9-Hydroxy-4,8-dimethyl-12-(pyrrolidin-1-ylmethyl)-3,14-dioxatricyclo[9.3.0.02,4]tetradec-7-en-13-one (original) (raw)
Related papers
Acta Crystallographica Section E Structure Reports Online, 2011
The title compound, C 20 H 31 NO 5 , was synthesized from 9hydroxyparthenolide (9-hydroxy-4,8-dimethyl-12-methylen-3,14-dioxa-tricyclo[9.3.0.0 2 , 4 ]tetradec-7-en-13-one), which was isolated from the chloroform extract of the aerial parts of Anvillea radiata. The molecule is built up from fused five-and ten-membered rings with the pipyridin-1-yl-methyl group as a substituent. The ten-membered ring adopts an approximate chair-chair conformation, while the six-and five-membered rings display chair and envelope conformations, respectively. The dihedral angle between the mean planes of the tenmembered ring and the lactone ring is 20.8 (3). An intramolecular O-HÁ Á ÁN hydrogen-bond occurs. The crystal structure is stabilized by weak intermolecular C-HÁ Á ÁO hydrogen bonds. References Bruker (2005). APEX2 and SAINT.
Bioactive Cembrane Diterpenoids of Anisomeles indica
Journal of Natural Products, 2008
Five new cembrane-type diterpenoids with a trans-fused R-methylene-γ-lactone (1-5), a new flavonoid glucoside (6), and 17 known compounds were isolated from a methanol extract of Anisomeles indica. The structures of 1-6 were elucidated by spectroscopic analysis, and the absolute configuration of compound 1 was determined using the modified Mosher's method. Compound 8 (4,5-epoxovatodiolide) exhibited cytotoxicity against a small panel of human cancer cell lines. Additionally, compounds 4 and 7 (ovatodiolide) exhibited selective antiplatelet aggregation activities toward collagen, while compounds 4, 5, and 8 showed inhibitory effects on antiplatelet aggregation induced by thrombin.
Guaianolide Sesquiterpene Lactones from Centaurothamnus maximus
Molecules, 2021
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)-1αH,5αH, 6αH-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)-lαH, 5αH, 6βH, 7αH-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; 1H, 13C NMR, Distortionless Enhancement by Polarization Transfer (DEPT), and...
Absolute Configuration of a Diterpene Lactone fromParinari capensis
Helvetica Chimica Acta, 1997
' 3C-NMR: 87.2 ppm) indicated that 1 was a modified kaurenoid with the Me group at C(10) shifted to C(9) [4]. It was, therefore, identified as the 10-hydroxy-13-methoxy-9methyl-1 5-oxo-20-norkaur-16-en-18-0ic acid y-lactone. Further 2D-NMR experiments (COSY, HMBC and HMQC) allowed us the full assignment of the C-atoms (Table). Crystals obtained from hexane/AcOEt were subjected to X-ray analysis (Fig. I). The structure of 1 was thus confirmed and relative configurations at C(4), C(5), C(8), C(9), C(lO), and C(13) were determined.
Acta Crystallographica Section E Crystallographic Communications, 2015
The title compound, C19H29NO4S, was synthesised from 9α-hydroxyparthenolide (9α-hydroxy-4,8-dimethyl-12-methylene-3,14-dioxatricyclo[9.3.0.02,4]tetradec-7-en-13-one), which was isolated from the chloroform extract of the aerial parts of the plantAnvillea radiata. The molecule is built up from two fused five- and ten-membered rings, with an additional epoxy ring system and a thiomorpholine group as a substituent. The ten-membered ring adopts an approximate chair–chair conformation, while the thiomorpholine ring displays a chair conformation and the five-membered ring has an envelope conformation, with the C atom closest to the hydroxy group forming the flap. An intramolecular O—H...N hydrogen bond closes anS(8) ring. The crystal structure features weak C—H...O hydrogen-bonding interactions, which link the molecules into [010] chains.