Stereocontrolled synthesis of trans-eudesmanolides from (+)-hanphilline

Abstract

Directed synthesis methods of practically significant eudesmanolides on the basis of germacranolide E,E-hanphilline were presented in this article. Synthesis of obtained trans-eudesmanolides was carried out with stereocontrolled 5,10-cyclization of E,E-germaсranolide (+)-hanphilline. The considered mechanism of 5,10-carbocyclization of the E,E-germaсranolide (+)-hanphilline consistent with the results of quantumchemical calculations of the total energies of all cationic intermediates formed during the reaction. It was shown that electrophilic reagents led to different eudesmanolide sesquiterpenoids. The one-step synthetic method of functionalized at С-1 and С-3 trans-eudesmanolides was developed.