Related Experiment Video
Updated: Jun 8, 2025

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
Stereodivergent Synthesis of 6,12-Guaianolide C1 Epimers via a Rationally Designed Oxy-Cope/Ene Reaction Cascade
Kalliopi Mazaraki1, Christos Zangelidis1, Antonis Kelesidis1
1Laboratory of Organic Chemistry, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece.
Abstract:
Nature synthesizes epimeric C1 guaianolide congeners, key components of major natural product classes, through a single structurally flexible macrocyclic germacranolide core. Our rationally designed elemanolide-type scaffold (5) now mimics this natural process, enabling the stereodivergent synthesis of both C1 epimers of 6,12-guaianolide lactone motifs. An oxy-Cope/ene cascade acts as the key step of this process, generating two distinct conformers of an intermediate germacranolide, each leading to a specific C1 epimer. Highly stereoselective redox manipulations follow, culminating in the efficient syntheses of diverse osmitopsin-type guaianolides.
More Related Videos
10:17Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
07:12Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Related Concept Videos
[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement
Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
Preparation of Epoxides
Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of...
Sharpless Epoxidation
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction