Nitrobenzoxadiazole

Chloro-7-nitrobenzofurazane (7-chloro-4-nitrobenzoxadiazole) [10199-89-0] M 199.6, m 96.5-97°, 97°, 99-100°. Wash the solid with H2O and recrystallise from aqueous EtOH (1 1) as pale yellow needles. It sublimes in a vacuum [UV, NMR Bolton, Gosh and Katritzky J Chem Soc 1004 1966]. 

Guminski Y, Grousseaud M, Cugnasse S et al (2009) Synthesis of conjugated spermine derivatives with 7-nitrobenzoxadiazole (NBD), rhodamine and bodipy as new fluorescent probes for the polyamine transport system. Bioorg Med Chem Lett 19 2474—2477... 

Fig. 6.8. Structures of some common fluorophores. DPH = diphenylhexatriene NBD = nitrobenzoxadiazole Tb-DTPA-csl24 = terbium diethylenetriaminepentacetate-carbostyril 124, DAPI = 4, 6-diamidino-2-phenylindole Nile red = 9-(diethylamino)-5H-benzo-[a]phenoxazin-5-one.

Nitrobenzoxadiazole. NBD derivatives are environmentally sensitive. In apolar solvents, they are highly fluorescent. When dissolved in polar solvents, the fluorescence intensity decreases significantly. Semi-empirical calculations can explain these changes of quantum yields in terms of decreased energy gaps between the... 

Kenner, R. A. and Aboderin, A. A. (1971). A new fluorescent probe for protein and nucleoprotein conformation. Binding of 7-(p-Methoxyben-zylamino) -4-nitrobenzoxadiazole to bovine trypsinogen and bacterial ribosomes. Biochemistry 10, 4433 1440. 

Amphetamine-related compounds 4-Fluoro-7 -nitrobenzoxadiazole Naphthalene-2,3-dicarboxaldehyde 76, 77... 

Naphthalene-2,3-dicarboxaldehyde Nicotinamide adenine dinucleotide N-Acetylneuraminic acid 4-Fluoro-7-nitrobenzoxadiazole Naphthalene-2,3-dicarboxaldehyde Nondestructive readout Near infrared Near infrared fluorescence Nuclear magnetic resonance 2-Nitrophenyl oxalate 1,1 -Oxalyldiimidazole Polycyclic aromatic hydrocarbon Principal component analysis Photosensitized chemiluminescence Pentachlorophenyl oxalate Polymerase chain reaction... 

Song Y, Quan Z, Evans JL, Byrd EA, Liu YM. 2004. Enhancing capillary liquid chromatography/tandem mass spectrometry of biogenic amines by pre-column derivatization with 7-fLuoro-4-nitrobenzoxadiazole. Rapid Commun Mass Spectrom 18 989. 

Figure 15.7 shows an analysis of the selectivity of2094 recent hits in high-throughput screens at Roche. Of these, almost half were specific for the screen in which they were identified as a hit - there were no other screens where these compounds had been titrated in a dose-response assay. However, 8% of the compounds had been tested in dose-response assays for more than five projects. These compounds are frequent hitters, and the most commonly occurring substructures are shown in Figure 15.8. Several of these compounds either are electrophilic, or can give electrophilic species on oxidation. The nitrobenzoxadiazoles are known fluorescent compounds. The oxindoles...

Song, Y, Shenwu, M., Zhao, S., Hou, D., and Liu, Y. M., Enantiomeric separation of amino acids derivatized with 7-fluoro-4-nitrobenzoxadiazole by capillary liquid chromatography/tandem mass spectrometry,/owmaZ o/Chroma/ograp/jy 4 1091(1-2), 102-109,2005. 

Brennan et al. used a method to detect the reaction of acetylcholineesterase with acetylcholine [46]. The method was based on the use of a monolayer, consisting of fatty acids having Ci6 chain lengths, which were covalently attached to quartz wafers and which contained a small amount of nitrobenzoxadiazole dipalmitoyl phosphatidylethanolamine (NBD-PE) (partitioned from water into the membrane). The enzyme substrate reaction produced a decrease in fluorescence intensity from the monolayer, and the detection system was sensitive to the changes in bulk concentration of as small as 0.1 pM, with a limit of detection of 2 pM of acetylcholine. The mechanism of transduction of the enzymatic reaction was investigated using spectrofluorimetric methods and fluorescence microscopy. 

In recent years nonlinear optical materials on the basis of nitroazoles, especially nitrobenzoxazoles and nitrobenzoxadiazoles, have investigated under intense scrutiny, at that and UV and fluorescence spectroscopy is widely used in studying of their structure and dynamics [1202-1225], 4-Aminosubstituted 7-nitrobenzofura-zans have a strong band in the visible region ( =457-483 nm) due to their chromophore properties [777]. 4-Substituted 7-nitrobenzofurazans possess a strong fluorescence that has led to their use as biochemical fluorescent probes in cell membranes [777, 1226-1228],... 

Hayen, H., Jachmann, N., Vogel, M., and Karst, U., LC-electron capture-APCI(-)-MS determination of nitrobenzoxadiazole derivatives. Analyst, 128, 1365-1372, 2003. 

In conclusion, the nature of the solvent can affect all the fluorescence parameters. Some examples, Table 3.3 shows the fluorescence lifetime measured with the frequency method of the nitrobenzoxadiazole dissolved in different solvents. One can notice that the fluorescence lifetime is solvent dependent. 

Table 3.3. Fluorescent lifetime of Nitrobenzoxadiazole in various solvents...

Azido-nitrobenzoxadiazole (azido-NBD) was observed to undergo a reduction reaction in the absence of an obvious reducing agent, leading to amine formation. In... 

The DMPA (Sigma, Miinchen, West Germany) was chromatographically pure. As a fluorescent tracer, dipalmitoyl-nitrobenzoxadiazol-phosphatidyl-ethanolamine (DP-NBD-PE, Avanti, Birmingham, AL) was used in a concentration of 0.25 mol%. The lipid mixture was spread from a 3 1 chloroform/ methanol solution. 

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