Kolavane and kaurane diterpenes from the stem bark of Xylopia aethiopica

The stem bark of Xylopia aethiopica has yielded four diterpenes, two of them novel. Three of the diterpenes were identified as (?)-kaur-16-en-19-oic acid and its 7-oxo and 7β-hydroxy derivatives. The fourth was the novel kolavane derivative 2-oxo-kolav-3,13-dien-15-oic acid, a type of compound not previously recorded in the Annonaceae.     

Sesquiterpene lactones and diterpenoids from Helianthus argophyllus

Three germacranolide sesquitepene lactones (argophyllin-A and -B and eupatolide), three diterpenoids (ciliaric acid, (?)-16-α-hydroxy-kaur-11-en-19-oic acid and (?)-16-α-hydroxykaurane) and one flavonoid (nevadensin) were isolated and characterized from a chloroform extract of Helianthus argophyllus. Argophyllin-A and -B are both described here for the first time. Their structures were deduced by ¹H NMR and ¹³C NMR. Argophyllin-A and -B were found to show anti-auxin effects while eupatolide exhibited weak insecticidal activity.     

Kaurane and kaurene diterpenes from the stem bark of Xylopia acutiflora

Four diterpenes were isolated from the stem bark of Xylopia acutiflora and characterized as (?)-kauran-16α-ol, 7,8-acetoxy-(?)-kaur-16-en-19-oic acid, 15-oxo-(?)-kaur-16-en-19-oic acid, and 16α- hydroxy-(?)-kauran-19-oic acid.     

Ent-kauranes and trachylobanes from Helianthus radula

The aerial parts of Helianthus radula afforded a variety of known ent-kauranoic acids as well as two new substances, 11-oxotrachyloban-19-oic a     

Triterpenoids from Hyptis suaveolens roots

A new natural triterpenoid, 3β-hydroxylup-12-en-28-oic acid, has been isolated from the roots of Hyptis suaveolens in addition to α- and β-amyrin.     

Essential oil and terpenoids of Mikania micrantha

Twenty-seven mainly terpenoid constituents were identified in the essential oil of Mikania micrantha whole plant. Higher terpenoids present in the same plant included two kaurene derivatives and taraxasterol.     

Diterpenoids from Viguiera insignis

The isolation of several known diterpenoids and one new diterpene diol from aerial parts of Viguiera insignis is reported.     

Terpenoids of Canarium zeylanicum

The following terpenoids were identified in the oleoresin, bark and timber of Canarium zeylanicum: 3β-hydroxyurs-12-en-11-one, 3β-hydroxyolean-12-en-11-one, olean-12-en-3,11-dione, urs-12-en-3,11-dione, α- and β-amyrin, α- and β-amyrenone, taraxerol, sitosterol, canaric acid, elemene, elemol, α-pinene, α- and β-phellandrene, limonene, terpineol and carvone.     

13C NMR spectral analysis of eperuane diterpenes

The ¹³C NMR spectra of some eperuane diterpenes have been recorded and the signals assigned. The substituent shielding effects in these compounds, in comparison with those observed in other series of diterpenes, are also presented.     

Terpenoids from the seed of platycladus orientalis

Four labdane-type diterpenoids have been isolated from the seed of Platycladus orientalis. Their structures have been elucidated by spectroscopic and chemical methods.     

Two triterpenoid carboxylic acids from Acanthopanax trifoliatus

Two new triterpenoid carboxylic acids have been isolated from leaves of Acanthopanax trifoliatus and their structures elucidated as 3α, 11α-dihydroxylup-20(29)-en-28-oic acid and 30α, 11α,23-trihydroxylup-20(29)-en-28-oic acid by physical data and chemical transformations.     

8β-hydroxypimar-15-en-19-oic acid from Taxodium mucronatum

A new diterpenoid has been isolated from the leaves and fruits of Taxodium mucronatum. Its structure, 8β-hydroxypimar-15-en- 19-oic acid, was established by chemical and spectroscopic means.     

3α-Hydroxy-multiflora-7,9(11)-dien-29α-oic acid,a new triterpene from Bryonia dioica

The structure of a new triterpene acid from the roots of Bryonia dioica is shown on the basis of chemical and spectroscopic evidence to be 3α-hydroxy-multiflora-7,9(11)-dien-29α-oic acid. This is the first report of a naturally occurring Δ^7,9(11) -multiflorene compound.     

Sapogenins from Guaiacum officinale

Acid hydrolysis of the saponins from the stem bark of Guaiacum officinale yielded the new sapogenin 3β,20η-dihydroxy-30-norolean-12-en-28-oic acid and the artifacts 3β-hydroxy-30-norolean-12,19-dien-28-oic acid and its methyl ester. Larreagenin, sitosterol and oleanolic acid were also isolated.     

A kolavane derivative from Liatris scariosa

A new kolavane derivative, 18-acetoxy-kolav-3-en-15-oic acid, has been isolated from Liatris scariosa.     

Two 24-nor-triterpenoid carboxylic acids from acanthopanax trifoliatus

From Acanthopanax trifoliatus the new nor-triterpenes 24-nor-3α, 11α-dihydroxy-lup-20(29)-en-28-oic acid and 24-nor-11α-hydroxy-3-oxo-lup-20(29)-en-28-oic acid were isolated. Their structures were determined on the basis of spectroscopic data, X-ray analysis and chemical transformations.