NMR analysis of 15N-labeled naphthyridine carbamate dimer (NCD) to contiguous CGG/CGG units in DNA

The structure of the complex formed by naphthyridine carbamate dimer (NCD) binding to CGG repeat sequences in DNA, associated with fragile X syndrome, has been elucidated using 15N-labeled NCD and 1H-15N HSQC. In a fully saturated state, two NCD molecules consistently bind to each CGG/CGG unit, maintaining a 1 : 2 binding stoichiometry.

Self-Assembled Multilayer Iron(0) Nanoparticle Catalyst for Ligand-Free Carbon-Carbon/Carbon-Nitrogen Bond-Forming Reactions

Self-assembled multilayer iron(0) nanoparticles (NPs, 6-10 nm), namely, sulfur-modified Au-supported Fe(0) [SAFe(0)], were developed for ligand-free one-pot carbon-carbon/carbon-nitrogen bond-forming reactions. SAFe(0) was successfully prepared using a well-established metal-nanoparticle catalyst preparative protocol by simultaneous in situ metal NP and nanospace organization (PSSO) with 1,4-bis(trimethylsilyl)-1,4-dihydropyrazine (Si-DHP) as a strong reducing agent. SAFe(0) was easy to handle in air and could be recycled with a low iron-leaching rate in reaction cycles.

Pyrolysis of Iron-Containing Polyanilines under Micropore Generation Control: Electrocatalytic Performance in the Oxygen Reduction Reaction

Pyrolyzed iron-containing polyaniline (C-Fe-PANI) is one of the most promising candidates as a non-precious metal based electrocatalyst for oxygen reduction reaction (ORR). Although the ORR activity depends on the surface area arisen from pyrolysis-generated micropores on C-Fe-PANI particles, the micropore generation is hindered by pyrolysis-formed iron nanoparticles (Fe NPs) embedded inside C-Fe-PANI particles. Here, we demonstrate the pyrolysis of iron-containing PANIs under suppression of micropore-generation hindrance by blocking the Fe NPs formation. The higher-molecular-weight (MW: 100,000) PANI was dispersed in an FeCl₃ solution before pyrolysis for preventing FeCl₃ penetration inside PANI particles. As a result, as compared to the case of lower-MW (5,000) PANI, the Fe NPs formation was more suppressed inside catalyst particles to give 1.9 (1.8) times micropore volume (specific surface area), leading to a 11 % higher current density in ORR electrocatalytic performance test in acidic media.