Hydrophilic anchoring is introduced as a promising strategy to constructively control the various interactions of synthetic pore sensors with the surrounding biphasic environment. Artificial rigid-rod beta barrels are selected as classical synthetic multifunctional pores and random-coil tetralysines are attached as hydrophilic anchors. The synthesis of this advanced pore is accomplished in 32 steps from commercially available starting materials. With regard to pore activity as such, the key impact of hydrophilic anchoring is a change from a Hill coefficient n<1 to n=4. This change confirms successful suppression of the competing self-assembly with precipitation from the aqueous phase as the origin of the accomplished increase in pore activity. The hydrophilic anchors do not interfere with the blockage of the synthetic pore sensors by anionic analytes. In the case of stoichiometric binding of blockers (K(D)=EC(50) of the pore; EC(50)=concentration needed to observe 50 % pore activity), however, the increase in pore activity achieved by hydrophilic anchoring results in improved pore blockage under high dilution conditions. Controls confirm that this increase does not occur with analytes that do not exhibit stoichiometric binding (K(D)>EC(50)). These results not only reveal stoichiometric binding as the expected origin of the sensitivity limit of synthetic pore sensors, they also provide promising solutions for this problem. The combination of hydrophilic anchoring with targeted pore formation emerges as a particularly promising strategy to further reduce effective pore concentrations. The scope and limitations of this approach are exemplified with pertinent analyte pairs that are essential for the sensing of sucrose, lactose, acetate, and glutamate with synthetic pores in samples from the supermarket.

The creation of functional materials such as ion channels, porous sensors, or smart photosystems depends critically on our ability to assemble sophisticated, error-free and self-repairing nanoarchitecture in a predictable manner. To address these challenging topics, we often used lipid bilayer membranes as compartmentalizing platform and have introduced rigid-rod molecules as privileged scaffolds that bypass all folding problems because they do not fold. This approach provides access to motifs such as rigid-rod barrels, helices, stacks, slides, and wires that can act as smart, stimuli-responsive photosystems, pores, ion channels, hosts, sensors, and catalysts. The selected examples focus on naphthalenediimides (NDIs), a compact, organizable, colorizable, and functionalizable n-semiconductor. This versatile module is used in rigid-rod molecules to mediate transmembrane anion transport by anion-interactions, as sticky -clamp within pore sensors to catch otherwise elusive analytes by aromatic electron donor-acceptor interactions, or in blue, transmembrane -stack architecture to collect and convert photonic energy. These specific examples with multifunctional NDI nanoarchitecture are of help to outline, on the one hand, possibilities to contribute to advanced functional materials such as multianalyte sensors or solar cells and, on the other hand, to keep on wondering about an enormous structural and functional space waiting to be explored.In biology, highest sophistication on both the structural and functional level is accomplished with membrane proteins. Ion channels and pores, for instance, function as stimuli-responsive multianalyte sensors that assure perception of and communication with the outside world.

N-Phenylaminomethyl benzimidazolyl moieties attached at C-2 of (2S,3S,4R,5S)-5-methylpyrrolidine-3,4-diol increase the potency and selectivity of the inhibitory activity of these systems towards alpha-L-fucosidases.

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Pyrrole derivatives R 0120 Stereoselective Synthesis of (2S,3S,4R,5S)-5-Methylpyrrolidine-3,4-diol Derivatives that Are Highly Selective α-L-Fucosidase Inhibitors. -A new method for the synthesis of the title compounds bearing either aminomethyl or heterocyclic moieties, e.g. (VIII) and (XI) at C-2 is described. (VIII) is a selective and competitive inhibitor of α-L-fucosidase. -(MORENO-VARGAS, A. J.; CARMONA, A. T.; MORA, F.; VOGEL, P.; ROBINA*, I.; Chem.

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Abstract:The objective with synthetic multifunctional nanoarchitecture is to create large suprastructures with interesting functions. For this purpose, lipid bilayer membranes or conducting surfaces have been used as platforms and rigid-rod molecules as shape-persistent scaffolds. Examples for functions obtained by this approach include pores that can act as multicomponent sensors in complex matrices or rigid-rod π-stack architecture for artificial photosynthesis and photovoltaics.Keywords: nanoarchitecture; sensors; photovoltaics; photosynthesis; lipid bilayer; scaffolds.The objective with synthetic multifunctional nanoarchitecture is to create large suprastructures with interesting functions [1,2]. To address this challenge, we often begin with lipid bilayer membranes or, more recently, conducting surfaces as platforms. To direct, control, and stabilize advanced functional architecture, rigid-rod molecules [3][4][5][6][7][8][9][10] have been introduced as shape-persistent scaffolds. Somehow the antithesis to foldamers [11,12], these simple sturdy rods are attractive scaffolds, bypassing all folding problems because they do not fold. Unknown in biology, rigid-rod molecules are much appreciated in the materials sciences [3]. Prominent members of this family of oligomeric molecules include oligoacetylene 1, p-oligophenyls 2 [4,5] and their formal mixture, i.e., p-oligophenyleneethynylene (OPE) rods 3 [6,7] (Fig. 1). Whereas the benzene rings in p-oligophenyls 2 and OPEs 3 can rotate more or less freely, oligonaphthalenes 4 cannot. This produces an exceptionally complex axial stereochemistry [8]. Rigid oligonaphthalenediimide (O-NDI) rods 5 [9] and oligoperylenediimides (O-PDI) rods 6 [10] are of interest because they are colorizable, π-acidic n-semiconductors. Oligoporphyrins are extensively studied because of their optoelectric properties, the nonplanar rod 7 has been elongated up to l = 1060 Å of the monodisperse 128-mer [11].From this rich collection of rigid-rod molecules, we originally selected p-oligophenyls 2 as model rods [1,2,14]. p-Oligophenyls are not only straightforward to synthesize and derivatize but also nonplanar and fluorescent, and can exhibit a dynamic axial chirality. The torsion angles between neighboring phenyls of the p-oligophenyl scaffold provide the directionality that is needed to control advanced supramolecular architecture. Dynamic chirality and fluorescence are of use for structural studies in