88861-39-6Relevant articles and documents
A visible and near-infrared light activatable diazocoumarin probe for fluorogenic protein labeling in living cells
Yang, Dan,Dai, Sheng-Yao
, p. 17156 - 17166 (2020)
Chemical modification of proteins in living cells permits valuable glimpses into the molecular interactions that underpin dynamic cellular events. While genetic engineering methods are often preferred, selective labeling of endogenous proteins in a complex intracellular milieu with chemical approaches represents a significant challenge. In this study, we report novel diazocoumarin compounds that can be photoactivated by visible (430-490 nm) and nearinfrared light (800 nm) irradiation to photo-uncage reactive carbene intermediates, which could subsequently undergo an insertion reaction with concomitant fluorescence "turned on". With these new molecules in hand, we have developed a new approach for rapid, selective, and fluorogenic labeling of endogenous protein in living cells. By using CA-II and eDHFR as model proteins, we demonstrated that subcellular localization of proteins can be precisely visualized by live-cell imaging and protein levels can be reliably quantified in multiple cell types using flow cytometry. Dynamic protein regulations such as hypoxia-induced CA-IX accumulation can also be detected. In addition, by two-photon excitation with an 800 nm laser, cell-selective labeling can also be achieved with spatially controlled irradiation. Our method circumvents the cytotoxicity of UV light and obviates the need for introducing external reporters with "click chemistries". We believe that this approach of fluorescence labeling of endogenous protein by bioorthogonal photoirradiation opens up exciting opportunities for discoveries and mechanistic interrogation in chemical biology.
Studies on Stable Diazoalkanes as Potential Fluorogenic Reagents. I. 7-Substituted 4-Diazomethylcoumarins
Ito, Keiichi,Maruyama, Junko
, p. 3014 - 3023 (2007/10/02)
As a new type of stable diazoalkane, 4-diazomethylcoumarins (4) bearing various 7-substituents were prepared for potential use in introducing fluorophores into acidic substances.Selenium dioxide oxidation of 4-methylcoumarins to the corresponding coumarin-4-carbaldehydes followed by triethylamine-mediated Bamford-Stevens reaction of their tosylhydrazones readily gave 4 as excellently stable and almost non-fluorescent crystals, exhibiting characteristic diazomethyl 1H- and 13C-nuclear magnetic resonance signals.Labeling reactions of carboxylic acids using 4 in refluxing chloroform in the presence of silica gel catalyst gave excellent yields of fluorescent coumarin-4-ylmethyl esters.In view of their stability, accessibility and fluorogenicity, these compounds (4), especially those bearing 7-methoxy and 7-acetyloxy substituents, should be practically useful fluorogenic reagents for carboxylic acids.Keywords - stable diazoalkane; 4-diazomethylcoumarin; selenium dioxide oxidation; Bamford-Stevens reaction; diazomethyl NMR; silica gel-catalyzed reaction; fluorescent esterification of carboxylic acid; coumarin-4-ylmethyl ester fluorescence
