title: Antitumor agents XXVIII: Structural elucidation of the novel antitumor sesquiterpene lactone, microlenin, from Helenium microcephalum.
mesh_terms: D000972:Antineoplastic Agents, Phytogenic; D055598:Chemical Phenomena; D002621:Chemistry; D007783:Lactones; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008968:Molecular Conformation; D012717:Sesquiterpenes
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D007783:Lactones; D012717:Sesquiterpenes; C017538:microlenin