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The two naphthopyrones 6-methoxycomaparvin ( 1) and 6-methoxycomaparvin 5-methyl ether ( 2) were isolated from a bioactive methanol-soluble extract of the Fijian echinoderm Comanthus parvicirrus. Their structures were assigned on the basis of spectroscopic methods. X-ray diffraction analysis was used to confirm the structure of 1. Both compounds were tested for their potential to inhibit the activation of the transcription factor NF-κB, which plays an important role in cancer development and inflammation, and the mechanism of action of the two compounds was investigated. Both naphthopyrones 1and 2completely inhibit TNF-α-induced NF-κB activation at a concentration of 300 µM by inhibiting the enzymatic activity of the kinase IKKβ.

The solution-mediated syntheses and single crystal structures of the new open-framework phases (CH3NH3)3·Zn4O(AsO4)3 and (CH3NH3)3·Zn4O(PO4)3 are reported. These compounds are built up from vertex-sharing three-dimensional “OZn4” + ZnO4 + AsO4/PO4 tetrahedral frameworks encapsulating methylammonium cations in three-dimensional channel systems. These phases are closely related to the zeolite-like M3Zn4O(XO4)3·nH2O family of phases.

The solid solution series Bi2V1-xMnxO 5.5-x(0.10≤x≤0.25) has been prepared by conventional solid-state reaction and by crystallization from the melt. After additional subsolidus annealing both procedures yielded tetragonal phases with similar structures and lattice constants, as determined by X-ray powder diffraction. Partial substitution of manganese on the vanadium sites stabilizes Bi2V1-x MnxO5.5-xin the high-temperature tetragonal (γ) structure of Bi2VO5.5 for compositions in the range 0.10≤x ≤0.25. The structures of four compositions have been investigated by combined Rietveld refinements of X-ray and neutron powder diffraction data. Further characterization studies by transmission electron microscopy, magnetic susceptibility measurements and differential thermal analysis are described.