CCS Chemistry, Ahead of Print.
The installation of a trifluoromethyl group onto a nitrogen atom can effectively modulate the basicity of amines owing to the strong electron-withdrawing effect of fluorine. Nevertheless, efficient and operationally simple methods for N-trifluoromethylation of amines are yet to be developed. This protocol involves the use of readily available secondary amines as starting materials, along with CS2 and AgF as the N-trifluoromethylation reagents, enabling the target molecules to be synthesized in a single step. The versatility of our method was demonstrated by successfully synthesizing N,N-dialkyl and N-(hetero)aromatic N-CF3-containing compounds with various substituents. Moreover, this methodology has been successfully applied to the late-stage modification of complex bioactive molecules, facilitating the synthesis of N-CF3 drug bioisosteres and N-CF3-tailored amino acids, which would broadly stimulate the drug discovery of N-CF3 containing molecules.
Two structurally analogous self-assembled bowl-shaped hosts were obtained in close to quantitative yields via hydrazone condensation in acidic aqueous media, where the dynamic nature of hydrazone bonds was activated. Each bowl bears nine positive charges, endowing it with good water solubility. The bowls can thus take advantage of the hydrophobic effect and/or electrostatic forces to recognize neutral or anionic guests. Upon being accommodated within the host cavity, an anthracene derivative was protected from UV-stimulated oxidation.
A novel method for enhanced resolution, termed expansion mass spectrometry imaging, has been developed for lipid mass spectrometry imaging, utilizing existing commercially available mass spectrometers without necessitating modifications. This approach involves embedding tissue sections in a swellable polyelectrolyte gel, with the target biomolecules indirectly anchored to the gel network. By employing matrix-assisted laser desorption ionization mass spectrometry imaging, the method has realized an enhanced spatial resolution that surpasses the conventional resolution limits of commercial instruments by approximately 4.5 fold. This enhancement permits the detailed visualization of intricate structures within the mouse brain at a subcellular level, with a lateral resolution nearing 1 μm. As a physical technique for achieving resolution beyond standard capabilities, this readily adaptable approach presents a powerful tool for high-definition imaging in biological research.
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：