality imaging approach to paradoxical embolism: a cauliflower mass on the Eustachian valve

The Eustachian valve was first described by Bartolomeo Eustachio (Italian anatomist) at 1552. It is an embryological remnant of the inferior vena cava valve that prenatally directs the oxygenated blood from inferior vena cava across the patent foramen ovale (PFO) into systemic circulation. Generally, following birth, after the closure of the foramen ovale it gradually regresses and not have a specific function, but it may persist in some patients as a floating membrane in the right atrium (RA), a nonpathological functionless structure.1 The prevalence of Eustachian valve in the normal population is unknown. Generally, it is an incidental finding without any significant pathophysiological co…