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Tetrahydropyran Rings (tetrahydropyran + ring)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

Stereochemical Prins Cyclization: Electronic versus Steric Effects on the Synthesis of 2,4,6-Trisubstituted Tetrahydropyran Rings.

CHEMINFORM, Issue 15 2007
Kok-Ping Chan
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source]

Tetrahydropyran Rings from a Mukaiyama,Michael Cascade Reaction.

CHEMINFORM, Issue 12 2006
Megan L. Bolla
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source]

ChemInform Abstract: Stereoselective Synthesis of Substituted Tetrahydropyran Rings via 6-exo and 6-endo Selenoetherification.

CHEMINFORM, Issue 24 2002
Carmela Aprile
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

Total Synthesis of Potent Antitumor Agent (,)-Lasonolide,A: A Cycloaddition-Based Strategy

CHEMISTRY - AN ASIAN JOURNAL, Issue 10 2008

Abstract A detailed account of the enantioselective total synthesis of (,)-lasonolide,A is described. Our initial synthetic route to the top tetrahydropyran ring involved Evans asymmetric alkylation as the key step. Initially, we relied on the diastereoselective alkylation of an ,-alkoxyacetimide derivative containing an ,, stereogenic center and investigated such an asymmetric alkylation reaction. Although alkylation proceeded in good yield, the lack of diastereoselectivity prompted us to explore alternative routes. Our subsequent successful synthetic strategies involved highly diastereoselective cycloaddition routes to both tetrahydropyran rings of lasonolide,A. The top tetrahydropyran ring was constructed stereoselectively by an intramolecular 1,3-dipolar cycloaddition reaction. The overall process constructed a bicyclic isoxazoline, which was later unravelled to a functionalized tetrahydropyran ring as well as a quaternary stereocenter present in the molecule. The lower tetrahydropyran ring was assembled by a Jacobsen catalytic asymmetric hetero-Diels,Alder reaction as the key step. The synthesis also features a Lewis acid catalyzed epoxide opening to form a substituted ether stereoselectively. [source]