mannich-bases and quinone

An efficient catalytic enantioselective direct Mannich reaction of glycinate Schiff bases with aryl imines leading to anticonfigured orthogonally protected alpha,beta-diaminoesters has been realized. Keys to success in this new catalyst system are the use of Fesulphos/Cu(CH3CN)4PF6 (3-5 mol%) as a Lewis acid catalyst and readily available N-(8-quinolyl)sulfonyl-protected aldimines as substrates, affording excellent levels of diastereo- (typically anti/syn > 90:10) and enantiocontrol (typically > or = 90% ee). A remarkable feature of this catalyst system is that it allows the construction of products with a tetrasubstituted carbon stereocenter at C-alpha in a highly diastereo- and enantiocontrolled manner.

Topics: Amines; Benzoquinones; Catalysis; Esters; Glycine; Imines; Mannich Bases; Molecular Structure; Schiff Bases; Stereoisomerism; Sulfones

A series of 2-[[4-(substituted-phenyl/ benzyl)-1-piperazinyllmethyl]-6-(4-methoxyphenyl)-3(2H)pyridazinone derivatives was prepared and examined for analgesic and anti-inflammatory activities. The structures of these new pyridazinone derivatives were confirmed by their IR and 1H-NMR spectra and elementary analysis. Among the compounds prepared, 2-[[4-(4-fluorophenyl)-1-piperazinyl]methyl]-6-(4-methoxyphenyl)-3(2H)pyridazinone IVe was found to be a most promising analgesic and anti-inflammatory agent. Compound IVe showed more potent analgesic activity than acetylsalicyclic acid in the phenylbenzoquinone-induced writhing test. Also IVe showed anti-inflammatory activity comparable to that of the standard compound indometacin against the carrageenan-induced paw edema. Side effects of the compounds were examined on gastric mucosa. None of the compounds showed a gastric ulcerogenic effect compared with reference nonsteroidal anti-inflammatory drugs. On the basis of the available data, the structure-activity relationship of the series of 2-[[4-(substituted-phenyl/benzyl)-1-piperazinyl]methyl]-6-(4-methoxyphenyl)-3(2H) pyridazinones is also discussed.

Topics: Analgesics; Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzoquinones; Edema; Foot; Indicators and Reagents; Magnetic Resonance Spectroscopy; Male; Mannich Bases; Mice; Muscle Contraction; Pyridazines; Solvents; Spectrophotometry, Infrared; Stomach Ulcer; Structure-Activity Relationship