Mireille Attolini

Enantioselective synthesis of cyclic dialkyl (3-hydroxy-1-alkenyl) phosphonates by baker's yeast-mediated reduction of the corresponding enones

Abstract Cyclic dialkyl (3-oxo-1-cycloalkenyl) phosphonates were subjected to bakers yeast-mediated enantioselective reductions to afford the corresponding dialkyl (3-hydroxy-1-alkenyl) phosphonates. The six- and seven-membered ring enones were reduced with moderate to good enantiomeric excesses, whereas the five-membered ring substrate always yielded the double bond reduced compound. The use of different reduction conditions did not improve the ees markedly, but it was found, for the six-membered analogues, that the alkyl groups held by phosphorus influence dramatically the enantioselectivity of the reduction, leading to up to 95% enantiomeric excess.

Design, synthesis and biological evaluation of a bivalent μ opiate and adenosine A1 receptor antagonist

The cross talk between different membrane receptors is the source of increasing research. We designed and synthesized a new hetero-bivalent ligand that has antagonist properties on both A(1) adenosine and mu opiate receptors with a K(i) of 0.8+/-0.05 and 0.7+/-0.03 microM, respectively. This hybrid molecule increases cAMP production in cells that over express the mu receptor as well as those over expressing the A(1) adenosine receptor and reverses the antalgic effects of mu and A(1) adenosine receptor agonists in animals.

Expeditious synthesis and biological evaluation of new C-6 1,2,3-triazole adenosine derivatives A1 receptor antagonists or agonists

The synthesis of new C-6 1,2,3-triazole adenosine derivatives via microwave assisted 1,3-dipolar cycloaddition as key step is described. The binding on membranes of cells that over express A(1) adenosine receptors (A(1)AR) was also evaluated. Among them, four compounds increased cAMP production, in a dose-dependent manner acting as antagonists of the A(1)AR, while two compounds act as agonists.

Enzymatic resolution of diethyl (3-hydroxy-1-butenyl) phosphonate

The enzymatic esterification of diethyl (3-hydroxy-1-butenyl) phosphonate 1 with different enzymes has been carried out, and allows the preparation of (S)-1 and (R)-diethyl (3-acetoxy-1-butenyl) phosphonate 2 with very high enantiomeric excess. The absolute conguration of 1 was determined by independent synthesis from (S)-ethyl lactate.

Palladium-Catalyzed Acetoxylation of Cyclic Allyl Phosphonates in the Presence of Isopentyl Nitrite and Using Molecular Oxygen as Final Oxidant

Abstract The palladium-catalyzed acetoxylation of cyclic dialkyl allyl phosphonates is effected using palladium chloride as catalyst, in the presence of isopentyl nitrite in acetic acid under an oxygen atmosphere. The proposed mechanism for the reaction involves a palladium nitro–nitroso redox couple.

A DIASTEREOSELECTIVE PALLADIUM-CATALYZED ACETOXYLATION OF RACEMIC ALLYL PHOSPHORUS COMPOUNDS

Abstract The palladium-catalyzed acetoxylation of chiral racemic allyl phosphorus compounds 1 and 2 occurs diastereoselectively, showing that the presence of a chiral moiety on phosphorus can influence the stereochemical course of the reaction. Although the yield obtained from 1 is very low, the use of 2 leads to a 50% diastereomeric excess and 86% yield.