A latent green fluorescent styrylcoumarin probe for the selective growth and detection of Gram negative bacteria

A Selective, Dual Emission β-Alanine Aminopeptidase Activated Fluorescent Probe for the Detection of Pseudomonas aeruginosa, Burkholderia cepacia, and Serratia marcescens

“…The chalcone precursor 10 (which was obtained via the previously reported aldol reaction between 2′-hydroxyacetophenone and 4- N,N -dimethylaminobenzaldehyde [24]) was cyclized using hydrogen peroxide in the presence of a base to form 4′-diethylamino-3HF 7 (Scheme 3) [24]. To obtain the linker–amino acid moiety 11 , β-alanine and the self-immolative linker precursor, 4-aminobenzylalcohol, were coupled as reported previously [15]. The mesylate of 11 was formed in situ and coupled with the fluorophore 7 , in the presence of potassium carbonate [15], to obtain the protected form of substrate 12 .…”

“…To obtain the linker–amino acid moiety 11 , β-alanine and the self-immolative linker precursor, 4-aminobenzylalcohol, were coupled as reported previously [15]. The mesylate of 11 was formed in situ and coupled with the fluorophore 7 , in the presence of potassium carbonate [15], to obtain the protected form of substrate 12 . The ether conjugation in 12 , which is acid labile due to the presence of the carbonyl group in the ortho position [25], necessitated a less acidic, two phase (ethyl acetate-water) removal of the Boc protecting group in order to obtain substrate 9 as a free amine.…”

“…A large proportion of the previously published fluorogenic enzyme substrates detect metabolic activity based on an off-to-on fluorescent signal in the blue wavelength region [12,13], however some bacterial species display autofluorescence [14], potentially interfering with the detection signal. Thus, substrates that release fluorophores emitting at higher wavelengths, such as styrylcoumarin 3 [15], or those that display a significant wavelength shift before and after hydrolysis, for example 2-aminoacridone 4 [16], have potential in bacterial detection media (Scheme 1).…”

One-Step Synthesis of Triphenylphosphonium Salts from (Het)arylmethyl Alcohols

“…(4-Nitrobenzyl)triphenylphosphonium Bromide (2b). 26 Yield: 0.24 g, 5%. All spectral data are consistent with those described above.…”

The Design and Synthesis of Fluorescent Coumarin Derivatives and Their Study for Cu2+ Sensing with an Application for Aqueous Soil Extracts

“…Some of the most readily utilized sensing methods are based on molecular probes that display concentration dependent changes in their optical properties arising from the structural changes upon interaction with the analytes of interest [11]. Coumarins are attractive for use as fluorescent optical probes, due to their easy-to-tailor structure that allows for metal ion-selective coordination sites, as well as their exhibiting significant changes in their optical signals upon interaction with such target analytes [12]. When interacting with Cu 2+ , coumarins can undergo ligand to metal charge transfer, forming a Cu 2+ –coumarin complex.…”