Asymmetric synthesis of 3,5-disubstituted indolizidines by intermolecular addition of an allylsilane on an N-acyliminium ion.

A diastereoselective synthesis of 3,5-disubstituted indolizidines based on an intermolecular addition of an allylsilane on an acyliminium ion derived from (S)-pyroglutamic acid is described. The synthetic potential of this methodology is demonstrated by the enantioselective synthesis of (−)-indolizidine 195B, (−)-indolizidine 223AB, (+)-monomorine and (−)-3-butyl-5-propyl indolizidin

Efficient synthesis of 3-hydroxymethylated cis- and trans- cyclobutane b-amino acids using an intramolecular photocycloaddition strategy

Uracil bearing a tethered allyl alcohol appendage at N1 undergoes a [2+2] photocycloaddition reaction to provide a single tricyclic adduct in high yield. This compound is transformed in one step into a cis-cyclobutane β-amino acid bearing a 3-hydroxymethyl group. Through appropriate functionalization and epimerization, the trans isomer is obtained therefrom in only three further steps

A convenient allylsilane-N-acyliminium route toward indolizidine and quinolizidine alkaloids

This review relates all the results that we obtained in the field of the total synthesis of indolizidine and quinolizidine alkaloids using a strategy of the addition of an allylsilane on an N-acyliminium ion. In this paper, we describe the synthesis of racemic indolizidine 167B and chiral indolizidines: (-)-indolizidines 167B, 195B, 223AB, (+)-monomorine, (-)-(3R,5S,8aS)-3-butyl-5-propylindolizidine and (-)-dendroprimine. Next, we relate the synthesis that we have developed in the quinolizidines field: (±)-myrtine and epimyrtine, (±)-lasubines I and II and chiral quinolizidines: (+)-myrtine, (-)-epimyrtine, (-)-lasubines I and II and (+)-subcosine II

Bêta-aminoallylsilanes chiraux, nouveaux synthons pour la préparation de pipéridines substituées (Synthèse totale du(+)-alcaloïde 241 D et de la (+)-isosolénopsine A(HCl))

CLERMONT FD-BCIU Sci.et Tech. (630142101) / SudocSudocFranceF

A convenient access to the piperidine ring by cyclization of allylsilyl substituted N-acyliminium and iminium ions : application to the synthesis of piperidine alkaloids

International audienc

Synthèse stéréosélective de pipéridines 2,6-disubstitutées

Poste

Synthèse stéréosélective de pipéridines 2,6-disubstituées

Communication oral

Edifices glycoconjugués multivalents beta-peptides-antigène Tn.

Poste