Bonaspectins and neobonaspectins, first sesquilignans and sesquineolignans from a convolvulaceous species.

Four new tetrahydrofuran-type sesquilignans, named bonaspectin A, bonaspectin B, bonaspectin C 4''-beta-glucoside and bonaspectin D 4''-beta-glucoside, as well as two new 8.O.4'-type sesquineolignans, named neobonaspectin A and B, were isolated from the aerial vegetative parts of Bonamia spectabilis (Convolvulaceae), together with the known compound rel-(7S,8S,7'R,8'R)-3,3',4,4',5,5'-hexamethoxy-7.O.7',8.8'-lignan. Their structures were established on the basis of spectral data.

An expeditious procedure for the isolation of ingenol from the seeds of euphorbia lathyris

A short and practical process for the isolation of ingenol (1a) from an agricultural commodity (the seeds of Euphorbia lathyris) is described. Macrocyclic diterpene esters are obtained as byproducts, and the esterification pattern of the Euphorbia factors L2 (3), L3 (4a), and L8 (4b) was established by 2D NMR measurements. Full spectroscopic data for these compounds are reported.

Isoterracinolides A and B, novel bishomoditerpene lactones from euphorbia terracina

An extract of Euphorbia terracina L. has yielded six acylated polyhydroxy terpenoid lactones (1-6), which all display the C22 17-ethyljatrophane carbon framework. Four of these (1-4) are delta lactones belonging to the previously described terracinolide type, and two of them (2, 3) are new. Two further new compounds have been named isoterracinolides A (5) and B (6) and exhibit an eight-membered lactone ring. Another isolated new compound is the jolkinolide-type, ent-abietane gamma lactone (7).

Furohyperforin, a prenylated phloroglucinol from st. John's wort (Hypericumperforatum)

Furohyperforin, an oxygenated analogue of the prenylated phloroglucinol hyperforin, was isolated from the aerial parts of Hypericum perforatum. Its structure was elucidated as 2 on the basis of extensive NMR investigations.

Diterpenoids from euphorbia pithyusa subsp. cupanii

The aerial parts of Euphorbia pithyusa subsp. cupanii collected in Sardinia afforded eleven novel diterpenoids belonging to the lathyrane (1a), premyrsinane (4a-g), and tigliane (5a-c) types. Compounds 4a-g and 5a are esters of two new parent alcohols, named premyrsinol and 4,12,20-trideoxyphorbol, respectively. Structures were elucidated by spectroscopic and chemical methods. Puzzling differences between the NMR data of lathyrol (1c) and its esters were rationalized in terms of flipping of the exomethylene around the mean plane of the macrocycle.

Triterpenoid p-aminobenzoates from the seeds of zucchini.

An investigation of the triterpenoid fraction of zucchini seeds afforded two novel multiflorane p-aminobenzoates, identified as 7-epi zucchini factor A and debenzoyl zucchini factor B. Multiflorane p-aminobenzoates could not be detected in zucchini sprouts, which contained bryonolic acid as the only multiflorane constituent. No compound of this type could be obtained from adult plant parts (roots, stems, leaves).

Polycyclic diterpenoids from Euphorbia characias.

In addition to widespread flavonoids, a collection of Euphorbia characias from Sardinia afforded 13 oxygenated diterpenoids of the atisane, abietane, pimarane, and kaurane type. Four of these compounds (1, 3a, 7a,b) are new. The accumulation of substantial amounts of biologically active diterpenoids of limited availability, like ent-atisanes endowed with anti-HIV activity and ent-abietanolides active on the central nervous system, makes E. characias an interesting source of lead compounds for biomedical research.

[Diterpenes and other components of Croton hirtus (Euphorbiaceae)]. / Diterpenos y otros constituyentes de Croton hirtus (Euphorbiaceae).

The roots of Croton hirtus (Euphorbiaceae) collected in Paraiso, Cartago (Costa Rica) afforded, in addition to the few known metabolites, 20 new compounds: the bis-nor dolabradane 1, the dolabradanes 2 and 3, the kauranes 4-7, the cyclopropakauranes 8 and 9, the hirtusanes 10-15, the germacradiene esters 16-18 and the C-25 compound 21, presumably formed by a Diels-Alder reaction between compound 18 and a monoterpene. All structures were elucidated using high field 1D and 2D NMR techniques. MS fragmentation patterns are here reported. The absolute configurations of 4 and 9 were elucidated by using circular dichroism. The separation was performed with modern chromatographic technics.

Diterpenes and other constituents from Croton draco (Euphorbiaceae).

Croton draco (Euphorbiaceae) from Guadalupe, San José, Costa Rica was collected in July 1992 and phytochemically studied (leaves, seeds, wood, bark, sap and flowers separately). Commonly known compounds such as 1-hydroxyjunenol, p-hydroxybenzaldehyde, p-methoxybenzoic acid, 3,4,5-trimethoxycinnamyl alcohol, the coumarin scopoletin, the nor-terpenoids 9-dehydrovomifoliol and 2,3-dihydrovomifoliol were obtained. Taspine, two aporphinic alkaloids, the diterpenes 9(11)-dehydrokaurenic acid, hardwikiic acid, the corresponding new 12-oxo derivative as well as five clerodanes and a phorbol ester were also isolated. Three clerodanes were not previously described and their NMR spectroscopical data and MS fragmentation patterns are reported.

Sesquiterpenlactone aus berkheya-arten.

The aerial parts of BERKHEYA CARLINOPSIS ssp. MAGALISMONTANA afforded two new guaianolides closely related to subluteolide, while B. PAUCIFLORA gave desacetyl laurenobiolide and a costic acid derivative. The structures were elucidated by spectroscopic methods.

Structures of the two saponins isolated from commercially available root extract of Primula sp.

The two main saponins of commercially available extract of Primula sp. were isolated by HPLC. Their structures were elucidated by spectroscopic methods as already known primulasaponin (1) and the new 3-O-¿[alpha-rhamnopyranosyl-(1-->2)-beta- galactopyranosyl-(1-->3)-[beta-xylopyranosyl-(1-->4)-beta-glucopyranosyl - (1-->2)]-beta-glucuronopyranosyl]¿-protoprimulagenin A (2).

[Further Compounds from Centaurea stoebe.]. / Weitere Inhaltsstoffe aus Centaurea stoebe.

From CENTAUREA STOEBE the following compounds have been isolated: cnicin, salonitenolide, salonitenolid-8- O-(4'-acetoxy-5'-hydroxyangelate), stoebenolide, 3-hydroxy-2-methylbutyrolactone, and 3-(3, 4-dihydroxy-5-methoxyphenyl)-prop-1-yl 3-hydroxy-11-methyloctadecanoate.

New Pseudoguaianolides from Ambrosia maritima.

The investigation of the aerial parts of two collections of AMBROSIA MARITIMA afforded in addition to known pseudoguaianolides nine new ones including two nor-sesquiterpene lactones and two dimeric lactones. The structures were elucidated by highfield (1)H-NMR spectroscopy.

Further Sesquiterpene Lactones from Eupatorium altissimum.

A reinvestigation of the aerial parts of EUPATORIUM ALTISSIMUM afforded, in addition to several, previously isolated sesquiterpene lactones, five new ones. The structures of these were elucidated by highfield (1)H-NMR spectroscopy.

Germacra-1,10Z,4E-dien-12,8alpha-olides from Mikania micrantha.

The aerial parts of MIKANIA MICRANTHA from a collection in Paraguay gave, in addition to mikanolide, deoxymikanolide, and miscandenin, five new germacranolides all derived from 14,15-dihydroxygermacra-1(10) E,4 Z-dien-12,8alpha-olide.

Constituents of Evolvolus arbuscula ssp. canus.

From the aerial parts of EVOLVOLUS ARBUSCULA ssp. CANUS (Convolvulaceae) the nor-sesquiterpenoids, 15-norpanasinsan-5beta-ol-8-one, 15-nor-panasinsan-5,8-dione, and caryophyllenoxide, have been isolated together with some aliphatic compounds and sterols.

New melampolides from Acanthospermum australe.

In addition to known compounds nine new melampolides have been isolated from the aerial parts of ACANTHOSPERMUM AUSTRALE. The structures were established by spectroscopic means and by comparing the spectral data with those of related compounds.

Weitere Phloroglucin- und alpha-Pyron-Derivate aus Helichrysum-Arten.

The investigation of three South African HELICHRYSUM species afforded a tremetone derivative, where the acetyl group is methylated, four phloroglucin derivatives, two of them being chromones, four alpha-pyrone derivatives and a dihydro chalcone also derived from phloroglucine. The structures were elucidated by sepectroscopic methods.

Nor-ent-labdan Derivate aus Austroeupatorium inulaefolium.

From the aerial parts of AUSTROEUPATORIUM INULAEFOLIUM three nor-ent-labdane derivatives were isolated, their structures and stereochemistry could be determined by high field NMR spectroscopy.

Aromatic Constituents from Vladimiria souliei.

The polar parts of the title plant gave several lignans including six new ones named vladinol A-F. The structures were elucidated by high field (1)H-NMR spectroscopy and a few chemical reactions. The stereochemistry was determined by the observed NOE's and by comparison of the (1)H-NMR data with those of related lignans.