88861-53-4

Upstream product

• 54711-39-6 7-(diethylamino)-2-oxo-2H-1-benzopyran-4-carboxaldehyde 
• 54711-38-5 7-(diethylamino)-4-(hydroxymethyl)-2H-chromen-2-one 
• 65-85-0 benzoic acid 
• 88861-39-6 C₂₁H₂₃N₃O₄S 
• 91-44-1 7-diethylamino-4-methylcoumarin 
• 88861-43-2 4-(diazomethyl)-7-(diethylamino)coumarin 

Relevant academic research and scientific papers

Coumarinylmethyl caging groups with redshifted absorption

The small and synthetically easily accessible coumarinylmethyl backbone has been modified to generate a family of photolabile protecting groups with redshifted absorption. We relied on introducing electron-donating groups in the 7 position and electron-withdrawing groups in the 2-, and 2- and 3 positions. In particular, we showed that the diethylamino-thiocoumarylmethyl and the diethylamino-coumarylidenemalononitrilemethyl are relevant for uncaging with cyan light. They both exhibit a significant action cross section for uncaging in the 470-500 nm wavelength range and a low light absorption between 350 and 400 nm. These attractive features are favorable to perform chromatic orthogonal photoactivation with UV and blue-cyan light sources, respectively. Revealing protecting groups: The coumarinylmethyl backbone was used to generate a family of photolabile protecting groups with redshifted absorption (see scheme). Several members exhibit a significant action cross section for uncaging in the 470-500 nm wavelength range and a low light absorption between 350 and 400 nm. These features are favorable for chromatic orthogonal photoactivation with UV and blue-cyan light sources, respectively.

Studies on Stable Diazoalkanes as Potential Fluorogenic Reagents. I. 7-Substituted 4-Diazomethylcoumarins

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