title: Antitumor agents 37. The isolation and structural elucidation of isohelenol, a new antileukemic sesquiterpene lactone, and isohelenalin from Helenium microcephalum.
abstract: The known compound isohelenalin (1) was isolated from Helenium microcephalum and the previously reported structure confirmed on the basis of physicochemical data and chemical transformation. In addition, a new antileukemic sesquiterpene lactone, isohelenol (2), was isolated and its structure elucidated.
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000302:isolation & purification*; D055598:Chemical Phenomena; D002621:Chemistry; D007783:Lactones / Q000302:isolation & purification; D007938:Leukemia / Q000188:drug therapy; D010946:Plants, Medicinal / Q000032:analysis*; D012717:Sesquiterpenes / Q000302:isolation & purification*; D013237:Stereoisomerism
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D007783:Lactones; D012717:Sesquiterpenes