Search results for "Terpene"
showing 10 items of 816 documents
Biologically and Pharmacologically Active Saponins from Plants: Recent Advances
2000
Saponins as triterpene or steroid glycosides were well known in ancient times for their detergent, haemolytic and fish toxic activities, properties which are correlated with the amphiphilic character of the molecules and their ability to complex cholesterol.
Neo-clerodane diterpenoids from Teucrium kotschyanum
1989
Abstract From the aerial parts of Teucrium kotschyanum three new neo-clerodane diterpenoids have been isolated. Their structures, (12R)-15,16-epoxy-19-nor-10α-neo-cleroda-4,13(16),14-triene-18,6β; 20,12-diolide (12-epiteucvidin), (12R)-15,16-epoxy-19-nor-neo-cleroda-4,13(16),14-triene-18,6β; 20,12-diolide (12-epiteufiin) and (12S,18R)-15,16-epoxy-6β-hydroxy-neo-cleroda-13(16),14-dien-20,12-olide-l8,19-hemiacetal (teukotschyn), have been established by chemical and spectroscopic means. In addition, ursolic acid, the flavones cirsimaritin and cirsiliol, and six previously known neo-clerodane diterpenoids (teucvidin, teuflin, teuscorodin, teucrin H2, teuscorodonin and montanin D) were also fou…
Synthetic studies toward natural furanosesquiterpenoids from santonin. Synthesis of (+)-1,2-dihydrotubipofuran
1994
Abstract Santonin (1) was converted into (+)-1,2-dihydrotubipofuran (13) via a synthetic pathway involving a very easy preparation of 7,11-ene-8,12-olide and 8,12-furan moieties and A-ring elaboration on the eudesmane framework.
Bonandiol: A new, irregular, monocyclic diterpene from (L.) Halacsy (umbelliferae)
1984
A new, irregular, monocyclic diterpene, bonandiol (1), has been isolated from Bonannia graeca. The structure of bonandiol has been deduced from spectral data and chemical evidence.
Sesquiterpene lactones, flavonoids and coumarins from Centaurea collina
1989
Abstract The isolation and characterization of two coumarins, five flavonoids and four sesquiterpene lactones from the aerial parts of Centaurea collina are reported. The 13 C NMR data are included.
A minor diterpene from Amaracus akhdarensis
1985
Abstract A new isopimarane diterpenoid, isoakhdartriol, was isolated in very small amount from the aerial part of Amaracus akhdarensis. Its structure, isopimar-15-en-3β,8β,19-triol, was established by spectroscopic means.
Jatrophane and tigliane diterpenes from the latex of Euphorbia obtusifolia
1999
The latex of Euphorbia obtusifolia var. obtusifolia yielded twelve new diterpene polyesters. Seven of them displayed the jatrophane framework and five were 4-deoxyphorbol esters. A further isolated tigliane diterpene, a derivative of 4-epi-4-deoxyphorbol, was most likely an artifact of the isolation procedure. All structures were established with the aid of spectroscopic methods.
13C nuclear magnetic resonance spectra of several podocarpane and cassane diterpenoids
1990
The 13C NMR spectra of several diterpenic derivatives having the podocarpane and cassane skeleton were recorded and interpreted. The most significant effects due to substituent orientation, B/C ring junction stereochemistry and conformational changes are briefly discussed.
New Sesquiterpene Lactones and Other Constituents fromCentaurea paui
1997
Aerial parts of Centaurea paui afforded, in addition to several known sesquiterpene lactones, the two new elemanolides 2–4, the new elemane derivative 5 as well as the five new heliangolides 14–18. Their structures were elucidated by spectroscopic methods, especially high-field NMR spectroscopy. The structure of the heliangolide 12 previously isolated from this plant, has been confirmed by X-ray diffraction.
A sesquiterpene ester from Lactuca serriola
1992
Abstract The aerial parts of Lactuca serriola yielded a new guaiane ester together with five known guaianolides.