title: Two new rare-class tetracyclic diterpenoids from Otostegia limbata.
abstract: Two new tetracyclic diterpenoids trivially named as limbatenolide D (1) and limbatenolide E (2) have been isolated from Otostegia limbata. The structure elucidation of the compounds was based primarily on two-dimensional (2D) NMR techniques and on comparison with the literature data.
authors.affiliation: International Center for Chemical and Biological Sciences, H.E.J. Research Institute of Chemistry, University of Karachi, Karachi, Pakistan.
authors.forename: Umar
authors.initials: U
authors.lastname: Farooq
authors.forename: Afsar
authors.initials: A
authors.lastname: Khan
authors.forename: Viqar Uddin
authors.initials: VU
authors.lastname: Ahmad
authors.forename: Saleha Suleman
authors.initials: SS
authors.lastname: Khan
authors.forename: Farzana
authors.initials: F
authors.lastname: Kousar
authors.forename: Saima
authors.initials: S
authors.lastname: Arshad
mesh_terms: D004224:Diterpenes / Q000737:chemistry* / Q000302:isolation & purification; D019686:Lamiaceae / Q000737:chemistry*; D015394:Molecular Structure
chemical_list: D004224:Diterpenes; C520696:limbatenolide D; C520697:limbatenolide E