title: Diterpene Foliar exudates of Blakiella bartsiifolia and phytotoxicity of clerodanes.
abstract: Blakiella bartsiifolia (S.F. Blake), an endemic and rare high altitude plant of the northern Andes, appears well adapted to the prevailing harsh environment owing in part to a thick glandular trichome cover. From foliar exudates, two new clerodanes, 15,16-epoxy-2-hydroxy-3,13(16),14-clerodatrien-20-oic acid (bartsiifolic acid) (2) and Z-15,16-dihydroxy-3,13-clerodien-20-oic acid (barthydrolic acid) (3), were isolated in addition to the known junceic acid (1). In addition, three new alicyclic furanoditerpenes: 1,20-epoxy-1,3(20),6(E),10(E),14-phytapentaen-18-methyl-19-oic acid (blakielic acid) (4), 1,20-epoxy- 1,3(20),10(E),14-phytapentaen-18-methyl-19-oic acid (blakifolic acid) (5) and 1,20-epoxy-1,3(20),6,14-phytatetraen-19-methyl-18-oic acid (dihydrocentipedic acid) (6) were obtained in minor quantity. Seed germination and plantlet growth bioassays on Allium cepa and Lactuca sativa to monitor bioactivity during isolation procedures revealed compounds 1-3 with substantial inhibition comparable with synthetic linuron.
authors.forename: Diego
authors.initials: D
authors.lastname: Rodriguez-Hernandez
authors.forename: Alberto
authors.initials: A
authors.lastname: Oliveros-Bastidas
authors.forename: Miguel E
authors.initials: ME
authors.lastname: Alonso-Amelot
authors.forename: Maria Pia
authors.initials: MP
authors.lastname: Calcagno-Pissarelli
mesh_terms: D000490:Allium / Q000187:drug effects; D019659:Asteraceae / Q000737:chemistry*; D004224:Diterpenes / Q000737:chemistry / Q000494:pharmacology; D045785:Diterpenes, Clerodane / Q000737:chemistry* / Q000494:pharmacology*; D018525:Germination / Q000187:drug effects; D018545:Lactuca / Q000187:drug effects; D015394:Molecular Structure; D053147:Plant Exudates / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D004224:Diterpenes; D045785:Diterpenes, Clerodane; D053147:Plant Exudates