7 -Nitrobenz-2-oxa-1,3-diazole

Heterocyclic fluorophores based on the benzoxadiazole nucleous, namely 4-nitrobenz-2-oxa-l,3-diazole (NBD) 14 derivatives/analogs, have been widely used as derivatization reagents for analysis purposes. Examples include the amino- or thiol reactive 4-fluoro-7-nitrobenz-2-oxa-l,3-diazole (NBD-F) 15 and 4-chloro-7-nitrobenz-2-oxa-1,3-diazole (NBD-C1) 16 [45-50] and the thiol-reactive /V-((2-(iodoacetoxy)ethyl)-/V-methyl)amino-7-nitrobenz-2-oxa-1,3-dia-zole (IANBD ester) 17 [51] and 7-chlorobenz-2-oxa-l,3-diazole-4-sulfonate (SBD-C1) 18 [52], NBD-F and NBD-C1 derivatives can be excited at about 470 nm by using the relatively inexpensive and reliable argon ion lasers or newer diode pumped solid state (DPSS) lasers. NBD-F has been used as a labeling tag in various capillary electrophoresis (CE) experiments for amino acids [53-57] including the monitorization of in vivo dynamics of amino acids neurotransmitters [58]. 

Ramachandram B, Samanta A (1998) Transition metal ion induced fluorescence enhancement of 4-(N,N-dimethylethylenediamino)-7-nitrobenz-2-oxa-1,3-diazole. J Phys Chem A 102 10579-10587... 

PAHs polycyclic aromatic hydrocarbons. FITC fluorescein isothiocyanate. DNS dansyl halide. OPA o-phthaldialdehyde. NBD 4-clair-7-nitrobenz-2-oxa-1,3-diazole. YOYO-1 benzoxazolium-4-quinolinium dimer. NAD" nicotinamide adenine dinucleotide. 

The feasibility of the screening scheme of fluorescent RNP sensors (Fig. 10.4) was demonstrated by utilizing libraries of fluorescent RNP receptors constructed from the 29 different ATP-binding RNP, which obtained from RRE30N RNAs (Fig. 10.2a) and Rev peptides modified with various fluorophores, 7-methoxycoumarin-3-carboxylic acid (7mC-Rev), 4-fluoro-7-nitrobenz-2-oxa-1,3-diazole (NBD-Rev), and Cy5 mono NHS ester (Cy5-Rev) at the N-terminal. Complex formation of the 29 different RNA subunits and Pyr-Rev, 7mC-Rev, NBD-Rev, or Cy5-Rev afforded four independent fluorescent RNP libraries. 

CA-NBD (7-nitrobenz-2-oxa-1,3-diazole cholate) DCA-NBD (7-nitrobenz-2-oxa-1,3-diazole deoxycholate] LCA-NBD (7-nitrobenz-2-oxa-1,3-diazole lithocholate) UDCA-NBD (7-nitrobenz-2-oxa-1,3-diazole ursodeoxycholate)... 

SCN, Isothiocyanate OSu, succinimidyl active ester lAA, iodoacetamide MAL, maleimide SO Cl, sulfonyl chloride Cl, active halogen group —SS—, disulfide exchange reaction involving SPDP [A/-succinimidyl 3-(2-pyridyldithio)propionate)] NBD, 7-nitrobenz-2-oxa-1,3-diazole DAPI, 4, 6-diamidino-2-phenylindole DCDHB, dicyanodihydroxybenzene PBS, phosphate-buffered saline. 

Other Names Hexanamide, (V-[2-hydroxy-l-(hydroxymethyl)-3-heptadecenyl]-6-[(7-nitro-2,l,3-benzoxadiazol-4-yl)amino]- Hexanamide, iV-[2-hydroxy-1 -(hydroxymethyl)-3-heptadecenyl]-6-[(7-nitro-4-benzofurazanyl)amino]- 2,1,3-Benzoxadiazole, hexanamide deriv. 6-((N-(7-Nitrobenz-2-Oxa-l,3-Diazol-4-yl)amino)hexanoyl)Sphingosine N-(6-[(7-nitrobenzo-2-oxa-1,3-diazo 1 -4-yl)amino] caproy 1 )-sphingosine ... 

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