Directed evolution of hybrid enzymes: Evolving enantioselectivity of an achiral Rh-complex anchored to a protein

The concept of utilizing the methods of directed evolution for tuning the enantioselectivity of synthetic achiral metal-ligand centers anchored to proteins has been implemented experimentally for the first time.     

Ancisheynine, the first n,c-coupled naphthylisoquinoline alkaloid: total synthesis and stereochemical analysis

[reaction: see text] The first total synthesis of an N,C-coupled naphthylisoquinoline alkaloid-ancisheynine-was achieved by condensing a monocyclic diketone or the respective benzopyrylium salt with an aminonaphthalene. The presence of a rotationally hindered axis in ancisheynine was demonstrated by resolution of its two atropo-enantiomers by HPLC on a chiral phase with LC-CD coupling. The assignment of their axial configurations succeeded by quantum chemical CD calculations.     

New synthetic protocols for the preparation of unsymmetrical bisindoles

Novel unsymmetrical bisindoles were synthesized by a solvent-free C-C bond-formation reaction under mild conditions. Starting from aziridines or hydroxyl precursors, indoles have been used as C-nucleophiles to form new pharmacologically interesting bisindoles via an electrophilic aromatic substitution pathway in good to excellent yields. [reaction: see text]     

Über die optimale Beleuchtung einer geraden Straße

The following problem is due toL. Fejes Tóth: For a given sort of lamps letf(x) be the intensity of brightness in each point having distancex from the foot of the lamp. How must infinitely many lamps of this kind be arranged on a both-side infinite rectilinear road, such that the infimum of the intensities of brightness, extended over the whole street, is maximal, subject to the condition that the average number of lamps per kilometer is bounded by a fixed number (“Best distributions”)? The main result of this paper is: Iff is strictly convex, the equidistant distribution is best.