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Synthèse totale énantiosélective de la (11R)-(-)-8-épi-11-hydroxy-aphidicoline par réactions de Diels-Alder/aldol transannulaires en tandem
(Université de Sherbrooke, 1999)
Au cours de cette thèse, nous verrons la synthèse totale de la (11R )-(-)-8-épi-11-hydroxy-aphidicoline et toutes les recherches pour y arriver. Le présent ouvrage sera divisé en quatre grandes parties. Dans un premier ...
Effect of substitution on the intramolecular 1,3-dipolar cycloaddition of alkene tethered münchnones
(2007)
Abstract: A sequence of chemoselective activation of N-acylaminoacids, münchnone generation, intramolecular 1,3-dipolar cycloaddition, and ring opening efficiently generated functionalized polycyclic structures such as ...
Synthesis of the tricyclic core of alkaloid securinol B using a cascade of vilsmeier-haack and mannich cyclizations
(2008)
Abstract: The Securinega alkaloids are a family of approximately 20 tetracyclic compounds isolated from diverse Securinega, Phyllanthus, and Margaritaria species of the Euphorbiaceae plant family. Most of these alkaloids ...
Studies toward total synthesis of (±)-caldaphnidine C via one-pot sequential intramolecular Vilsmeier–Haack and azomethine ylide 1,3-dipolar cycloaddition
(2016)
An application of a one-pot sequential Vilsmeier–Haack cyclization and intramolecular azomethine ylide 1,3-dipolar cycloaddition toward the total synthesis of (±)-caldaphnidine C is presented. It allowed an efficient ...
Preparation of conformationally restricted β2,2- and β2,2,3-amino esters and derivatives containing an all-carbon quaternary center
(2015)
Abstract: β-Amino acids are routinely incorporated into peptidic drugs to increase their stability and to incur conformational biases. However, the synthesis of highly substituted β-amino acids still represents a great ...
Highly diastereoselective synthesis of substituted pyrrolidines using a sequence of azomethine ylide cycloaddition and nucleophilic cyclization
(2010)
Abstract: Although cycloadditions of azomethine ylides usually give mixtures of endo/exo adducts, we successfully tuned the mechanistic path of a new reaction cascade to afford substituted pyrrolidines in high yields and ...
A Versatile cascade of intramolecular vilsmeier-haack and azomethine ylide 1,3-dipolar cycloaddition toward tricyclic cores of alkaloids
(2008)
Abstract: In the pursuit of synthetic efficiency, we developed an innovative one-pot transformation of linear substrates into bi- and tricyclic adducts using a
cascade of amide activation, nucleophilic cyclization, ...
Synthesis of the tetracyclic core of daphnilactone B-type and yuzurimine-type alkaloid
(2011)
Abstract: The core of daphnilactone B-type and yuzurimine-type alkaloids was synthesized in only 16 steps from a known β-allyl-γ-butyrolactone. The key sequence of Vilsmeier–Haack cyclization and intramolecular azomethine ...
Asymmetric total synthesis of (+)-virosine a via sequential nucleophilic cyclizations onto an activated formamide
(2012)
Abstract: The first synthesis of tetracyclic alkaloid virosine A is reported. The natural alkaloid was prepared in only 13 steps, in an enantioenriched form. The azabicyclo[2.2.2]octane core was efficiently assembled using ...
Intramolecular additions of various π-nucleophiles to chemoselectively activated amides and application to the synthesis of (±)-tashiromine
(2006)
Abstract: Vilsmeier-Haack type cyclizations proved to be particularly efficient for generating parts of the polycyclic
cores of many alkaloids, although only monocyclizations have so far been reported. With the goal ...