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Showing papers by "Tom J. Mabry published in 1990"


Journal ArticleDOI
TL;DR: In addition to the known phenylpropanoid myristicin, the petrol extract of the roots of Ferulago antiochia yielded six new germacrane esters and a new alloaromadendrane ester as mentioned in this paper.

29 citations



Journal ArticleDOI
TL;DR: The aerial parts of the Texas bitterweed Hymenoxys odorata yielded five guaianolide, four pseudoguaianolides, five modified pseudoguanolides and one aliphatic lactone, which were previously unreported.

24 citations


Journal ArticleDOI
TL;DR: From the above ground parts of Hymenoxys turneri, three unusual 2,3-dihydroflavonol 3-acetates, two other 2, 3-Dihydronols, two flavones and three sesquiterpene lactones were obtained by spectroscopy as mentioned in this paper.

17 citations


Journal ArticleDOI
TL;DR: In this article, the structures of the compounds were elucidated by NMR and mass spectroscopy, and five inositol derivatives and two pseudoguaianolides were found.

16 citations


Journal ArticleDOI
TL;DR: The dichloromethane extract of the leaves and flowers of Hymenoxys biennis afforded an adduct of the modified pseudoguaianolide hymenoxon and a guaianolides as well as three guaIANolide glucosides, seven sesquiterpene lactone aglycones, two inositol derivatives and an aliphatic lactone.

14 citations


Journal ArticleDOI
TL;DR: The dichloromethane extract of Hymenoxys lemmonii afforded 13 sesquiterpene lactones, including four known and two new aglycones and two known and five new glycosides.

13 citations


Journal ArticleDOI
TL;DR: In this article, only apigenin-based C-glycosylflavones that are methylated either at the 7-and 4-position, only the 7 position, or not methylated at all were found.

11 citations


Journal ArticleDOI
TL;DR: In this paper, six guaianolides, seven pseudoguaianolide and an aliphatic lactone were isolated from Hymenoxys scaposa var. villosa.

10 citations


Journal ArticleDOI
TL;DR: The first report of 6-methoxy-kaempferol 7,4′-dimethyl ether 3-sulphate was made by as discussed by the authors, and the known compounds: 6-methyl ether and quercetagetin 6,7, 4′-trimethyl ether (3-SULPHATE) were reported from Brickellia longifolia.

5 citations


Journal ArticleDOI
TL;DR: The conformation of the progesterone side chain is similar to the conformation observed in other 17 alpha-ester pregnanes: C16-C17-C20-O20 torsion angle -27.4(3) degrees.
Abstract: C24H30O4, Mr = 382.5, orthorhombic, P212121, a = 13.091 (2), b = 19.711 (1), c = 8.242 (1) A, V = 2126.7 (5) A3, Z = 4, Dx = 1.195 Mg m-3, lamba (Cu K alpha) = 1.54184 A, mu(Cu K alpha) = 0.56 mm-1, F(000) = 824, T = 295 K. Final R = 0.045 for 2446 unique reflections. The planar A ring is bent relative to the rest of the steroid skeleton. The B ring has a typical chair conformation and the C and D rings assume 13 beta,14 alpha-half-chair and 13 beta-envelope conformations, respectively. The conformation of the progesterone side chain is similar to the conformation observed in other 17 alpha-ester pregnanes: C16-C17-C20-O20 torsion angle -27.4(3) degrees.

Journal ArticleDOI
TL;DR: In this article, a 3,2'-dioxygenated flavonoids with planarity reduction and reduced conjugation of the B-ring chromophore with the A-ring was studied.
Abstract: C20H20O10, Mr = 420.37, triclinic, P1, a = 8.771 (3), b = 13.508 (3), c = 15.970 (4) A, alpha = 86.04 (2), beta = 81.77 (2), gamma = 84.17 (2) degrees, V = 1860.0 (8) A3, Z = 4 (two molecules per asymmetric unit), Dm (by flotation in ZnCl2/H2O solution at 298 K) = 1.491, Dx = 1.503 g cm-3, Mo K alpha radiation, lambda = 0.71069 A, mu = 1.14 cm-1, F(000) = 880, T = 163 K. Full-matrix least-squares refinement converged to R = 0.039 and wR = 0.037 using 5198 reflections with I greater than 3 sigma (I). The two molecules in the asymmetric unit differ in the torsion angles involving the methoxy groups and in the dihedral angle between the planes of rings B and C, 33.31 (7) and 40.83 (7) degrees in molecules (I) and (II), respectively. This compound belongs to a class of 3,2'-dioxygenated flavonoids whose ultraviolet (UV), mass spectroscopic (MS) and chromatographic properties indicate that in solution these compounds have reduced planarity (and thus reduced conjugation) of the B-ring chromophore with the A, C-ring chromophore.

Journal ArticleDOI
TL;DR: The planar A ring has a typical chair conformation and the C and D rings assume 13 beta, 14 alpha-half-chair and 13 beta-envelope conformations, respectively.
Abstract: C24H30O4, Mr = 382.5, orthorhombic, P212121, a = 13.091 (2), b = 19.711 (1), c = 8.242 (1) A, V = 2126.7 (5) A3, Z = 4, Dx = 1.195 Mg m-3, lamba (Cu K alpha) = 1.54184 A, mu(Cu K alpha) = 0.56 mm-1, F(000) = 824, T = 295 K. Final R = 0.045 for 2446 unique reflections. The planar A ring is bent relative to the rest of the steroid skeleton. The B ring has a typical chair conformation and the C and D rings assume 13 beta,14 alpha-half-chair and 13 beta-envelope conformations, respectively. The conformation of the progesterone side chain is similar to the conformation observed in other 17 alpha-ester pregnanes: C16-C17-C20-O20 torsion angle -27.4(3) degrees.