No abstract

The reaction of aqueous solutions of K2PdCl4 and K3Co(CN)6 results in gellike polymeric materials, characterized by bridging cyanides between the central metals of the adducts. These materials tend to be rigid in nature but contain in excess of 95% water by weight. We refer to these novel transition metal based hydrogels as cyanogels. In contrast to classic inorganic hydrogels these materials are not based on an oxide network. Dehydration of the cyanogels results in amorphous xerogels which maintain the initial polymeric structure of the cyanogel. Thermal processing of gels containing palladium and cobalt centers under an inert atmosphere at temperatures between 200 and 500 °C, produces a new metastable material. Sintering between 500 and 1000 °C produces ferromagnetic alloys, while processing under oxygen in the same temperature region gives the ceramic mixed oxide material PbCoO2, having the delafossite structure.

No abstract

No abstract

No abstract

No abstract

No abstract

In the title compound, 4-(3-carboxy-l-cyclopropyl-6 -fluoro-1,4-dihydro -4-oxo-7 -quinolinyl ) -1 -piperazinium-magnesium hexahydrate-sulfate-water(1/0.5/1/3), (Ci7H19FN303)[Mg(H20)6]0.5SOa.3H20, the Mg 2+ ion lies on a twofold axis and adopts a nearly regular octahedral geometry. The quinolone is protonated at the terminal N atom of the piperazine residue. The H atom of the carboxylic acid group is hydrogen bonded to the carbonyl O atom, thus preventing the bonding of the metal to this part of the molecule. CommentThe title quinolone, ciprofloxacin [cf; 1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-( 1 -piperazinyl)-3-quinolinecarboxylic acid] is a fluoroquinolone antibacterial agent with a wide spectrum of activity. It is known that the absorption of all quinolones appears to be significantly reduced by magnesium and aluminium antacids. Several other cations interact in a similar manner and the cause is probably chelation between the quinolone and the metal ion (Polk, 1989;Kara, Hasinoff, McKay & Campbell, 1991). Only a few crystal structures between quinolones and different metal ions (Ag +, Co 2+, Cu 2+) have been published