The thermal [3,3] rearrangement of 3,3-dicyano-1,5-enynes to γ-allenyl alkylidenemalononitriles (the "enyne Cope rearrangement") has largely eluded synthetic value as the desired products, too, are thermally reactive and ultimately yield 6π electrocyclization products. Herein, we describe experimental and computational studies related to the thermal rearrangement of 1,5-enynes, structural features to halt the thermal rearrangement at the allene stage, and a reductive variant for preparing bifunctional allenyl malononitriles. We also describe various ways that the bifunctional building blocks can be manipulated and converted to cyclic and acyclic architectures.
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http://dx.doi.org/10.1021/jacs.8b08553 | DOI Listing |
Soft Matter
January 2025
The Institute of Mathematical Sciences, C.I.T. Campus, Taramani, Chennai 600113, India.
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January 2025
School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China. Electronic address:
Soy glycinin amyloid fibrils (11Fs) with different lengths were prepare, and their influence on 3D printing performance of high internal phase emulsions (HIPEs) were investigated. The longest fibril with an average length of 1594.40 ± 135.
View Article and Find Full Text PDFMater Horiz
January 2025
State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, School of Electrical and Electronic Engineering, North China Electric Power University, Beijing 102206, People's Republic of China.
Given extremely high porosity, aerogels have demonstrated remarkable advantages in serving as thermal insulation and wave-transparent materials. Unfortunately, their practical applications are greatly confined by their inherent fragility. The recent emergence of polymer aerogels presents an ideal platform for the development of flexible aerogel films.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
College of Grain Science and Technology, Shenyang Normal University, Shenyang 110034, China. Electronic address:
In this experiment, we investigated the structural properties, digestibility, and variations in antioxidant activity of rice bran-tissue peanut protein (RB-TPP), which was created through high-moisture extrusion between peanut protein powder (PPP) and various additions (0 %, 5 %, 10 %, 15 %, and 20 %) of rice bran (RB). The disulfide bonding and hydrophobic interactions were strengthened, and the hydrogen bonding in the RB-TPP was weakened by adding 5-10 % RB. Additionally, the β-sheet content reached its maximum at RB-10 %, which allowed the hydrophobic groups to be encapsulated ina stable protein network fiber structure, enhancing degree of organization, the thermal stability and digestibility of RB-TPP.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia. Electronic address:
UV-irradiation is a stress factor for proteins, leading to disruption of their native structure. Test systems based on UV-irradiated proteins are relevant for researchers, as they allow working directly with damaged protein molecules, which can be important when studying the properties and mechanisms of action of various antiaggregation agents. The study of UV-irradiated proteins can also have applied significance, including medical.
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