Inner-Bond-Cleavage Approach to Figure-Eight Macrocycles from Planar Aromatic Hydrocarbons.

Figure-eight-shaped nonplanar π-systems adopt distinctive chiral -symmetric structures, which are ideal for realizing efficient circularly polarized luminescence (CPL). However, the short-step and enantioselective synthesis of figure-eight π-systems represents a considerable challenge for the conventional bottom-up synthetic strategy. Herein, we report that the oxidative cleavage of the internal double bond of a commercially available polycyclic aromatic hydrocarbon, i.

Synthesis of sterically congested double helicene by alkyne cycloisomerization.

Alkyne cycloisomerization of 2,7,10,15-tetra(-alkynylphenyl)benzo[,]chrysene containing bulky 4-alkoxy-2,6-dimethylphenyl groups at the alkyne terminals selectively proceeded at the sterically crowded bay-region. The obtained double helicene adopts a distorted structure with a high racemization barrier due to the intramolecular steric repulsion.

Effect of Internal Substituents on the Properties of Dibenzo[,]chrysene.

We investigated the chemical and physical properties of internally functionalized dibenzo[]chrysene (DBC) derivatives. These molecules exhibit chiral double-helicene-like structures that are configurationally stable at ambient temperatures. The internal substituents control the conformational change in the excited state, thereby modulating the emission intensity.

Purification and characterization of thermostable H2O2-forming NADH oxidase from 2-phenylethanol-assimilating Brevibacterium sp. KU1309.

A cytoplasmic NADH oxidase (NOX) was purified from a soil bacteria, Brevibacterium sp. KU1309, which is able to grow in the medium containing 2-phenylethanol as the sole source of carbon under an aerobic condition. The enzyme catalyzed the oxidation of NADH to NAD+ involving two-electron reduction of O2 to H2O2.

Purification and characterization of aldehyde dehydrogenase with a broad substrate specificity originated from 2-phenylethanol-assimilating Brevibacterium sp. KU1309.

Phenylacetaldehyde dehydrogenase (PADH) was purified and characterized from Brevibacterium sp. KU1309, which can grow on the medium containing 2-phenylethanol as the sole carbon source. This enzyme was a homotetrameric protein with a subunit of 61 kDa.

Purification and characterization of the alcohol dehydrogenase with a broad substrate specificity originated from 2-phenylethanol-assimilating Brevibacterium sp. KU 1309.

A novel 2-phenylethanol dehydrogenase has been purified from a soil bacterium Brevibacterium sp. KU 1309. The enzyme was purified about 1400-fold to homogeneity, and found to be a monomeric enzyme of apparent 39 kDa.

Efficient oxidation of alcohols by a 2-phenylethanol-degrading Brevibacterium sp.

Microorganisms which can assimilate 2-phenylethanol were screened from soil for oxidation of various alcohols into carbonyl compounds. One strain, identified as Brevibacterium sp. KU1309, had high oxidative activity towards ArCH(CH(3))CH(2)OH and Ar(CH(2))(n)OH.