1333041-91-0Relevant academic research and scientific papers
Stereodivergent synthesis of the C1-C9 tetrahydropyran subunit of zincophorin and isomers thereof
Godin, Franois,Katsoulis, Ioannis,Fiola-Masson, Emilie,Dhambri, Sabrina,Mochirian, Philippe,Guindon, Yvan
, p. 474 - 488 (2012/03/11)
Zincophorin C1-C9 fragment and seven tetrahydropyran analogues were prepared diastereoselectively by sequential iodoetherification and radical hydrogen-transfer reactions. Stereoselective formation of 3,7-trans or 3,7-cis rings was rationalized through minimization of allylic-1,3 strain in chair-like transition states. Subsequent hydrogen-transfer provided 7,8-anti or 7,8-syn isomers under acyclic stereocontrol or endocyclic control respectively. The latter approach relies on the formation of a [4.4.0] bicyclic complexes resulting from the chelation of the oxygen of the tetrahydropyran ring and the ester by a bidentate Lewis acid. Georg Thieme Verlag Stuttgart New York.
A bidirectional approach to the synthesis of polypropionates: Synthesis of C1-C13 fragment of zincophorin and related isomers
Mochirian, Philippe,Godin, Francois,Katsoulis, Ioannis,Fontaine, Isabelle,Brazeau, Jean-Francois,Guindon, Yvan
experimental part, p. 7654 - 7676 (2011/12/14)
The structure-activity study of a bioactive natural product containing polypropionate subunits requires that its stereoisomers also be evaluated. Therefore, a general approach to synthesize these motifs is necessary. We describe herein the synthesis of the C1 - C13 polypropionate subunit of zincophorin and isomers there of using a two-reaction sequence: an aldol reaction using a mixture of tetrasubstituted enoxysilanes and a hydrogen-transfer reaction, both under Lewis acid control. Selection of the appropriate Lewis acid dictates the stereochemical outcome of these reactions. From a tactical standpoint, this study shows how a polypropionate sequence can be read and constructed in two directions, either the east-west or the west-east approaches. The choice of the optimal route is influenced by the number of complexation sites that can interfere in the aldol step under bidentate Lewis acid control.
