New sesquiterpene esters from Euonymus verrucosus: the ‘Ever’ series. X-Ray molecular structure of Ever-1
Seven new sesquiterpenoid esters (Ever-1, -2, -4, -6, -7, -8, and -10) have been isolated from Euonymus verrucosus. Structure (3) was determined for Ever-1 by X-ray (direct methods) analysis: the structure incorporates the pentahydroxydihydroagarofuran 3,4-dideoxymaytol. The same core is found in Ever-4, Ever-8, and Ever-10. However, Ever-2, -6, and 7 are esters of the hexahydroxydihydroagarofuran, 3,4,12-trideoxyeuonyminol (alatol).