7-Chloro-4-nitrobenzo-2-oxa-l,3-diazole

Phenols 7-Chloro-4-nitrobenzo-2-oxa-l,3-diazole (NBD chloride) Fluorescent 4-nitrobenzofuran derivatives are produced. Primary and secondary aromatic amines and thiols also react. [3]... 

A more comprehensive approach was reported in 1975 by Brabander and Verbeke (612). In this method, tissue samples were extracted with methanol and the acidified extract defatted with petroleum ether to be loaded onto a Dowex 50W-X8 anion-exchange resin. Following elution with aqueous methanol, the concentrated buffered extract was further defatted with diethyl ether. The sample was derivatized with 7-chloro-4-nitrobenzo-2-oxa-l,3-diazole (NBD-Cl) to be further spotted on a silica high-performance thin-layer chromatographic plate developed in two dimensions using chloroform/ethanol and chloroform/propionic acid consecutively as eluents. Detection of the propylthiouracil, phenylthiouracil, and tapazole residues was carried out on the basis of the fluorescence induction of the NBD derivatives of the drugs with an alkaline cysteine solution. 

Abbreviations CDNB, l-chloro-2,4-dinitrobenzene GSH, glutathione GS-DNB, l-(S-glutathionyl)-2,4-dinitrobenzene GST, glutathione-S-transferase NBD-C1, 7-chloro-4-nitrobenzo-2-oxa-l,3-diazole EA, ethacrynic acid. 

H -ATP-synthase was postulated in view of the evidence that illumination [58,59], respiration [60] or artificially imposed ApH of the right direction (inside alkaline) [61] can increase the ATP level in halobacterial cells. This process was shown to be sensitive to A-ethylmaleimide, nitrate, A, A -dicyclohexylcarbodiimide (DCCD) and 7-chloro-4-nitrobenzo-2-oxa-l,3-diazole (NBD-Cl), and resistant to vanadate and azide. The same inhibitor pattern was found to be inherent in 350 kDa ATPase isolated from H. halobium[63] and H. saccharovorum [64,65],... 

Ghosh PB, Whitehouse MW. 7-Chloro-4-nitrobenzo-2-oxa-l,3-diazole a new fluori-genic reagent for amino acids and other amines. Biochem J 1968 108 155-6. 

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