Crystal Structures of Schiff Base from 4-Aminoantipyrine and Pyridine-2-carboxaldehyde and Its Perchlorate

The Schiff base pyridine-2-carboxaldehyde-4-aminoantipyrine （CI7H16N4O 1） and its perchlorate （C17H17N4O·ClO4 2） have been prepared and characterized by elemental analysis, IR spectra and single-crystal X-ray crystallography analysis. Both 1 and 2 crystallize in the monoclinic system, space group P21/c. For 1, a = 8.6820（12）, b = 24.934（3）, c = 7.0064（10） A,, β= 97.942（3）°, V = 1502.2（4） A^3, Z = 4, Dc = 1.293 g/cm^3, F（000） = 616,μ = 0.084 mm^-1, the final R = 0.0592 and wR = 0.1244. For 2, a = 5.9302（2）, b = 20.347（7）, c = 14.663（6） A, β= 90.200（9）°, V= 1769.201） A^3, Z = 4, Dc = 1.475 g/cm^3, F（000） = 816, μ = 0.254 mm^-1, the final R = 0.0533 and wR = 0.0819. As expected, both molecular structures of 1 and 2 adopt a trans configuration about the central C=N double bond. 2 is an ionic compound with the protonation at N（1） of pyridine-2-carboxaldehyde-4- aminoantipyrine.

5-Alkylpyrrole-2-carboxaldehyde derivatives from the Chinese sponge Mycale lissochela and their PTP1B inhibitory activities

Two new 5-alkylpyrrole-2-carboxaldehyde derivatives,mycalenitrile-15（1） and mycalenitrile-16（2）,along with five known related ones（3-7）,were isolated from the South China Sea sponge Mycale lissochela.The structures of the new compounds were elucidated on the basis of extensive spectroscopic analysis and by comparison of their NMR data with those reported in the literature.In bioassay,compounds 1 and 7 exhibited significant PTPIB（Protein-tyrosine phosphatase 1B,a recognized target for diabetes and obesity） inhibitory activities with IC（50） values of 8.6 and 3.1 μmoI/L,respectively.A preliminary SAR analysis of the isolated compounds with their PTP1 B inhibitory effects was described.

Synthesis and characterization of poly(2,5-diyl pyrrole-2-pyrrolyl methine)semiconductor copolymer

The proposed technique to synthesise poly {（2,5-diyl pyrrole）（2-pyrrolyl methine）}（PPPM） copolymer by condensation of pyrrole and pyrrole-2-carboxaldehyde monomers catalyzed by Maghnite-H＋ is introduced.The protons are exchanged with Maghnite-H＋, which is available in the form of a montmorillonite silicate clay sheet. The effect of several parameters such as time and temperature of copolymerization, [pyrrole]/[pyrrole-2-carboxaldehyde] molar ratio, amount of Maghnite-H＋, and solvent on the produced poly（2,5-diyl pyrrole-2-pyrrolyl methine） semiconductor copolymer material（yield%） was investigated. The synthesized PPPM copolymer was characterized using nuclear magnetic resonance, Fourier transform infrared, and ultraviolet-visible spectroscopy.The results show that the synthesized copolymer using the copolymerization technique is a real organic copolymer consisting of two monomers units（i.e, pyrrole and pyrrole-2-carboxaldehyde）. Also, the synthesized copolymer is more soluble than polypyrrole in most of the commonly used organic solvents. Hence, copolymerization of pyrrole with pyrrole-2-carboxaldehyde will overcome the insolubility of polypyrrole. In addition, the resultant copolymer exhibits good film formability. The produced copolymer has several potential applications in the field of rechargeable batteries, sensors, capacitors, light emitting diodes, optical displays, and solar cells.