4-Chloro-7-nitrobenzofurazan (NBD-chloride) was used in the following studies, Synthesis of fluorescent phospholipid-derivative, NBD-didecanoylphosphatidylethanolamine, Synthesis of functionalized hydroxynaphthofurazan, Spectrophotometric and spectrofluorometric determination of clemastine hydrogen fumarate, loratadine, losartan potassium and ramipril in pharmaceutical formulations. Synthesis of 7-nitrobenzofurazan (NBD)-labeled maleimide, via Diels-Alder reaction. NBD-Cl is widely used to label peptides, proteins, drugs and other biomolecules. It is also a popular derivatizing reagent for HPLC analysis
Purify it by repeated recrystallisation from pet ether (b 40-60o). On treatment with MeONa in MeOH it gives 4-methoxy-7-nitrobenzo-2-oxa-1,3-diazole m 115-116o. [Nunno et al. J Chem Soc (C) 1433 1970.] It is a very good fluorophore for amino acids [Imai & Watanabe Analyt Chim Acta 130 377 1981], as it reacts with primary and secondary amines to form fluorescent adducts with 470nm and 530nm. It gives a glycine derivative with m 185-187o [Miyano et al. Anal Chim ex em Acta 170 81 1985]. 5-Fluorouracil (5 -fluoropyrimidinedi -2,4 -[1 H ,3 H ]-one) [51 -21 -8] M 130.1, m 282 -2 8 3o(dec), 282-286o(dec), pK 1 8.04, pK 2 13.0. Recrystallise it from H2O or MeOH/Et2O and sublime it at 190-200o/0.1mm or 210-230o/0.5mm. UV: at 265-266nm ( 7070). [Barton et al. J Org max Chem 37 329 1972, Duschinsky & Pleven J Am Chem Soc 79 4559 1957, Beilstein 24 III/IV 1229.]