74220-50-1

A ruthenium-grafted hydrotalcite (Ru/HT) and hydrotalcite-supported palladium nanoparticles (Pdnano/ HT) are easily prepared by treating basic layered double hydroxide, hydrotalcite (HT, Mg6Al 2(OH)16CO3) with aqueous RuCl 3·n H2O and K2[PdCl4] solutions, respectively, using surface impregnation methods. Analysis by means of X-ray diffraction, and energydispersive X-ray, electron paramagnetic resonance, and X-ray absorption fine structure spectroscopies proves that a monomeric RuIV species is grafted onto the surface of the HT. Meanwhile, after reduction of a surface-isolated PdII species, highly dispersed Pd nanoclusters with a mean diameter of about 70 A is observed on the Pdnano/HT surface by transmission electron microscopy analysis. These hydrotalcite-supported metal catalysts can effectively promote α-alkylation reactions of various nitriles with primary alcohols or carbonyl compounds through tandem reactions consisting of metal-catalyzed oxidation and reduction, and an aldol reaction promoted by the base sites of the HT. In these catalytic α-alkylations, homogeneous bases are unnecessary and the only by-product is water. Additionally, these catalyst systems are applicable to one-pot syntheses of glutaronitrile derivatives.

Treatment of a hydrotacite, Mg6Al2(OH)16CO3, with an aqueous solution of RuCl3·nH2O afforded a monomeric Ru(IV) species on the surface of the hydrotalcite. This novel Ru-grafted hydrotalcite (Ru/HT) efficiently catalyzed α-alkylation of nitriles with primary alcohols through the cooperative catalysis between the Ru species and the surface base sites. The catalyst system could be further extended for the one-pot synthesis of α,α-dialkylated phenylacetonitriles via the base-catalyzed Michael reaction of α-alkylated phenylacetonitrile with activate olefins. Copyright

The synthesis and biological evaluation of 3-alkyl-substituted 3-(4-aminophenyl)piperidine-2,6-diones as inhibitors of estrogen biosynthesis are described .In vitro compounds 4-14 showed a stronger inhibition of human placental aromatase compared to aminoglutethimide (AG, compound 3), which recently has become used for the treatment of hormone-dependent breast cancer.The most active derivative, compound 10, showed a 93-fold stronger inhibition than AG.With the exception of 5, 7, and 8, all other compounds exhibited similar or decreased inhibition of bovine adrenal desmolase compared to AG.Compounds 4 and 6-12 showed a stronger inhibition of the plasma estradiol concentration of pregnant mare serum gonadotropin (PMSG) primed Sprague-Dawley (SD) rats compared to the parent compound.Compounds 4, 6-8, 10, and 12 inhibited the testosterone-stimulated tumor growth of ovariectomized 9,10-dimethyl-1,2-benzanthracene (DMBA) tumor-bearing SD rats more strongly than AG.Being stronger and more selective inhibitors of the estrogen biosynthesis than AG, some of the newly developed derivatives of AG might be better candidates for the treatment of the hormone-dependent human breast cancer.