THE STRUCTURE OF VERSICOLACTONE A FROM ARISTOLOCHIA VERSICOLAR S.M. HWANG

A novel sesquiterpene lactone, versicolactone A, with 12-carbon ring skeleton, was isolated from the roots of Aristolochia versicolar S. M. Hwang. Versicolactone A, C₁₅H₂₀O2, colorless prisms, mp 130～132℃, α_D⁶ +486°(c 0.1276,CHC₁₃). Its structure was established by spectroscopic methods, mainly 2D-NMR (¹H-¹H COSY, ¹H-¹³C COSY, COLOC), HRMS and metastable ion measurement.