| Autor: |
Hussien TA; Pharmacognosy Department, Faculty of Pharmacy, Sphinx University, New Assiut City, Assiut 10, Egypt., Mohamed TA; National Research Centre, Chemistry of Medicinal Plants Department, 33 El-Bohouth St., Dokki, Giza 12622, Egypt., Elshamy AI; National Research Centre, Department of Natural Compounds Chemistry, 33 El-Bohouth St., Dokki, Giza 12622, Egypt., Moustafa MF; Department of Biology, College of Science, King Khalid University, Abha 61421, Saudi Arabia.; Department of Botany & Microbiology, Faculty of Science, South Valley University, Qena 83523, Egypt., El-Seedi HR; Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, S-106 91 Stockholm, Sweden.; International Research Center for Food Nutrition and Safety, Jiangsu University, Zhenjiang 212013, China.; Department of Chemistry, Faculty of Science, Menoufia University, Shebin El-Kom 32512, Egypt., Pare PW; Department of Chemistry & Biochemistry, Texas Tech University, Lubbock, TX 79409, USA., Hegazy MF; National Research Centre, Chemistry of Medicinal Plants Department, 33 El-Bohouth St., Dokki, Giza 12622, Egypt.; Department of Pharmaceutical Biology, Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg University, Staudinger Weg 5, 55128 Mainz, Germany. |
| Abstrakt: |
Centaurothamnus maximus (family Asteraceae), is a leafy shrub indigenous to the southwestern Arabian Peninsula. With a paucity of phytochemical data on this species, we set out to chemically characterize the plant. From the aerial parts, two newly identified guaianolides were isolated: 3β-hydroxy-4α(acetoxy)-4β(hydroxymethyl)-8α-(4-hydroxy methacrylate)-1α H ,5α H , 6α H -gual-10(14),11(13)-dien-6,12-olide ( 1 ) and 15-descarboxy picrolide A ( 2 ). Seven previously reported compounds were also isolated: 3β, 4α, 8α-trihydroxy-4-(hydroxymethyl)-lα H , 5α H , 6β H , 7α H -guai-10(14),11(13)-dien-6,12-olide ( 3 ), chlorohyssopifolin B ( 4 ), cynaropikrin ( 5 ), hydroxyjanerin ( 6 ), chlorojanerin ( 7 ), isorhamnetin ( 8 ), and quercetagetin-3,6-dimethyl ether-4'- O -β-d-pyranoglucoside ( 9 ). Chemical structures were elucidated using spectroscopic techniques, including High Resolution Fast Atom Bombardment Mass Spectrometry (HR-FAB-MS), 1D NMR; 1 H, 13 C NMR, Distortionless Enhancement by Polarization Transfer (DEPT), and 2D NMR ( 1 H- 1 H COSY, HMQC, HMBC) analyses. In addition, a biosynthetic pathway for compounds 1 - 9 is proposed. The chemotaxonomic significance of the reported sesquiterpenoids and flavonoids considering reports from other Centaurea species is examined. |
