title: Synthesis, X-ray crystal structure and fluorescent spectra of novel pyrazolo[1,5-a]pyrazin-4(5H)-one derivatives.
abstract: A series of fluorescent compounds, containing pyrazolo[1,5-a]pyrazin-4(5H)-one moiety, were designed and synthesized from ethyl 1-(2-oxo-2-phenylethyl)-3-phenyl-1H-pyrazole-5-carboxylates. The structures of the compounds have been confirmed by IR, (1)H NMR, HRMS and X-ray crystal diffraction. The optical properties of the compounds were investigated by UV-vis absorption and fluorescence spectroscopy. The effect of pH on the UV-vis absorption of compound 2a in methanol-H(2)O solutions was studied and interpreted by theory calculation. The pK(a) value of compound 2a was determined by the absorption spectra.
authors: Institute of Organic Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, PR China.
authors: Liang-Wen
authors: LW
authors: Zheng
authors: Zhong-Liang
authors: ZL
authors: Gong
authors: Wen-Long
authors: WL
authors: Liu
authors: Ying-Rui
authors: YR
authors: Liu
authors: Bao-Xiang
authors: BX
authors: Zhao
mesh_terms: D018360:Crystallography, X-Ray; D008954:Models, Biological; D008958:Models, Molecular; D056004:Molecular Dynamics Simulation; D015394:Molecular Structure; D011719:Pyrazines / Q000138:chemical synthesis / Q000737:chemistry*; D011720:Pyrazoles / Q000138:chemical synthesis / Q000737:chemistry*; D011725:Pyridines / Q000138:chemical synthesis* / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods
chemical_list: D011719:Pyrazines; D011720:Pyrazoles; D011725:Pyridines; C447480:pyrazolo(3,4-b)pyridine