Anthraquinones in Ventilago species

Eleven anthraquinones have been isolated from the root bark of Ventilago calyculata of which xanthorin-5-methyl ether and 2-hydroxyislandicin are n     

Three further naphthoquinones produced by Fusarium solani

Three naphthoquinone pigments are described which were produced by Fusarium solani. They are 2,3-dihydro-5,8-dihydroxy-6-methoxy-2-hydroxymethyl-3-(2-hydroxypropyl)-1,4-naphthalenedione, 2,3-dihydro-5-hydroxy-4-hydroxymethyl-8-methoxy-naphtho[1,2-b]furan-6,9-dione and 5,8-dihydroxy-2-methoxy-6-hydroxymethyl-7-(2-hydroxypropyl)-1,4-naphthalenedione. One of these pigments was shown to be the precursor of the other two.     

Naphthoquinones and triterpenes from african Diospyros species

Investigation of the bark and/or wood of seventeen African species of Diospyros has revealed the presence of a number of triterpenes and naphthoquinones. The triterpenes lupeol, betulin and betulinic acid were detected in all samples but three other triterpenes were each found in only one species; betulinaldehyde in D. canaliculata, cerin in D. iturensis, and glutinol in D. zenkeri. Naphthoquinones were detected in fourteen of the seventeen species and the common dimeric compounds diospyrin, isodiospyrin and diosindigo-A were isolated. D. canaliculata differed from all other species in producing derivatives of plumbagin including its reduced form, isoshinanolone (1R,2R) and a novel stereoisomer which was given the trivial name epiisoshinanolone (1S,2R).     

Benzisochromanquinones in ventilago species

From the acetone extract of the root bark of Ventilago maderaspatana eight new benzisochromanquinones; ventiloquinones A, B, C, D, E, F, G and H, have been isolated. Ventiloquinones I, J and K are three more new benzisochromanquinones isolated from the root bark of V. calyculata. The majority are 3,4,5,10-tetrahydro-cis-1,3-dimethyl-1H-naphtho[2,3-c]pyran-5,10-quinones related to eleutherin, but F, H, I, J and K are 6,9-quinones related to ventilagone.     

Naphthoquinones and triterpenes from some asian Diospyros species

Investigation of the stem bark, wood and/or fruit of nine Asian Diospyros spp. (Ebenaceae) has revealed a range of triterpenes and naphthoquinones     

Pseudoguaianolides and other sesquiterpene lactones from Gaillardia species

The aerial parts of two Gaillardia species afforded in addition to known sesquiterpene lactones 23 new pseudoguaianolides, two dugaldiolide derivatives and two seco-neopulchellin derivatives. The structures were elucidated by spectroscopic methods. Biogenetic relationships are discussed briefly.     

Eremophilane derivatives and other constituents from Senecio species

The investigation and reinvestigation respectively of 23 Senecio species afforded 11 further cacalol derivatives, a furoeremophilone, 17 eremophilanes, 4 bisabolene derivatives, a shikimic acid derivative, a bis-prenylated p-hydroxybenzaldehyde, menth-2-en- 1,7-diol and a cumol derivative. The configuration of some eremophilanes have been revised. Structures were elucidated by spectroscopic methods. The results are summarized in a table. The chemotaxonomic aspects agree with those of previous investigations.     

Naphthoquinone-lactones and extended quinones from Ventilago calyculata

New quinones have been isolated from the root bark of Ventilago calyculata. Ventilatones A and B are benzisochromanquinones, related to the ventiloquinones, which have an additional fused lactone ring while ventileins A and B are benzisochroman dimers having a dihydroxy-peri-xanthenoxanthenequinone chromophore.     

Diterpenoid furans from Pterodon species

Investigation of diterpenoids in four species of Pterodon show varying oxidation patterns on the vinhaticane or vouacapane skeletons.     

Seven sesquiterpene lactones from Ferreyanthus species

The investigation of two Ferreyanthus species afforded seven germacranolides which have not been isolated previously. Two derivatives of linalol were also present. The structures were elucidated by spectroscopic methods. Chemotaxonomic relationships are briefly discussed.     

Naphthoquinones produced by Fusarium oxysporum isolated from citrus

Six naphthoquinone pigments are described which were produced by Fusarium oxysporum isolates obtained from roots of diseased citrus trees. These were 8-O-methylbostrycoidin, 9-O-methylfusarubin, 9-O-methylanhydro-fusarubin, 5-O-methyljavanicin, 5-O-methylsolaniol and 1,4-naphthalenedione-3,8-dihydroxy-5,7-dimethoxy-2-(2-oxopropyl). These naphthoquinones had not been previously identified from F. oxysporum isolates.     

A new peptide alkaloid from Discaria crenata

The structure of a new peptide alkaloid, crenatine A isolated from Discaria crenata, has been elucidated.     

New peptide alkaloids from Hovenia dulcis and H. tomentella

From the root bark of Hovenia dulcis Thunb. and H. tommentella (Makino) Nakai (Rhamnaceae), three peptide alkaloids, frangulanine, hovenins-A and -B have been isolated. Hovenin-A has been shown to be des-N-methylfrangulanine (II).     

Bisabolene derivatives and acetylenic compounds from peruvian Coreopsis species

The investigation of three Peruvian Coreopsis species afforded, in addition to compounds isolated previously from this genus, two new tetraynenes and five sesquiterpenes all related to perezone, including a tricyclic ketone with a cedrane skeleton closely related to pipitzol. The structure were elucidated by spectroscopic methods.     

Faralatroside and faratroside,two flavonol triglycosides from Colubrina faralaotra

Two new flavonol triosides have been isolated from the leaves of Colubrina faralaotra (Rhamnaceae) and their structures elucidated as kaempferol-3-O-[β-d-glucopyranosyl-(1 → 3)-4″′-O-acetyl-α-l-rhamnopyranosyl-(1 → 6)-β-d-galactopyranoside] and the corresponding quercetin analogue mainly by ¹H and ¹³C NMR spectroscopy (including T₁, measurements).     

Coumarins from Pterocaulon balansae and P. lanatum

Analysis of the petrol-diethyl ether extracts of Pterocaulon balansae and P. lanatum aerial parts afforded, besides puberulin, scopoletin-[2′     

Rhamnazin- und rhamnetin-3-O-trioside aus Rhamnus petiolaris

From the fruits of Rhamnus petiolaris two new flavonol-3-O-triosides were isolated and identified as rhamnazin-3-O-[α-l-rhamnopyranosyl (1 → 4)-α-l-rhamnopyranosyl (1 → 6)]-β-d-galactopyranoside and rhamnetin-3-O-α-l-rhamnopyranosyl (1 → 2)-α-l-rhamnopyranosyl (1 → 6)]-β-d-galactopyranoside, respectively.     

C-galactosylflavones from Polygonatum multiflorum

8-C-Galactosylapigenin and 6-C-galactosyl-8-C-arabinosylapigenin were isolated from the leaves of Polygonatum multiflorum (L.) All. Structural assignments for the latter compound were made on the basis of mass, CD and ¹³C-NMR spectra.     

The structure of jujubosides A and B,the saponins isolated from the seeds of Zizyphus jujuba

Stepwise chemical and enzymatic hydrolyses of jujubosides A and B, the saponins of the seeds of Zizyphus jujuba, afforded prosapogenins I, II and III. The sequence and configuration of the sugar linkages in the saponins and the pro-sapogenins were determined from the PMR data and the application of Klyne's rule of molecular rotations and structures were assigned to jujubosides A and B.