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4-Hydroxyandrost-4-ene-3,17-dione is a second generation, irreversible aromatase inhibitor and commonly used as anti breast cancer medication for postmenopausal women. 4-Hydroxytestosterone is advertised as anabolic steroid and does not have any therapeutic indication. Both substances are prohibited in sports by the World Anti-Doping Agency, and, due to a considerable increase of structurally related steroids with anabolic effects offered via the internet, the metabolism of two representative candidates was investigated. Excretion studies were conducted with oral applications of 100mg of 4-hydroxyandrostenedione or 200mg of 4-hydroxytestosterone to healthy male volunteers. Urine samples were analyzed for metabolic products using conventional gas chromatography-mass spectrometry approaches, and the identification of urinary metabolites was based on reference substances, which were synthesized and structurally characterized by nuclear magnetic resonance spectroscopy and high resolution/high accuracy mass spectrometry. Identified phase-I as well as phase-II metabolites were identical for both substances. Regarding phase-I metabolism 4-hydroxyandrostenedione (1) and its reduction products 3beta-hydroxy-5alpha-androstane-4,17-dione (2) and 3alpha-hydroxy-5beta-androstane-4,17-dione (3) were detected. Further reductive conversion led to all possible isomers of 3xi,4xi-dihydroxy-5xi-androstan-17-one (4, 6-11) except 3alpha,4alpha-dihydroxy-5beta-androstan-17-one (5). Out of the 17beta-hydroxylated analogs 4-hydroxytestosterone (18), 3beta,17beta-dihydroxy-5alpha-androstan-4-one (19), 3alpha,17beta-dihydroxy-5beta-androstan-4-one (20), 5alpha-androstane-3beta,4beta,17beta-triol (21), 5alpha-androstane-3alpha,4beta,17beta-triol (26) and 5alpha-androstane-3alpha,4alpha,17beta-triol (28) were identified in the post administration urine specimens. Furthermore 4-hydroxyandrosta-4,6-diene-3,17-dione (29) and 4-hydroxyandrosta-1,4-diene-3,17-dione (30) were determined as oxidation products. Conjugation was diverse and included glucuronidation and sulfatation.

Three new iridals were isolated from rhizomes of Iris cristata. After spectral analysis their structures were respectively established as 22,23-epoxy-21-hydroxyiridal 5, 22,23-epoxyiridal 6 and 22,23-epoxy-10-deoxy-21-hydroxyiridal 7.

The metabolism of iridals, unusual triterpenoids found in sword lilies, was studied in a cell culture of Iris pseudacorus Linn. The cells contain mainly spiroiridals, esterified with capric acid, which are hydrolyzed by esterases upon cell disruption. In ether extracts of these cell homogenates 10-desoxyiridal, a hitherto unknown precursor of the iridals, was identified by comparison with a semisynthetic standard. The compound was isolated and its structure verified by spectroscopic means. Upon incubation of the cells with 3-amino-1,2,4-triazole, a bleaching agent, the amounts of iridal and 10-desoxyiridal in the cells increase, whereas the level of the conjugated iridotrienes is diminished. This proves that 10-desoxyiridal plays a central role in iridal biosynthesis and that the conjugated triene moiety of the iridotrienes is formed by the action of a desaturase on iridal.

Numerous 2-methoxy-6-n-alkyl-1,4-benzoquinones with interesting biological activities have been found as constituents of plants and plant seeds. The most prominent is primin, the n-pentyl derivative, which is stored in trichomes on leaves and stems of Primula obconica and is responsible for primrose dermatitis. The biosynthesis of primin was studied by feeding experiments with radioactively labelled precursors and unlabelled homologues.

Dehydration of slices of rhizomes led to an increase of iridal esters (IE) with a concomitant drop of free iridals (FI), as well as phospholipids (PL), in the drought-resistant species, Iris germanica . By contrast, in the wetland species, I. pseudacorus , lysis of IE is observed, while the PL content remains around the control level. The origin of fatty acids incorporated into IE and the possible role of iridals against stress injury within Iris species are discussed.

The metabolism of iridals, unusual triterpenoids found in sword lilies, was studied in a cell culture of Iris pallida . By incubation of the cells with radioactively labelled and unlabelled compounds the biogenetic pathway from iridal, the parent compound of the family, to the spiroiridals was shown to lead via 26-hydroxyiridal, which is dehydrogenated to form the corresponding 26-hydroxytriene. A dehydration of the 16- or 17-hydroxyiridals, respectively, was not observed. All triterpenoids are readily taken up by the cells from the medium and are esterified at C3, predominantly with medium-chain fatty acids.

Two novel nortriterpenoids and two, hitherto unknown, representatives of the rare malabaricane and polypodane type, respectively, were found in the neutral fraction of gum mastic, the resin ofPistacia lentiscus. In addition, several tri-, tetra- and pentacyclic triterpenes were identified. The significance of these results for the geometry of the epoxyqualene cyclase/substrate interaction inPistacia lentiscus is discussed.

A new iridal has been isolated from rhizomes of Iris germanica var. “Rococo”. On the basis of spectral data, its structure was established as 18,19-epoxy-10-deoxyiridal (5). This compound is the first epoxidized iridal discovered so far.

Roots of gramineous plants turn deep yellow upon colonization with arbuscular mycorrhizal fungi. At the same time methanolic extracts of maize roots show a polyene absorption with maxima at 375 and 395 nm that is not found in the extracts of controls. After esterification with diazomethane the compound responsible for this absorption was isolated by column chromatography and shown to be all- E -4,9-dimethyldodeca-2,4,6,8,10-pentaenedioic acid by NMR and mass spectrometry. The compound presumably is derived from oxidative degradation of a carotenoid.

(−)-trans-7(S)-Methoxytetradec-4-enoic acid and the related amides, malyngamides A, B and C, were found as constituents of shallow-water varieties of the marine blue-green alga Lyngbya majuscule.

The crystal structure of pukeleimide C, a novel pyrrolic compound from a shallow-water variety of the marine blue-green alga Lyngbya majuscula , is reported.

(+)-α(S)-Butyramido-γ-butyrolactone is a minor constituent of the toxic marine blue-green alga Lyngbya majuscula .