6203-18-5Relevant articles and documents
A Difluoroboron β-Diketonate Probe Shows turn-on Near-Infrared Fluorescence Specific for Tau Fibrils
Park, Kwang-Su,Kim, Mi Kyoung,Seo, Yujin,Ha, Taewoong,Yoo, Kyeongha,Hyeon, Seung Jae,Hwang, Yu Jin,Lee, Junghee,Ryu, Hoon,Choo, Hyunah,Chong, Youhoon
, p. 2124 - 2131 (2017)
Tau aggregation in neuronal cells has recently received significant attention as a robust predictor of the progression of Alzheimer's disease (AD) because of its proven correlation with the degree of cognitive impairment in AD patients. Accordingly, noninvasive imaging of tau aggregates has been highlighted as a promising diagnostic tool for AD. We have previously identified a tau-specific turn-on near-infrared fluorescent (NIRF) probe (1), and, in this study, structural modification was performed to optimize its physicochemical as well as fluorescence properties. Thus, a series of fluorescent dyes (2a-2j) composed of a variously substituted difluoroboron β-diketonate and an N,N-dimethylaniline moiety linked by a length-extendable π-bridge were prepared. Among those, isobutyl-substituted difluoroboron β-ketonate with a π-conjugated 1,4-butadienyl linker (2e) showed the most promising properties as a tau-specific NIRF probe. Compared with 1, the turn-on fluorescence of 2e was more specific to tau fibrils, and it showed 8.8- and 6.2-times higher tau-over-Aβ and tau-over-BSA specificity, respectively. Also, the fluorescence intensity of 2e upon binding to tau fibrils was substantially higher (~2.9 times) than that observed from 1. The mechanism for tau-specificity of 2e was investigated, which suggested that the molecular rotor-like property of 2e enables specific recognition of the microenvironment of tau aggregates to emit strong fluorescence. In transgenic cell lines stably expressing GFP-tagged tau proteins, 2e showed good colocalization with tau-GFP. Moreover, the fluorescence from 2e exhibited almost complete overlap with p-Tau antibody staining in the human AD brain tissue section. Collectively, these observations demonstrate the potential of 2e as a tau-specific fluorescent dye in both in vitro and ex vivo settings.
Method for preparing olefine aldehyde by catalyzing terminal alkyne or terminal conjugated eneyne and diphosphine ligand used in method
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Paragraph 0126-0132, (2021/05/29)
The invention discloses a method for preparing olefine aldehyde by catalyzing terminal alkyne or terminal conjugated eneyne and a diphosphine ligand used in the method. According to the invention, indole-substituted phosphoramidite diphosphine ligand which is stable in air and insensitive to light is synthesized by utilizing a continuous one-pot method, and the indole-substituted phosphoramidite diphosphine ligand and a rhodium catalyst are used for jointly catalyzing to successfully achieve a hydroformylation reaction of aromatic terminal alkyne and terminal conjugated eneyne under the condition of synthesis gas for the first time, so that an olefine aldehyde structure compound can be rapidly and massively prepared, and particularly, a polyolefine aldehyde structure compound which is more difficult to synthesize in the prior art can be easily prepared and synthesized, and a novel method is provided for synthesis and modification of drug molecules, intermediates and chemical products.
Aromatic amines in organic synthesis. Part ii. p‐aminocinnamaldehydes
J?drzejewska, Beata,Pietrzak, Marek
, (2021/08/03)
Ten derivatives of p‐aminocinnamic aldehydes were prepared from the reaction of either aromatic amines with dimethylaminoacrolein or benzaldehydes with acetaldehyde. Their chemical structure and purity were verified by1H NMR,13C NMR and IR spectroscopic methods. We found that the synthesis applying dimethylaminoacrolein as the reagent gets better yields than the one based on the reaction with acetaldehyde. The yields of the cinnamic aldehydes varied according to the type of the amino group and the number and position of the substituents. The basic spectroscopic properties of the p‐aminocinnamic aldehydes are also described since the compounds may be a precursor for the synthesis of dyes for diverse applications, e.g., in medicine and optoelectronics.