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The tetrabenzylated catechin 9 was prepared by benzylation of the commercially available pure (+)-catechin (3) and coupled with the commercially unavailable pentabenzylated (-)-gallocatechin 10, prepared in a one-step Mitsunobu-type cyclization of the triol 8 The highly stereoselective synthesis of benzylated prodelphinidins - catechin-(4 alpha -> 8)-gallocatechin (13), gallocatechin-(4 alpha -> 8)-gallocatechin (14), and gallocatechin-(4 alpha -> 8)-catechin (15) - is reported for the first time. The ESI(+)-CID mass spectra of the coupling products were found to feature regioselective retro-Diels-Alder (RDA) reactions and unusual sequential losses of pairs of C7H7 radicals (182 u) from the Na+ adduct ions

The cover picture shows two low-energy geometries of a new bis(diamido)-bridged basket resorcin[4]arene, which features two (1R,2R)-(+)-1,2-diphenylethylenediamine bridges in its structure. The first “drops” schematically show the geometry assumed by the molecule in chloroform solution, tentatively designated as the “folded wings” structure (bottom left); the top right structure represents the geometry adopted when the solvent is removed and is named the “open wings” structure. Stochastic dynamics simulations run at 300 K, which demonstrate the irreversible conversion of the latter structure into the former one, support the “folded wings” geometry as the most likely 3D structure of the basket resorcin[4]arene in chloroform. It can be shown by FT-ICR mass spectrometry that such a receptor can selectively accommodate the enantiomers of amino acid derivatives and amphetamine in its chiral cavity. Details are discussed in the article by B. Botta, M. Speranza et al. on p. 5995 ff. The authors thank Dr. Giovanna Cancelliere and Dr. Deborah Subissati for their contribution in designing the cover page.