A library of oligomeric compounds was synthesized based on the imidazole-4,5-dicarboxylic acid scaffold along with amino acid esters and chiral diamines derived from amino acids. The final compounds incorporate nonpolar amino acids (Leu, Phe, Trp), polar amino acids (Ser, Asp, Arg), and neutral amino acids (Gly, Ala), and were designed to be useful in screening for inhibitors of protein-protein...

Prions are lethal mammalian pathogens composed of aggregated conformational isomers of a host-encoded glycoprotein and which appear to lack nucleic acids. Their unique biology, allied with the public-health risks posed by prion zoonoses such as bovine spongiform encephalopathy, has focused much attention on the molecular basis of prion propagation and the "species barrier" that controls cross-s...

Recognition of different human telomeric G-quadruplex structures has been a very important task for developing anti-cancer drug design. However, it also is a very challenging question since multiple conformational isomers of telomeric G-quadruplexes coexist under some conditions. Here, three different conformations including parallel, antiparallel, and mixed-type telomeric G-quadruplex structur...

BACKGROUND Atomic level rotamer libraries for sidechains in proteins have been proposed by several groups. Conformations of side groups in coarse-grained models, on the other hand, have not yet been analyzed, although low resolution approaches are the only efficient way to explore global structural features. RESULTS A residue-specific backbone-dependent library for sidechain isomers, compatib...

Many molecules exhibit multiple rotational isomers (conformers) that interconvert thermally and are difficult to isolate. Consequently, a precise characterization of their role in chemical reactions has proven challenging. We have probed the reactivity of specific conformers by using an experimental technique based on their spatial separation in a molecular beam by electrostatic deflection. The...

A self-catenated Zn(II)-organic framework formulated as [Zn2(3,3'-bpeab)(oba)2]·DMF (1) exhibiting a six-connected 44·610·8 topology has been successfully synthesized through the mixed-ligand of kinked 3,3'-bis[2-(4-pyridyl)ethenyl]azobenzene (3,3'-bpeab) and 4,4'-oxybis-benzoic acid (H2oba) under solvothermal condition. UV light triggers isomerization of complex 1 in a single-crystal-to-single...

A new clip-like receptor, which comprises two thiourea-based binding groups and two naphthalene units, has been designed and synthesized as a fluorescent chemosensor for distinguishing o-phthalate from two other isomers of dicarboxylates. Upon the addition of these three ions, the emission intensity at 420 nm (excitation at 340 nm) decreases drastically through PET. When excited at 380 nm, a ne...

Under physiological conditions, the pentameric human plasma protein serum amyloid P component (SAP) binds hexanoyl bis(D-proline) (R-1-{6-[R-2-carboxy-pyrrolidin-1-yl]-6-oxo-hexanoyl}pyrrolidine-2-carboxylic acid; CPHPC) through its D-proline head groups in a calcium-dependent interaction. Cooperative effects in binding lead to a substantial enhancement of affinity. Five molecules of the bivale...