Total synthesis of the proposed structure of decurrenside D

Nucleophilic substitution at the anomeric position of furanose carbohydrates. The case of the C-allylations

Taking advantage of the locked conformation of cyclic furanose form, carbohydrate derivatives have been transformed into relevant tetrahydrofuran moieties through a chemical operation commonly known as C-glycosylation reaction. Consequently, a large number of total synthesis of naturally occurring products containing this heterocycle have been accomplished by applying this reaction. In this regard, the C-allylation reaction of furanose carbohydrates provides flexible routes for stereoselective anomeric functionalization by incorporating an allyl group, which is eventually re-functionalized into advanced natural product intermediates. Therefore, this mini review deals with the description of the origin of the stereoselectivity and synthetic applications of this type of glycosylation reaction, which can be also called as: "Nucleophilic Substitution at the Anomeric Position", conducted by various research groups including our own group.

Recent trends in the structural revision of natural products

Covering: 2012 to 2017 This article reviews recent reports on the structural revision of natural products. Through a critical assessment of the original and revised published structures, the article addresses why each structure was targeted for revision, discusses the techniques and key discrepancies that led to the proposal of the revised structure, and offers measures that may have been taken during the original structure determination to prevent error. With the revised structures in hand, weaknesses of original proposals are assessed, providing a better understanding on the logic behind structure determination.