Ring-Contraction vs Ring-Expansion Reactions of Spiro-cyclopropanecarboxylated Sugars
摘要:
Electrophilic ring opening of spiro-cyclopropanecarboxylated sugars followed by reaction with DBU revealed interesting ring-contraction and ring-expansion reactions depending on the substrate and the kind of hydroxyl protective group present adjacent to the Spiro center. A stereoselective method for accessing a new class of carbon chain extended keto-furanoses and C-glycosylated bicyclic compounds is reported.
Ring-Contraction vs Ring-Expansion Reactions of Spiro-cyclopropanecarboxylated Sugars
摘要:
Electrophilic ring opening of spiro-cyclopropanecarboxylated sugars followed by reaction with DBU revealed interesting ring-contraction and ring-expansion reactions depending on the substrate and the kind of hydroxyl protective group present adjacent to the Spiro center. A stereoselective method for accessing a new class of carbon chain extended keto-furanoses and C-glycosylated bicyclic compounds is reported.
Stereoselective synthesis of 1,6-dioxaspirolactones from spiro-cyclopropanecarboxylated sugars: total synthesis of dihydro-pyrenolide D
作者:Bandi Ramakrishna、Perali Ramu Sridhar
DOI:10.1039/c4ra16753h
日期:——
efficient method for the stereoselective construction of 1,6-dioxaspiro[4.n]decan-2-one systems (n = 4, 5) fromsugar derived spirocyclopropane carboxylic acids involving a one-pot ring-opening and cyclization reaction is revealed. The generality of the methodology and its application in the totalsynthesis of dihydro-pyrenolide D and 4-epi-dihydro-pyrenolide D are reported.
Ring-Contraction vs Ring-Expansion Reactions of Spiro-cyclopropanecarboxylated Sugars
作者:Bandi Ramakrishna、Perali Ramu Sridhar
DOI:10.1021/ol402021e
日期:2013.9.6
Electrophilic ring opening of spiro-cyclopropanecarboxylated sugars followed by reaction with DBU revealed interesting ring-contraction and ring-expansion reactions depending on the substrate and the kind of hydroxyl protective group present adjacent to the Spiro center. A stereoselective method for accessing a new class of carbon chain extended keto-furanoses and C-glycosylated bicyclic compounds is reported.