The regioselective alkylation of indoles with alcohols as alkylating reagents was developed by using Pd/C or RuCl2(PPh3)3/DPEphos {DPEphos = bis[(2‐diphenylphosphanyl)phenyl] ether}as catalysts. The reaction of indole with benzyl alcohol in the presence of Pd/C and K2CO3 at 80 °C for 24 h without any solvent under in air yielded 90 % of 3‐benzylindole. The corresponding 3‐benzylindole was obtained in 99 % yield when the reaction was catalyzed by RuCl2(PPh3)3/DPEphos in the presence of K3PO4 at 165 °C for 24 h under argon. Several types of alcohols were treated with indoles under these conditions to give the corresponding 3‐alkylated indoles in high yields (up to 99 %). This reaction may involve the catalyst‐mediated transformation of alcohols to aldehydes, nucleophilic addition of indole to the resulting aldehydes accompanied by dehydration, and then hydrogenation.

Enantioselective synthesis of β‐amino alcohols from 1,2‐diols by the use of [RuCl2(p‐cymene)]2/(S,R)‐JOSIPHOS catalysis was developed. Several 1,2‐diols were treated with secondary amines to afford the corresponding optically active β‐amino alcohols in up to 99 % yield with 77 % ee.

Although amyloid fibrils are associated with numerous pathologies, their conformational stability remains largely unclear. Herein, we probe the thermal stability of various amyloid fibrils. α‐Synuclein fibrils cold‐denatured to monomers at 0–20 °C and heat‐denatured at 60–110 °C. Meanwhile, the fibrils of β2‐microglobulin, Alzheimer’s Aβ1‐40/Aβ1‐42 peptides, and insulin exhibited only heat denaturation, although they showed a decrease in stability at low temperature. A comparison of structural parameters with positive enthalpy and heat capacity changes which showed opposite signs to protein folding suggested that the burial of charged residues in fibril cores contributed to the cold denaturation of α‐synuclein fibrils. We propose that although cold‐denaturation is common to both native proteins and misfolded fibrillar states, the main‐chain dominated amyloid structures may explain amyloid‐specific cold denaturation arising from the unfavorable burial of charged side‐chains in fibril cores.

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Colorimetric indicator gels were developed by incorporating anthocyanin (AC) obtained from red cabbage into poly (ethylene glycol) diacrylate (PEGDA)-based hydrogel containing lignocellulose nanofiber (LCNF). The PEGDA-based hydrogel was prepared by mixing all of the mentioned components at the specific composition, and the hydrogels were cured under UV light (245 nm) for 1 min. The pH-response, UV absorption, swelling ratio, and mechanical properties of PEGDA/LCNF were determined. It was further found that PEGDA and LCNF mount play an important role in adjusting the mechanical properties of PEGDA/LCNF. In general, the presence of LCNF improved the mechanical properties and swelling ratio of PEGDA. The incorporation of red cabbage anthocyanin into the PEGDA/LCNF film showed multicolor response when specific pH buffers were introduced. Based on the multicolor response of PEGDA/LCNF/CA, this gel film indicator can be developed as a food freshness indicator that focuses on the detection of ammonia and amine compound.