Synthesis and fluorescent properties of some heterobifunctional and rigidized 7‐aminocoumarins

Abstract

Heterobifunctional fluorescent reagents of coumarin type are synthesized. They possess, in position 7, a rigidized or un‐rigidized amino group and, in position 3 or 4, a carboxylic function. The fluorescence characteristics of these compounds are described and compared with the 7‐amino‐4‐methylcoumarin. The influence of the relative freedom of rotation of the amino group or the position of the acid function on the fluorescence properties are also studied.

Einzelsubstanzbibliotheken organischer Materialien: Parallelsynthese und Screening von Fluoreszenzfarbstoffen

“…21 Folgende „Hits“ konnten dabei identifiziert werden (Abbildung 2): 5 A 9 ( ϕ f =0.18, λ abs =373 nm, λ em =535 nm), 8 A 2 ( ϕ f =0.90, λ abs =395 nm, λ em =478 nm), 7 C 4 ( ϕ f =0.62, λ abs =393 nm, λ em =480 nm) und 7 B 1 ( ϕ f =0.98, λ abs =397 nm, λ em =455 nm). Unter diesen zeigt das 3‐Phenylethinyl‐substituierte Cumarin 7 B 1 eine noch höhere Fluoreszenzquantenausbeute als das vergleichbare und kommerziell erhältliche Cumarin 120 ( ϕ f =0.88, λ abs =354 nm, λ em =435 nm in Ethanol) 22. Im Hinblick auf mögliche Anwendungen dieser Verbindungen z.…”

Synthesis of New Double (Spin and Fluorescence) Sensor Reagents and Labels.

“…The quenching effect can be attributed to an intramolecular charge transfer as a band at 488 nm indicates in ultraviolet/visible (UV) spectrum of 3b (and no such band in apolar dioxane). Because the advantageous effect of an amino or N,Ndialkylamino group in coumarin dyes regarding the fluorescence properties [15], paramagnetic amine (5) was treated with 3-carboxy-7-dimethylaminocoumarin imidazolide made in situ [16] from 4 [17] and 1,1'-carbonyldiimidazole (CDI) in CH 2 Cl 2 , affording compound 6a which could also be converted to compound 6b with Fe powder/glacial acetic acid. Compounds 6a and 6b exhibited longer (460 nm) wavelength fluorescence emission and there is a 25-fold difference in the fluorescence intensities of diamagnetic 6b and paramagnetic 6a forms.…”

“…solution was basified with solid NaHCO 3 or K 2 CO 3 . The mixture was extracted with CHCl 3 (3 x 15 3-Hydroxymethyl-4-(pyren-1-yl)-2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrole (15). 3-Formyl-1-oxyl-4-(pyren-1-yl)-2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrole Radical (11).…”

Intrinsic Fiber Optic pH Sensor for Measurement of pH Values in the Range of 0.5–6

“…7-Vinylbezylaminocoumarin-4-carboxylic acid (7-VBACC) was prepared by hydrolyzing methyl 7-vinylbenzylaminolcoumarin-4-carboxylate which was synthesized from methyl 7-aminocoumarin-4-carboxylate [33] …”