A class of monomeric nuphar analogues that are either epimeric at C1 and C1' or lack the naturally occurring methyl group at those positions were synthesized and evaluated for biological activity. The syntheses feature enantioselective vinylogous Mukaiyama-Mannich (vM-Mannich) reactions catalyzed by chiral phosphoric acids that proceed with excellent diastereoselectivity. Biological assays reve...

BACKGROUND The results presented herein show that the cyclic aminal (2S,7R,11S,16R)-1,8,10,17-tetraazapentacyclo[8.8.1.1.(8,17)0.(2,7)0(11,16)]icosane (6), derived from cis-(meso)-1,2-diaminocyclohexane and formaldehyde, is a suitable substrate for the preption of a series of cis-meso Mannich bases such as 8a-l by reaction with p-substituted phenols 7a-l in basic media. These compounds are valu...

Two consecutive measurements of the position of a non relativistic free particle will give entirely unrelated results. Recent quantum information research by G. Svetlichny, J. Tolar, and G. Chadzitaskos have explained this property of position observables as a result of a path in the Feynman integral being mathematically defined as a product of incompatible states; that is, as a product of mutu...

the direct three component modified mannich reaction via condensation of aldehydes, 2-naphthol or 2,7-naphthalendiol and piperidine to generate betti bases has been carried out over l-proline (20 mol%) with high efficiency under solvent free conditions at 70 oc. also, the reaction of aromatic aldehyde and 4-hydroxycoumarin in the presence of l-proline (20 mol%) in the ethanol under reflux condi...

The direct three component modified Mannich reaction via condensation of aldehydes, 2-naphthol or 2,7-naphthalendiol and piperidine to generate Betti bases has been carried out over L-proline (20 mol%) with high efficiency under solvent free conditions at 70 OC. Also, the reaction of aromatic aldehyde and 4-hydroxycoumarin in the presence of L-proline (20 mol%) in the ethanol under reflux condi...

Mannich bases were prepared from substituted phenols with aliphatic amines and formal­ dehyde. Amine exchange with N-methyl-2-naphthylamine followed by a Hofmann Martius rearrangement gave rise to o,o'-amino-hydroxy-diphenylmethane derivatives. Under cyclization conditions some of these compounds produced spirocyclohexadienones, which are the ipso analogs to the hypothetic intermediates postula...

Highly enantio- and diastereoselective organocatalytic Mannich reactions of glycine Schiff bases with N-Boc-protected imines are described. Imines were generated in situ from bench-stable alpha-amido sulfones. Catalysis mediated by a cinchona alkaloid thiourea provided optically active alpha,beta-diamino acid derivatives with up to 99% ee and near-perfect diastereoselection.