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Publikationen - Natur- und Wirkstoffchemie

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Publikation

Bringmann, G.; Schlauer, J.; Rischer, H.; Wohlfarth, M.; Mühlbacher, J.; Buske, A.; Porzel, A.; Schmidt, J.; Adam, G.; Revised Structure of Antidesmone, an Unusual Alkaloid from Tropical Antidesma Plants (Euphorbiaceae) Tetrahedron 56, 3691-3695, (2000) DOI: 10.1016/S0040-4020(00)00289-1

The structure of antidesmone, an alkaloid from Antidesma membranaceum Müll. Arg. and A. venosum E. Mey. (Euphorbiaceae), was revised to be (S)-4,8-dioxo-3-methoxy-2-methyl-5-n-octyl-1,4,5,6,7,8-hexahydroquinoline [(S)-2], not the isoquinoline derivative 1, as assumed previously. The revision was initiated by biosynthetic feeding experiments of one of our groups.
Publikation

Blitzke, T.; Masaoud, M.; Schmidt, J.; Constituents of Eulophia petersii Fitoterapia 71, 593-594, (2000) DOI: 10.1016/S0367-326X(00)00169-6

The isolation of five known phenanthrenes and a mixture phytosterols from roots of Eulophia petersii is reported.
Publikation

Blitzke, T.; Porzel, A.; Masaoud, M.; Schmidt, J.; A chlorinated amide and piperidine alkaloids from Aloe sabaea Phytochemistry 55, 979-982, (2000) DOI: 10.1016/S0031-9422(00)00269-7

Phytochemical investigations of Aloe sabaea afforded a new chlorinated amide, N-4′-chlorobutylbutyramide, and the toxic piperidine alkaloids coniine, γ-coniceine and the quarternary N,N-dimethylconiine. This is the first report of the occurrence of a chlorinated compound in the Aloeaceae family.
Publikation

Aulinger, K.; Arnold, N.; Steglich, W.; Metabolites of 2-Aminophenol from Fruit Bodies of Lepiota americana (Agaricales) Z. Naturforsch. C 55, 481-484, (2000) DOI: 10.1515/znc-2000-5-628

From the acetone extract of the North American toadstool Lepiota americana 2-aminophenoxazin-3-one (1) and a novel amino-1,4-benzoquinone derivative, lepiotaquinone (2), were isolated. The structure of 2 was confirmed by its preparation from 2-aminophenol and amino-1,4-benzoquinone.
Publikation

Schmidt, J.; Richter, K.; Voigt, B.; Adam, G.; Metabolic Transformation of the Brassinosteroid 24-Epi-castasterone by the Cockroach Periplaneta americana Z. Naturforsch. C 55, 233-239, (2000) DOI: 10.1515/znc-2000-3-415

After feeding of 24-epi-castasterone to the cockroach Periplaneta americana an organspecific epimerization of the brassinosteroid to 2,24-depi-castasterone could be detected in female insects. The metabolite being observed only in the ovaries and not in the testes of the insect was identified by GC/MS in comparison with a synthesized authentic sample. Contrary, 24-epi-brassinolide is not metabolized in the sexual organs of Periplaneta americana. This is the first evidence of a metabolic transformation of a brassinosteroid in insects.
Publikation

Porzel, A.; Phuong Lien, T.; Schmidt, J.; Drosihn, S.; Wagner, C.; Merzweiler, K.; Van Sung, T.; Adam, G.; Fissistigmatins A–D: Novel Type Natural Products with Flavonoid–Sesquiterpene Hybrid Structure from Fissistigma bracteolatum Tetrahedron 56, 865-872, (2000) DOI: 10.1016/S0040-4020(99)01049-2

From Fissistigma bracteolatum Chatt. (Annonaceae), a Vietnamese folk medicinal plant, the novel type natural products fissistigmatin A–D (1–4), being composed of a flavonoid and a sesquiterpene moiety, were isolated. Their structures were elucidated by extensive NMR techniques, MS, CD, molecular modelling calculations and X-ray analysis.
Publikation

Maier, W.; Schmidt, J.; Nimtz, M.; Wray, V.; Strack, D.; Secondary products in mycorrhizal roots of tobacco and tomato Phytochemistry 54, 473-479, (2000) DOI: 10.1016/S0031-9422(00)00047-9

Colonization of the roots of various tobacco species and cultivars (Nicotiana glauca Grah., N. longiflora Cav., N. rustica L., N. tabacum L., N. tabacum L. cv. Samsun NN, N. sanderae hort. Sander ex Wats.) as well as tomato plants (Lycopersicon esculentum L. cv. Moneymaker) by the arbuscular mycorrhizal fungus Glomus intraradices Schenck and Smith resulted in the accumulation of several glycosylated C13 cyclohexenone derivatives. Eight derivatives were isolated from the mycorrhizal roots by preparative high performance liquid chromatography (HPLC) and spectroscopically identified (MS and NMR) as mono-, di- and triglucosides of 6-(9-hydroxybutyl)-1,1,5-trimethyl-4-cyclohexen-3-one and monoglucosides of 6-(9-hydroxybutyl)-1,5-dimethyl-4-cyclohexen-3-one-1-carboxylic acid and 6-(9-hydroxybutyl)-1,1-dimethyl-4-cyclohexen-3-one-5-carboxylic acid. In contrast to the induced cyclohexenone derivatives, accumulation of the coumarins scopoletin and its glucoside (scopolin) in roots of N. glauca Grah. and N. tabacum L. cv. Samsun NN, was markedly suppressed.
Publikation

Lien, T. P.; Porzel, A.; Schmidt, J.; Van Sung, T.; Adam, G.; Chalconoids from Fissistigma bracteolatum Phytochemistry 53, 991-995, (2000) DOI: 10.1016/S0031-9422(99)00570-1

Phytochemical studies on the leaves of Fissistigma bracteolatum yielded besides the two known compounds 2-hydroxy-3,4,6-trimethoxychalcone (1) and 5,7,8-trimethoxyflav-3-ene (2), five new chalconoids 2-hydroxy-3,4,6-trimethoxychalcene (3), 2-hydroxy-3,4,6-trimethoxydihydrochalcone (4), 2′-hydroxy-3′,4′,6′-trimethoxydihydrochalcone (5), 2′-hydroxy-3′,4′,6′-trimethoxy-β′-methoxychalcane (6) and 2′-hydroxy-3′,4′,6′-trimethoxy-β′-ethoxychalcane (7). The structures of these compounds were determined by mass and NMR spectroscopic methods.
Publikation

Kobayashi, N.; Schmidt, J.; Nimtz, M.; Wray, V.; Schliemann, W.; Betalains from Christmas cactus Phytochemistry 54, 419-426, (2000) DOI: 10.1016/S0031-9422(00)00129-1

The presence of 14 betalain pigments have been detected by their characteristic spectral properties in flower petals of Christmas cactus (Schlumbergera x buckleyi). Along with the known vulgaxanthin I, betalamic acid, betanin and phyllocactin (6′-O-malonylbetanin), the structure of a new phyllocactin-derived betacyanin was elucidated by various spectroscopic techniques and carbohydrate analyses as betanidin 5-O-(2′-O-β-D-apiofuranosyl-6′-O-malonyl)-β-D-glucopyranoside. Among the more complex betacyanins occurring in trace amounts, the presence of a new diacylated betacyanin {betanidin 5-O-[(5″-O-E-feruloyl)-2′-O-β-D-apiofuranosyl-6′-O-malonyl)]-β-D-glucopyranoside} has been ascertained. Furthermore, the accumulation of betalains during flower development and their pattern in different organs of the flower has been examined.
Publikation

Irmler, S.; Schröder, G.; St-Pierre, B.; Crouch, N. P.; Hotze, M.; Schmidt, J.; Strack, D.; Matern, U.; Schröder, J.; Indole alkaloid biosynthesis in Catharanthus roseus: new enzyme activities and identification of cytochrome P450 CYP72A1 as secologanin synthase Plant J. 24, 797-804, (2000) DOI: 10.1111/j.1365-313X.2000.00922.x

The molecular characterization of CYP72A1 from Catharanthus roseus (Madagascar periwinkle) was described nearly a decade ago, but the enzyme function remained unknown. We now show by in situ hybridization and immunohistochemistry that the expression in immature leaves is epidermis‐specific. It thus follows the pattern previously established for early enzymes in the pathway to indole alkaloids, suggesting that CYP72A1 may be involved in their biosynthesis. The early reactions in that pathway, i.e. from geraniol to strictosidine, contain several candidates for P450 activities. We investigated in this work two reactions, the conversion of 7‐deoxyloganin to loganin (deoxyloganin 7‐hydroxylase, DL7H) and the oxidative ring cleavage converting loganin into secologanin (secologanin synthase, SLS). The action of DL7H has not been demonstrated in vitro previously, and SLS has only recently been identified as P450 activity in one other plant. We show for the first time that both enzyme activities are present in microsomes from C . roseus cell cultures. We then tested whether CYP72A1 expressed in E. coli as a translational fusion with the C . roseus P450 reductase (P450Red) has one or both of these activities. The results show that CYP72A1 converts loganin into secologanin.
  • Die Leibniz-Gemeinschaft
  • Digitalisierung in der Landwirtschaft
  • Martin-Luther Universität Halle
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