Cell-based Screening For Identification Of The Novel Vanadium Complexes With Multidirectional Activity Relative To The Cells And The Mechanisms Associated With Metabolic Disorders

In this study, 110 newly synthesized vanadium complexes from different structural groups were screened in three cell-based models representing the main target tissues for anti-diabetic drugs. In glucose utilization in C2C12 myocyte experiments, 93% of vanadium complexes were shown to have equal or greater activity than bis(maltolato)oxovanadium(IV) (BMOV), the methyl analog of bis(ethylmaltolato)oxovanadium(IV) (BEOV) which has been tested in clinical trials. Moreover, 49% and 50% of these complexes were shown to have equal or greater activity than BMOV in lipid accumulation in 3T3-L1 adipocytes and insulin secretion in RINm5F beta cell experiments, respectively. These results were the basis for the selection of compounds for the subsequent steps in the characterization of anti-diabetic properties. This study provides strong support for the application of screening cell-based assays with a phenotypic approach for the discovery of novel anti-diabetic drugs from the vanadium complex class. This is especially desirable due to the multiple and not fully defined mechanisms of action vanadium compounds.

Crystal structures and supramolecular features of 9,9-dimethyl-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-tetraone, 3,7-diazaspiro[bicyclo[3.3.1]nonane-9,1′-cyclopentane]-2,4,6,8-tetraone and 9-methyl-9-phenyl-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-tetraone dimethylformamide monosolvate

Compounds (I), C9H10N2O4, (II), C11H12N2O4, and (III), C14H12N2O4·C3H7NO represent 9,9-disubstituted-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-tetraone derivatives with very similar molecular geometries for the bicyclic framework: the dihedral angle between the planes of the imide groups is 74.87 (6), 73.86 (3) and 74.83 (6)° in (I)–(III), respectively. The dimethyl derivative (I) is positioned on a crystallographic twofold axis and its overall geometry deviates only slightly from idealizedC2vsymmetry. The spiro-cyclopentane derivative (II) and the phenyl/methyl analog (III) retain only internalCssymmetry, which in the case of (II) coincides with crystallographic mirror symmetry. The cyclopentane moiety in (II) adopts an envelope conformation, with the spiro C atom deviating from the mean plane of the rest of the ring by 0.548 (2) Å. In compound (III), an N—H...O hydrogen bond is formed with the dimethylformamide solvent molecule. In the crystal, both (I) and (II) form similar zigzag hydrogen-bonded ribbons through double intermolecular N—H...O hydrogen bonds. However, whereas in (I) the ribbons are formed by twotrans-arranged O=C—N—H amide fragments, the amide fragments arecis-positioned in (II). The formation of ribbons in (III) is apparently disrupted by participation of one of its N—H groups in hydrogen bonding with the solvent molecule. As a result, the molecules of (III) form zigzag chains rather than the ribbons through intermolecular N—H...O hydrogen bonds. The crystal of (I) was a pseudo-merohedral twin.