An environmentally friendly and efficient method was developed for one-pot synthesis of a series of 2H-phenanthro[9,10-c]pyrazoles in EtOH by two dehydration processes. Firstly, 3,4-diaryl-1H-pyrazoles were synthesized by the cyclocondensation of isoflavones and hydrazine hydrate in refluxing EtOH. Secondly, the final target products 2H-phenanthro[9,10-c]pyrazoles were given by photocyclization and dehydration of 3,4-diaryl-1H-pyrazoles in 1 : 1 (v/v) EtOH-H 2 O. The advantages of this method are catalyst-free, short synthetic routes, mild reaction conditions and easy work-up. In addition, the fluorescence properties of 2H-phenanthro[9,10-c]pyrazoles were determined. Scheme 1 The retrosynthetic analysis of 2H-phenanthro[9,10-c]pyrazoles. † Electronic supplementary information (ESI) available: 1 H NMR, 13 C NMR and HRMS spectra for all compounds.

Background: The prevalence of allergen sensitization varies in different geographic areas and population subsets. This study investigated the prevalence and distribution of inhaled and food allergens among allergic patients in Henan Province, China.

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Water-soluble daidzein derivatives, [Ni(H 2 O) 6 ](C 16 H 11 O 4 SO 3 ) 2 ·10H 2 O and [Zn(H 2 O) 6 ] (C 16 H 11 O 4 SO 3 ) 2 ·10H 2 O (C 16 H 11 O 4 SO 3 , 7-methoxy-4 -hydroxylisoflavone-3 -sulfonate) were synthesized and their crystal structures were determined by X-ray diffraction analysis. The crystals of them all belong to triclinic crystal system, space group P1. The results show that the two derivatives consist of metal cation [Ni(H 2 O) 6 ] 2+ and [Zn(H 2 O) 6 ] 2+ , anion C 16 H 11 O 4 SO 3 − and H 2 O. Ni 2+ and Zn 2+ are the centers of the two compounds, respectively. A hydrophilic region is built by a variety of hydrogen bonds among [Ni(H 2 O) 6 ] 2+ or [Zn(H 2 O) 6 ] 2+ , C 16 H 11 O 4 SO 3 −and the lattice water molecules. Aromatic π -π stacking interactions assemble the isoflavone skeletons into a column and the columns form a hydrophobic region of daidzein derivatives. The sulfo-groups bridge the hydrophilic and hydrophobic region as well as the inorganic and organic components.