Abstract
Ellagitannins are a structurally and biologically diverse class of hydrolysable tannins. The structure typically consists of galloyl and hexahydroxydiphenoyl group(s), which are esterified to glucose. A number of biological and pharmacological activities have been reported in this class of natural products. The focus of this review is progress in strategies and methodologies for the total synthesis of ellagitannins. The first half of this review describes the previously achieved total syntheses along with the synthetic problems and solutions including formation of the HHDP-bridge, preparation of dehydrodigalloyl ether, control of anomeric isomers, and protecting groups in the syntheses. The latter half describes the three recent total syntheses of ellagitannins including details of the first synthesis of an axial- rich ellagitannin, of which glucose moiety is in a 1C4 or a twist-boat conformation that has more axially oriented C-O bonds.
Keywords: Ellagitannin, Total synthesis, Synthetic strategy and methodology, Axial-rich
Call for Papers in Thematic Issues
Catalytic C-H bond activation as a tool for functionalization of heterocycles
The major topic is the functionalization of heterocycles through catalyzed C-H bond activation. The strategies based on C-H activation not only provide straightforward formation of C-C or C-X bonds but, more importantly, allow for the avoidance of pre-functionalization of one or two of the cross-coupling partners. The beneficial impact of ...read more
Related Books
Advances in Organic Synthesis
The Synthetic Methods, Structures, and Properties of the Ca-C σ Bond Organocalcium Containing Compounds
Advances in Organic Synthesis
Chemistry of Bipyrazoles: Synthesis and Applications
Advances in Organic Synthesis
Advanced Nanocatalysis for Organic Synthesis and Electroanalysis
Advances in Organic Synthesis
Advances in Organic Synthesis
19