9-Aryl-3-aminocarbazole as an Environment- and Stimuli-Sensitive Fluorogen and Applications in Lipid Droplet Imaging

Abstract

Environment-sensitive luminophoric molecules have played an important role in the fields of smart materials, sensing, and bioimaging. In this study, it was demonstrated that depending on the substituents, 9-aryl-3-aminocarbazoles can display aggregation-induced emission and solvatofluorochromism, and the operating mechanism was clarified. The application of these compounds to lipid droplet imaging and fluorescent probes for cysteamine was demonstrated.

Photocatalytic Reductive C–O Bond Cleavage of Alkyl Aryl Ethers by Using Carbazole Catalysts with Cesium Carbonate

“…After 24 h of irradiation using a light-emitting diode (LED) lamp (λ = 400 ± 20 nm), phenol ( 2a ) was obtained in 11% yield and unreacted 1a was recovered (entry 1). Next, we replaced PC1 with the N –H variant PC3 , the synthesis of which was previously developed by our group . This led to a 23% increase in the yield of 2a (entry 2), and therefore, we conducted subsequent investigations with PC3 .…”

Tunable Wavelength, High-Brightness, and NIR-II Emission Phenanthridinium-Based Heptamethine Dyes for High-Contrast Vascular and Intestinal Imaging In Vivo

“…On the molecular design strategy, synthesis of phenanthridinium dyes with desired photophysical properties also requires the implementation of a flexible and robust synthetic strategy. In order to achieve functionalization at the 2′ position of phenanthridone, three distinct substitution strategies were employed: (1) Nitration at the 2′-position, followed by palladium-catalyzed hydrogenation to form an amino group, and subsequent reaction with haloalkanes to yield 6a–c. − (2) Bromination at the 2′-position, followed by Buchwald–Hartwig coupling with secondary amines to obtain 6d–f . (3) Suzuki coupling to synthesize 6g, which was subsequently subjected to treatment with a methyl nucleophile to generate the desired phenanthridinium 7a–g. , The final step in the synthesis involved utilization of the Knoevenagel condensation to construct the target YH dyes.…”