81432-12-4

Upstream product

• 10199-89-0 NBD chloride 
• 147-85-3 L-proline 
• 18333-73-8 4-methoxy-7-nitro-benzo[1,2,5]oxadiazole 
• 608-31-1 2,6-Dichloroaniline 
• 7116-16-7 4-chloro-2,1,3-benzoxadiazole 
• 5509-65-9 2,6-difluoroaniline 
• 29270-54-0 1,3-difluoro-2-nitrosobenzene 
• 1194-66-7 2,6-dichloronitrosobenzene 
• 29270-56-2 4-fluoro-7-nitro-2,1,3-benzoxadiazole 
• 29270-55-1 4-fluoro-2,1,3-benzoxadiazole 

Relevant academic research and scientific papers

One-pot fluorescent labeling protocol for complex hydroxylated bioactive natural products

Tagging of small bioactive molecules with a fluorophore is a highly sensitive method to trace their cellular activities through real-time visual information. Here we disclose a 7-nitrobenzo-2-oxa-1,3-diazole (NBD)-based, high-yielding, one-pot labeling protocol for hydroxylated molecules using Yamaguchi coupling as the key reaction. This methodology was successfully applied on several sensitive and complex hydroxylated bioactive compounds including 7-deacetylazadiradione, simvastatin, camptothecin, andrographolide, cinchonine, β-dihydroartemisinin, and azadirachtin A. Further, utility of this protocol was illustrated on the cytotoxic activity of azadiradione derivatives against several cancer cell lines through cell imaging of two qualified fluorescent probes.

Improved synthesis of 4-amino-7-nitrobenz-2,1,3-oxadiazoles using NBD fluoride (NBD-F)

The 7-nitrobenz-2,1,3-oxadiazole (NBD) unit is a highly useful fluorescent tag with wide application in biology. Installation of the NBD group typically proceeds via the SNAr reaction between an amine and an NBD halide. Herein, we demonstrate that NBD-F 1 results in significantly higher yields than NBD-Cl 2, and that triethylamine in dimethylformamide at 23 °C overnight is a broadly applicable set of conditions for this reaction. In particular, the highly useful fluorescent carbohydrate 2-NBD-glucosamine (2-NBDG, 3) can now be prepared in 75% yield with NBD-F as compared to 12% with NBD-Cl.

KINETIC RELATIONS IN THE FORMATION OF DERIVATIVES OF SOME AMINO ACIDS WITH 7-CHLORO-4-NITRO-2,1,3-BENZOXADIAZOLE AND ITS ANALOGS

The reactions of 7-chloro-4-nitro-2,1,3-benzoxadiazole and its analogs with proline, 4-hydroxyproline, and glycine in a weakly alkaline medium proceed through both anionic and zwitterionic forms of the substrate.Acceleration of the reaction in the pH range 7.5-9.5 is accounted for by the increasing content of the anionic form, which reacts more readily.