Mass spectra of germacranolide type sesquiterpene dilactones and derivatives

Abstract
The low and high resolution mass spectra of five germacranolide sesquiterpene dilactones together with the d0‐, d3‐acetates, d0‐, d9‐TMSi derivatives and deuterium exchange products were obtained. The mass spectra of the five dilactones revealed several kinds of common fragment ions. The germacranolides containing a 4,5 double bond exhibit characteristic ions at m/e 274, 256, 228, 165 and 147, while the 4,5‐dihydro compound exhibits fragment ions at m/e 276, 258, 230 and 162.