title: Nine sesquiterpenes from Solanum torvum.
abstract: Three new sesquiterpenes, namely 3β,11-dihydroxy-4,14-oxideenantioeudesmane (1), 1β,10β,12,14-tetrahydroxy-allo-aromadendrane (2) and 1β,10β,13,14-tetrahydroxy-allo-aromadendrane (3), along with six known sesquiterpenes (4-9), were isolated from the roots of Solanum torvum. Compound 4 and 5 are epimers, their main difference lies in the C-11 configulation. Normally, epimers do not make a huge difference in C NMR spectra, but in this kind of structure of A, B, C rings, and C ring is sterically strained structure, stericall effects influence strongly the (13)C NMR chemical shifts, when C-11 configulation changed, it makes a huge difference in the three ring of structure, such as C-6, C-7, C-11. New compound 2 and 3 are epimers and similar to compound 4 and 5, their just increase a hydroxy in C-1 and have a same regular pattern in C NMR spectra, otherwise, compound 5 was firstly confirmed by single-crystal X-ray diffraction.
authors.affiliation: a Department of TCM Chemistry, School of Pharmacy , Shanghai University of Traditional Chinese Medicine , Shanghai , PR China.
authors.forename: Pulong
authors.initials: P
authors.lastname: Yuan
authors.affiliation: a Department of TCM Chemistry, School of Pharmacy , Shanghai University of Traditional Chinese Medicine , Shanghai , PR China.
authors.forename: Fujiang
authors.initials: F
authors.lastname: Guo
authors.affiliation: a Department of TCM Chemistry, School of Pharmacy , Shanghai University of Traditional Chinese Medicine , Shanghai , PR China.
authors.forename: Kaikai
authors.initials: K
authors.lastname: Zheng
authors.affiliation: a Department of TCM Chemistry, School of Pharmacy , Shanghai University of Traditional Chinese Medicine , Shanghai , PR China.
authors.forename: Kaixian
authors.initials: K
authors.lastname: Chen
authors.affiliation: a Department of TCM Chemistry, School of Pharmacy , Shanghai University of Traditional Chinese Medicine , Shanghai , PR China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Jia
authors.affiliation: a Department of TCM Chemistry, School of Pharmacy , Shanghai University of Traditional Chinese Medicine , Shanghai , PR China.
authors.forename: Yiming
authors.initials: Y
authors.lastname: Li
mesh_terms: D009682:Magnetic Resonance Spectroscopy; D018517:Plant Roots / Q000737:chemistry; D012717:Sesquiterpenes / Q000737:chemistry / Q000302:isolation & purification*; D032322:Solanum / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D012717:Sesquiterpenes
keywords: 13C NMR; Solanum torvum; epimers; sesquiterpenes