40070-83-5Relevant academic research and scientific papers
Regioselective syntheses of 2- and 4-formylpyrido[2,1-b]benzoxazoles
Li, Ke-Lai,Du, Zong-Bo,Guo, Can-Cheng,Chen, Qing-Yun
supporting information; experimental part, p. 3286 - 3292 (2009/09/08)
o-Acetaminophenols (2) reacted with Vilsmeier reagent under Meth-Cohn conditions to yield 2-formylpy-rido[2,l-6]benzoxazoles (5) unexpectedly besides the known compounds 2-(benzoxazol-2′-yl)-3-dimethylaminoacroleins (4). Refluxing 4 in acetic anhydride gave 4-formylpyrido[2,l-6]benzoxazoles (6), an isomer of 5. Both 5a and 6a were structurally characterized by X-ray crystallography. A mechanism for the formation of 5 involving sequential chlorination, dimerization, intramolecular elimination of HC1 to form the oxazole ring, formylation twice, and regioselective intramolecular nucleophilic cyclization to construct the pyridone ring is proposed.
Synthesis and fluorescence properties of 3-benzoxa- and thiazol-2-ylquinoline-5 or 7-maleimides
Nair,Rajasekharan
, p. 1944 - 1949 (2007/10/03)
Synthesis of four new 3-benzoxa/thiazol-2-ylquinolinemaleimides and their fluorescence properties are described. Among these, the 3-benzothiazol-2- ylquinoline-5-maleimide shows very good enhancement in fluorescence upon thiol addition and thus would serve as a sensitive thiol detection and quantitation reagent. Similarly, 3-benzoxazol-2-ylquinoline-7-maleimide forms a fluorescent conjugate with a model protein BSA that has good emission properties, both in the native and in the denatured state, as shown by fluorescence spectroscopy and SDS-PAGE experiments, thus indicating that 3-benzoxazol-2-ylquinoline-7- maleimide would be useful as a protein label that gives highly fluorescent protein bioconjugates.
