Structure and properties of silicon-silicon doubly bonded compounds (disilenes) are shown to be remarkably different from those of alkenes. X-Ray structural analysis of a series of acyclic tetrakis(trialkylsilyl)disilenes has shown that the geometry of these disilenes is quite flexible, and planar, twist or trans-bent depending on the bulkiness and shape of the trialkylsilyl substituents. Thermal and photochemical interconversion between a cyclotetrasilene and the corresponding bicyclo[1.1.0]tetrasilane occurs via either 1,2-silyl migration or a concerted electrocyclic reaction depending on the ring substituents without intermediacy of the corresponding tetrasila-1,3-diene. Theoretical and spectroscopic studies of a stable spiropentasiladiene have revealed a unique feature of the spiroconjugation in this system. Starting with a stable dialkylsilylene, a number of elaborated disilenes including trisilaallene and its germanium congeners are synthesized. Unlike carbon allenes, the trisilaallene has remarkably bent and fluxional geometry, suggesting the importance of the π-σ* orbital mixing. 14-Electron three-coordinate disilene-palladium complexes are found to have much stronger π-complex character than related 16-electron tetracoordinate complexes.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3409869 | PMC |
http://dx.doi.org/10.2183/pjab.88.167 | DOI Listing |
SLAS Discov
January 2025
Bonds Biosystems, 27 Strathmore Rd, Natick, MA, USA. Electronic address:
Obesity and type 2 diabetes (T2D) are strongly linked to abnormal adipocyte metabolism and adipose tissue (AT) dysfunction. However, existing adipose tissue models have limitations, particularly in the stable culture of fat cells that maintain physiologically relevant phenotypes, hindering a deeper understanding of adipocyte biology and the molecular mechanisms behind differentiation. Current model systems fail to fully replicate in vivo metabolism, posing challenges in adipose research.
View Article and Find Full Text PDFEnviron Pollut
January 2025
College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China.
Extracellular polymeric substances (EPS) can effectively attenuate heavy metal mobility in aquatic ecosystems and reduce metal toxicity to cells. However, a systematic study of microalgae EPS responses and their adsorption behaviors, characteristics, and mechanisms under different heavy metal exposures has not been performed. In this study, EPS extracted from Chlamydomonas reinhardtii CC-125 was analyzed for compositional changes (monosaccharides and proteins) under Cd, Cu, Pb, and Zn treatments.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China; Jiaxing Institute of Future Food, Jiaxing 314050, China. Electronic address:
Oleogels with solid-like properties can serve as substitutes for fats, thereby avoiding the consumption of high levels of saturated fatty acids. In this study, we developed a protein-polysaccharide composite network oleogel using whey protein isolate (WPI) and sodium alginate (SA) through an emulsion-templated method. Analysis with Fourier Transform Infrared (FTIR) spectroscopy confirmed the presence of hydrogen bonds and van der Waals forces between WPI and SA, which bolstered the oleogel's structure.
View Article and Find Full Text PDFFood Chem
January 2025
State Key Laboratory of Food Science and Resources, Nanchang University, 235 Nanjing East Road, Nanchang, Jiangxi 330047, China.
Due to health reasons of polyglycerol polyricinoleate (PGPR), there has been a growing interest in reducing it. To address this, this study developed the PGPR/Protein (whey, pea, and chickpea protein isolates) emulsifier combinations. The effects of these combinations on the preparation, structure, physicochemical and in vitro digestive properties of W/O/W microcapsules were evaluated.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Molecular Synthesis Center, Key Laboratory of Marine Drugs of Ministry of Education, Shandong Key Laboratory of Glycoscience and Glycotherapeutics, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China.
2-Deoxy-β-glycosides are essential components of natural products and pharmaceuticals; however, the corresponding 2-deoxy-β-glycosidic bonds are challenging to chemically construct. Herein, we describe an efficient catalytic protocol for synthesizing 2-deoxy-β-glycosides via either IPrAuNTf-catalyzed activation of a unique 1,2--positioned C2--propargyl xanthate (OSPX) leaving group or (PhO)PAuNTf-catalyzed activation of a 1,2--C2--alkynylbenzoate (OABz) substituent of the corresponding thioglycosides. These activation processes trigger 1,2-alkyl/arylthio-migration glycosylation, enabling the synthesis of structurally diverse 2-deoxy-β-glycosides under mild reaction conditions.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!