Total synthesis of the marine macrolide (+)-neopeltolide.

A concise total synthesis of the antiproliferative macrolide (+)-neopeltolide has been completed, utilising a Jacobsen hetero Diels-Alder reaction to install the trisubstituted tetrahydropyran ring.

Formal total synthesis of triptolide.

A new approach to the medicinally-important natural product triptolide is significantly shorter than previous syntheses, highly convergent and avoids the use of protecting groups; key features include two Diels-Alder reactions and a new deoxygenative aromatisation process.

Enhanced stereocontrol in Diels-Alder reactions of chiral dienols.

This combined experimental-computational investigation demonstrates that the presence of a removable bromine substituent on a diene leads to complete pi-diastereofacial and endo/exo stereoselection in both intermolecular and intramolecular Diels-Alder reactions. The influence of the bromine upon stereoselectivity is dramatic: the cycloaddition of nonbrominated precursor 18E, for example, gives four diastereomeric products in a 55:13:16:16 ratio; the bromine-containing analogue gives one stereoisomer within the limits of detection. The examination of B3LYP/6-31+G(d) transition structures allows an interpretation of these experimental findings.

Allylic stereocontrol of the intramolecular Diels-Alder reaction.

The stereochemical outcome of the intramolecular Diels-Alder reaction of ester-linked 1,3,8-nonatrienes can be controlled by substituents about a stereogenic center attached to C1. The scope and limitations of this approach have been investigated, with variation in substrate structure about the allylic stereocenter and the dienophile. The stereochemical outcomes of these reactions are explained by reference to B3 LYP/6-31G(d) transition structures.