Synthesis and Applications of Selected Fluorine-Containing Fluorophores

Abstract

The synthesis of fluorine-containing small molecules has had numerous benefits of improving the quality and efficiency of many applications of these compounds. For example, fluorine adds promising functionalities in various areas of imaging (MRI, PET, and NIR); gives cell-targeting properties; and has demonstrated improvements in cell permeability, solubility, and other pharmacologic properties. For these and other numerous reasons, fluorination of molecules has grown in popularity in various fields of chemistry. Many reports show the effects observed from increasing the number of fluorine atoms on a fluorophore scaffold. This report will cover the most significant applications and improvements that fluorine has contributed to in various dye scaffolds such as BODIPY, rhodamine, phthalocyanine, and cyanine in the recent decade.

Reaction-based fluorogenic probes for selective detection of cysteinyl oxidation in living cells

“…Reaction of the phenaline-1,3-dione scaffold at nucleophilic C-2 with the electrophilic sulfur atom in sulfenic acid serves to stabilize the fluorogenic enol tautomer. A second key contributor to the fluorescence of these probes is the electron-withdrawing fluorine atom attached to the naphthalene core, which serves to stabilize the excited state 27 . A final feature of CysOx probes is the push-pull system wherein the electron-donating amino group is in conjugation with fluorine via the intervening p-system 28 .…”

A Novel Fluorogenic Assay for the Detection of Nephrotoxin-Induced Oxidative Stress in Live Cells and Renal Tissue

“…Additionally, it is known that adding fluorine or trifluoromethyl groups to a fluorophore scaffold typically improves its photochemical stability. 15 , 17 , 18 Therefore, a trifluoromethyl derivative of CH, TFCH ( Figure S1 ), was designed to be an efficient live cell compatible probe that can detect low levels of biomolecule carbonylation resulting from mild nephrotoxicity.…”

“…Substitution of the methyl group of CH with a trifluoromethyl group was anticipated to have little effect on the physical properties of the probe while improving its photochemical properties. , A trifluoromethyl substituent at C-4 is known to strongly red shift the absorption and emission envelopes of related aminocoumarins, , which allows greater accessibility of the commonly used 405 nm laser line. Additionally, it is known that adding fluorine or trifluoromethyl groups to a fluorophore scaffold typically improves its photochemical stability. ,, Therefore, a trifluoromethyl derivative of CH, TFCH (Figure S1), was designed to be an efficient live cell compatible probe that can detect low levels of biomolecule carbonylation resulting from mild nephrotoxicity.…”

Rhodamine Fluorophores for STED Super‐Resolution Biological Imaging

“…Fluorine substitution can not only affect the transition between zwitterionic (fluorescent) and spirolactone (non-fluorescent) forms, but also change the staining performance on membranous structures. [28] In addition, a rhodamine containing 3-carboxy-4,5,6,7-tetrafluorophenyl group (8) can undergo region selective displacement of F-6' by thiols and amines, which offers a way for the functional groups for bioconjugation to be introduced. [24] Fluorophores with NIR fluorescence (650-900 nm) have significant advantages in biological imaging due to low background fluorescence interference of biomolecules and deep tissue penetration.…”