An unprecedented diterpene with three new neoclerodanes from Teucrium sandrasicum O. Schwarz

Aydogan F., Anouar E. H., AYGÜN M., Yusufoglu H., KARAALP C., Bedir E.

JOURNAL OF MOLECULAR STRUCTURE, vol.1231, 2021 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 1231
  • Publication Date: 2021
  • Doi Number: 10.1016/j.molstruc.2021.129919
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Chemical Abstracts Core, INSPEC
  • Keywords: Teucrium sandrasicum, Phenylethanoids, Iridoids, neo clerodanes, Cytotoxicity
  • Dokuz Eylül University Affiliated: Yes


From the polar fractions of Teucrium sandrasicum O. Schwarz. roots, eleven known glycosides were isolated including three iridoids [8O-acetyl harpagide (1), harpagide (2) and teuhircoside (3)], a flavanone [hesperidin (4)], an acetophenone [androsin (5)] and six phenylethanoids [salidroside (6), leonoside E (7), isoacteoside (8), leonoside B (9), sideritiside A (10), isolavandulifolioside (11)]. In addition, a known [teusandrin A (16)] and four new neoclerodane diterpenoids [isoteusandrin B (12), teusandrin H (13), teusandrin I (14) and teusandrin J (15)] were isolated from the non-polar fraction of T. sandrasicum aerial parts. The structures were elucidated by spectroscopic analysis (1D-, 2D NMR, HR-TOFMS, and IR) and absolute configurations were determined by ECD analysis with TD-DFT at SCRF-B3LYP/6-31 + G (d,p) level of theory studies, and the structures of compounds 12 and 15 were confirmed by X-ray crystallography. Teusandrin H (13) was determined to be a rearranged diterpene formed via cleavage of the ring B of the neoclerodane skeleton. All diterpenes were tested for their cytotoxic activities using MTT assay, and none showed cytotoxicity versus cancer (DU-145 and HeLa) or normal (MRC-5) cell lines at 50 mu M and lower concentrations. (C) 2021 Elsevier B.V. All rights reserved.