In addition to some known chalcones and ecdysteroids three new chalcones have been isolated from aerial parts of Vitex leptobotrys, the structures of which have been identified as 2′,4′-dihydroxy-4,6′-dimethoxychalcone, 4′-hydroxy-4,2′,6′-trimethoxychalcone and 4,2′,4′,β-tetrahydroxy-6′-methoxy-α,β-dihydrochalcone, respectively.

A new triterpene, 3α,20-dihydroxy-3β,25-epoxylupane, was isolated and structurally elucidated from flowers of the sumach tree Rhus typhina (Anacardiaceae).

Racemization and stability of the betacyanins, betanin (betanidin 5-O-glucoside) and amaranthin(betanidin 5-O-glucuronosylglucoside), under acidic conditions were compared with those of the corresponding feruloyl derivatives, lampranthin II and celosianin II. Both acylbetacyanins showed a reduced racemizationvelocity and celosianin II in addition an enhanced stability, possibly caused by intramolecular associationbetween the betanidin and the feruloyl moieties.

Formation of betanidin, the aglycone of the red–violet betacyanins, has been demonstrated by a two-step model assay system. In the first step, dihydroxyphenylalanine (Dopa) was incubated with a Dopa dioxygenase preparation from Amanita muscaria, resulting in the formation of 4,5-seco-Dopa that spontaneously recyclized to betalamic acid. In the second step, a tyrosinase preparation from Portulaca grandiflora was added to the Dopa dioxygenase assay, resulting in Dopa oxidation followed by a spontaneous formation of cyclo-Dopa that, in turn, reacted spontaneously with betalamic acid to form betanidin. Thus, two enzymatic reactions, Dopa extradiol ring cleavage by the fungal enzyme and Dopa oxidation by the plant enzyme, initiate three spontaneous steps: the formation of cyclo-Dopa and betalamic acid and finally the condensation of these compounds to betanidin.

Two new peptide alkaloids, scutianines-K and -L were isolated from Scutia buxifolia, a plant growing in Brazil, Argentina and Uruguay. Their structures have been determined on the basis of spectroscopic studies. The stereochemistry of the N,N-dimethyl amino acid side-chain and the ring amino acid residues in both alkaloids have been assigned by gas chromatography employing modified cyclodextrins as chiral stationary phases.

A new jasmonate, N-[(—)-jasmonoyl]-tyramine, was identified from petunia pollen in which (—)-jasmonic acid was detected and quantified.

In addition to (-)-mehranine, hecubine, ibogaine, ibogaline, 19R-epi voacristine, 20-hydroxyconopharyngine and pedunculine the novel indole alkaloids 3-oxomehranine and 14α,15β-dihydroxy-N-methylaspidospermine have been isolated from the leaves and stems of Tabernaemontana bovina. The structure of 3-oxomehranine has been assigned by NMR investigations, the structure of 14α,15β-dihydroxy-N-methylaspidospermine by X-ray analysis and their absolute configurations by circular dichroism.

Exogenously applied 3-dehydro-24-epi-teasterone is transformed by cell suspension cultures of Lycopersicon esculentum to give the metabolites 24-epi-teasterone and 24-epi-typhasterol in about equal but low quantities. The major portion of 24-epi-teasterone was found as carbohydrate conjugates while 24-epi-typhasterol occurred in free form, indicating significant influence of glycosidation on the equilibrium between both compounds. The importance of these conjugation processes for the regulation of the brassinosteroid biosynthesis is discussed.In tomato cell cultures, 3-dehydro-24-epi-teasterone is transformed both to 24-epi-teasterone and 24-epi-typhasterol. The ratio between both epimers is regulated by glycosidation in 3β-position

In addition to some known chalcones and ecdysteroids three new chalcones have been isolated from aerial parts of Vitex leptobotrys, the structures of which have been identified as 2′,4′-dihydroxy-4,6′-dimethoxychalcone, 4′-hydroxy-4,2′,6′-trimethoxychalcone and 4,2′,4′,β-tetrahydroxy-6′-methoxy-α,β-dihydrochalcone, respectively.

A new triterpene, 3α,20-dihydroxy-3β,25-epoxylupane, was isolated and structurally elucidated from flowers of the sumach tree Rhus typhina (Anacardiaceae).