1 is due to a carbonyl group which is not in conjugation with the lactone an electron ionization ei mass spectrum fig3 of gomphostinin is acquired using a finnigan mat mass spectrometer the ei mass spectra of gomphostenin gave an m ion at m z 332 and fragment ions at m z 317 299 287 222 221 191 175 161 150 147 and 135 fig4 electro spray ionization mass esi ms spectrometry is carried out using a quadrapole time of flight q tof micro mass spectrometer of micromass the compound is injected to the mass spectrometer using waters hplc system and esi is used as ionization mode esi ms spectrum of gomphostinin gave an m h ion at m z 333 fig5 the high resolution mass hrms measurement fig6 of ion at 333 da is carried out by q tof micro mass spectrometer using lock spray reference mass sulfadimethoxine 311 0814 da keeping collision energy at 25 v sample cone voltage at 40v argon as collision gas the measured exact mass 333 2053 corresponds to an empirical formula c 20 h 28 o 4 with an error of 1 3 mda units the proton nmr spectrum fig7 of gomphostenin gave resonances corresponding to 28 protons the spectrum contains signals due to three methyl groups at 0 80 1 05 and 1 89.