Oleksandr

Over 25 years ago, Eaton proposed that cubane could act as a benzene bioisostere. This hypothesis has now been confirmed with the synthesis and evaluation of cubane derivatives of five biologically important molecules: Two cubane analogues showed increased bioactivity compared to their benzene counterparts whereas two further analogues were of equal bioactivity.

[Communication]
Benjamin A. Chalmers, Hui Xing, Sevan Houston, Charlotte Clark, Sussan Ghassabian, Andy Kuo, Benjamin Cao, Andrea Reitsma, Cody-Ellen P. Murray, Jeanette E. Stok, Glen M. Boyle, Carly J. Pierce, Stuart W. Littler, David A. Winkler, Paul V. Bernhardt, Cielo Pasay, James J. De Voss, James McCarthy, Peter G. Parsons, Gimme H. Walter, Maree T. Smith, Helen M. Cooper, Susan K. Nilsson, John Tsanaktsidis, G. Paul Savage, Craig M. Williams
Angew. Chem. Int. Ed., February 05, 2016, DOI: 10.1002/anie.201510675. Read article

Covalent and supramolecular polymers are two distinct forms of soft matter, composed of long chains of covalently and noncovalently linked structural units, respectively. We report a hybrid system formed by simultaneous covalent and supramolecular polymerizations of monomers. The process yields cylindrical fibers of uniform diameter that contain covalent and supramolecular compartments, a morphology not observed when the two polymers are formed independently. The covalent polymer has a rigid aromatic imine backbone with helicoidal conformation, and its alkylated peptide side chains are structurally identical to the monomer molecules of supramolecular polymers. In the hybrid system, covalent chains grow to higher average molar mass relative to chains formed via the same polymerization in the absence of a supramolecular compartment. The supramolecular compartments can be reversibly removed and re-formed to reconstitute the hybrid structure, suggesting soft materials with novel delivery or repair functions. Authors: Zhilin Yu, Faifan Tantakitti, Tao Yu, Liam C. Palmer, George C. Schatz, Samuel I. Stupp

Two carbohydrate receptors (see scheme) were prepared directly from a pyrenyl tetraamine and an isophthaloyl derivative. With extended aromatic surfaces linked by polar spacers, they are well suited to binding all-equatorial monosaccharides, showing especially high affinities for β-linked N-acetylglucosamine (GlcNAc).

[Communication]
Pablo Rios, Tom S. Carter, Tiddo J. Mooibroek, Matthew P. Crump, Micke Lisbjerg, Michael Pittelkow, Nitin T. Supekar, Geert-Jan Boons, Anthony P. Davis
Angew. Chem. Int. Ed., January 28, 2016, DOI: 10.1002/anie.201510611. Read article

Nature Chemistry. doi:10.1038/nchem.2425

Authors: Qi-Qiang Wang, Sergio Gonell, Stefan H. A. M. Leenders, Maximilian Dürr, Ivana Ivanović-Burmazović & Joost N. H. Reek

Preorganization of catalysts and substrates can lead to significant rate enhancement—an effect often observed in enzyme catalysis. Now, a self-assembled nanosphere equipped with 24 guanidinium binding sites is demonstrated to strongly bind sulfonate-containing gold catalysts. Base-triggered co-encapsulation of carboxylate containing substrates leads to pronounced gating effects and dramatically enhanced reaction rates.