title: Constituents of Senecio chionophilus with potential antitubercular activity.
abstract: Two new sesquiterpenoids, (1S,4S,5R,10R)-1-hydroxy-6-isobutyryloxy-10H-9-oxofuranoeremophilane (1) and 1alpha-hydroxy-6beta-(2xi-methylbutyryloxy)-10alphaH-9-oxofuranoeremophilane (2), along with 21 known constituents, were isolated from the n-hexane and dichloromethane extracts of the above-ground biomass and roots of Senecio chionophilus. The structures of 1 and 2 were elucidated on the basis of spectroscopic evidence and chemical transformation methods. The absolute configuration of 1 was determined by Mosher ester methodology. All of the isolates were evaluated for their antitubercular potential against Mycobacterium tuberculosis in a microplate Alamar Blue assay. Compound 2, 6beta-angeloyloxy-1alpha-hydroxy-10alphaH-9-oxofuranoeremophilane (3), and 4'-hydroxyacetophenone (6) exhibited mild antitubercular activity at minimum inhibitory concentrations of 119, 114, and 121 microg/mL, respectively.
authors.affiliation: Department of Pharmacology and Toxicology, Division of Medicinal and Natural Products Chemistry, College of Pharmacy, University of Arizona, Tucson, Arizona 85721, USA.
authors.forename: Jian-Qiao
authors.initials: JQ
authors.lastname: Gu
authors.forename: Yuehong
authors.initials: Y
authors.lastname: Wang
authors.forename: Scott G
authors.initials: SG
authors.lastname: Franzblau
authors.forename: Gloria
authors.initials: G
authors.lastname: Montenegro
authors.forename: Barbara N
authors.initials: BN
authors.lastname: Timmermann
mesh_terms: D000995:Antitubercular Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002677:Chile; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D009169:Mycobacterium tuberculosis / Q000187:drug effects*; D019906:Nuclear Magnetic Resonance, Biomolecular; D018517:Plant Roots / Q000737:chemistry; D010947:Plants, Toxic / Q000737:chemistry*; D012674:Senecio / Q000737:chemistry*; D012717:Sesquiterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D013237:Stereoisomerism
chemical_list: C493072:(1S,4S,5R,10R)-1-hydroxy-6-isobutyryloxy-10H-9-oxofuranoeremophilane; C493073:1alpha-hydroxy-6beta-(2xi-methylbutyryloxy)-10alphaH-9-oxofuranoeremophilane; D000995:Antitubercular Agents; D012717:Sesquiterpenes