Stable (N-aryl)- and (N-alkyl)dialkylsilaketenimines R2SiCNR' [R = 1,1,4,4-tetrakis(trimethylsilyl)butane-1,4-diyl, R' = 2,6-diisopropylphenyl (2a) and 1-adamantyl (2b)] were synthesized as blue and red crystals by the reactions of isolable dialkylsilylene 3 with 2,6-diisopropylphenyl isocyanide and 1-adamantyl isocyanide. X-ray single-crystal analysis disclosed that molecular structures of 2a and 2b were close to each other and were characterized to be allenic rather than zwitterionic or a silylene-isocyanide complex. The bonding characteristics of silaketenimines are found to be affected strongly by the substituents on silicon and nitrogen atoms. Remarkable red-shift of the pi(Si=C) --> pi*(C=N) band of 2a [lambdamax/nm (epsilon) 647(156)] compared with that of 2b [465 nm (109)] is ascribed to lowering of the pi*(C=N) orbital level due to significant interaction between pi*(C=N) and pi*(N-aryl) orbitals.
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http://dx.doi.org/10.1021/ja057917o | DOI Listing |
Lasers Med Sci
January 2025
Hangzhou Third People's Hospital, Hangzhou, China.
Background: Post-inflammatory hyperpigmentation (PIH) is a common cosmetic concern, often leading to significant psychological distress for the patients. With the widespread application of lasers including ablative fractional resurfacing (AFR) with a 10,600 nm CO laser, PIH caused by lasers is becoming increasingly common. But due to the absence of an appropriate animal research model, our understanding of pathophysiological mechanisms and preventive strategies for PIH remains limited.
View Article and Find Full Text PDFClin Exp Rheumatol
January 2025
Institute of Rheumatology, and Department of Rheumatology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic.
Objectives: This study aimed to investigate the associations between radiographic damage, serum biomarkers, and clinical assessments in Czech patients with hand osteoarthritis (HOA) over a five-year follow-up period.
Methods: The study cohort comprised 129 patients diagnosed with HOA, including 72 patients with an erosive subtype and 57 patients with a non-erosive subtype. Radiographs were evaluated using the Kallman scoring system by two independent readers.
FEMS Microbiol Ecol
January 2025
Ecology and Genetics Research Unit, PO Box 3000, University of Oulu, FI-90014 Oulu, Finland.
The physical and chemical properties of wild berry fruits change dramatically during development, and the ripe berries host species-specific endophytic communities. However, the development of fungal endophytic communities during berry ripening is unknown. We studied bilberries (Vaccinium myrtillus L.
View Article and Find Full Text PDFPhysiol Res
December 2024
Laboratory of Neurobiology and Molecular Psychiatry, Department of Biochemistry, Faculty of Science, Masaryk University, Brno, Czech Republic.
The global COVID-19 pandemic, caused by SARS-CoV-2, has led to significant morbidity and mortality, with a profound impact on cardiovascular health. This review investigates the mechanisms of SARS-CoV-2's interaction with cardiac tissue, particularly emphasizing the role of the Spike protein and ACE2 receptor in facilitating viral entry and subsequent cardiac complications. We dissect the structural features of the virus, its interactions with host cell receptors, and the resulting pathophysiological changes in the heart.
View Article and Find Full Text PDFACS Nano
January 2025
Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Drive, Los Angeles, California 90095-1569, United States.
Dimension-engineered synthesis of atomically thin II-VI nanoplatelets (NPLs) remains an open challenge. While CdSe NPLs have been made with confinement ranging from 2 to 11 monolayers (ML), CdTe NPLs have been significantly more challenging to synthesize and separate. Here we provide detailed mechanistic insight into the layer-by-layer growth kinetics of the CdTe NPLs.
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