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1.
Minor alkaloids isolated from the leaves and stems of Uncaria bernaysii F.v.M. (Rubiaceae) have been identified as tetrahydroalstonine, akuammigine and the N-oxides of the four stereoisomeric oxindole alkaloids isopteropodine, pteropodine, speciophylline and uncarine F. 相似文献
2.
Six isomers of the pentacyclic oxindoie alkaloid mitraphylline and five of their N-oxides have been identified as being present in the leaves of Uncaria longiflora (Poir.) Merr. Isomitraphylline and mitraphylline N-oxides have been prepared and characterized. 相似文献
3.
Nineteen indole alkaloids were isolated from Ghanaian Rauwolfia vomitoria leaves. The alkaloids comprised E-seco indole, sarpagan, picrinine, akuammiline, heteroyohimbine, oxindole, yohimbine and indolenine types. The biosynthetic relationship of the alkaloids is discussed. 相似文献
4.
Sarah R. Hemingway Peter J. Houghton J.David Phillipson Edward J. Shellard 《Phytochemistry》1975,14(2):557-563
Speciofoline has been assigned the epiallo B configuration on the basis of isomerization studies, NMR and CD spectra, and three new speciofoline isomers, mitrafoline (allo A), isomitrafoline (allo B) and isospeciofoline (epiallo A) have been isolated from Mitragyna speciosa Korth. Two new C-20 vinyl alkaloids, rotundifoleine and isorotundifoleine, have been separated as minor products from crystalline samples of rotundifoline and isorotundifoline respectively, previously isolated from M. parvifolia (Roxb.) Korth. A transient product observed during the isomerization of isorotundifoline has been identified as the pseudo B isomer, 3-epi-isorotundifoline. 相似文献
5.
Four isomeric oxindole alkaloids, isorhynchophylline, rhynchophylline, corynoxine and corynoxine B, have been isolated from the leaves of Uncaria macrophylla Wall. Corynoxine B has not previously been reported as a natural product. 相似文献
6.
7.
A new alkaloid roxburghine X, along with roxburghine D, formosanine and mitraphylline, has been isolated from the bark of Uncaria elliptica. Sitosterol, quinovaic acid, acetylquinovaic acid and scopoletin were isolated from the bark of Canthium dicoccum. 相似文献
8.
《Phytochemistry》1987,26(3):865-868
An oxindole alkaloid, Nb-demethylalstophylline oxindole has been isolated from the leaves of Alstonia macrophylla. Its structure has been elucidated on the basis of spectroscopic studies. 相似文献
9.
The structures of three new 11-monomethoxy pentacyclic oxindole alkaloids have been elucidated by chemical correlations with reserpinine: caboxine-A was assigned to the allo C19-méthyl α series: 3S, 4R, 7S, 19S; isocaboxine-A and B to the epi-allo C19-methyl α series and have, respectively, the following configurations 3R, 4S, 7S, 19S and 3R, 4S, 7R, 19S. 相似文献
10.
A verified sample of Uncaria callophylla was investigated for its alkaloid content. The stems provided mainly pseudoyohimbine and dihydrocorynantheine while the leaves furnished dihydrocorynantheine, gambirine and an unknown dimeric alkaloid probably derived from gambirine and pseudoyohimbine. 相似文献
11.
22 indole alkaloids were isolated from the stem bark of Nigerian Rauwolfia vomitoria and 20 characterized. The alkaloids comprised E-seco heteroyohimbine, sarpagan, dihydroindole, yohimbine and heteroyohimbine types. The biosynthetic relationship of the alkaloids is discussed. 相似文献
12.
Induction of alkaloid diversity in hybrid plant cell cultures 总被引:3,自引:0,他引:3
Yu. Sheludko I. Gerasimenko M. Unger I. Kostenyuk J. Stoeckigt 《Plant cell reports》1999,18(11):911-918
The treatment of Rauwolfia serpentina x Rhazya stricta somatic hybrid cell suspension culture with 100 μM of methyl jasmonate led to a general increase in indole alkaloid content and to qualitative changes in the alkaloid pattern.
The content of Six alkaloids were investigated with respect to their content in both the cell biomass and nutrition medium.
Intracellular 17-O-acetyl-norajmaline content on the 5th day after treatment had increased about 40-fold compared with the control culture.
The respective concentrations of the other alkaloids increased by a factor of two to five. In total 26 indole alkaloids were
identified in extracts of the methyl jasmonate-treated culture by TLC, UV, MS and NMR data and comparison with reference alkaloids.
The identification of macrophylline, yohimbine oxindole and yohimbine pseudoindoxyl has not been reported before in Rauwolfia serpentina or Rhazya stricta plants nor in cell cultures derived from these plants.
Received: 17 June 1998 / Accepted: 7 December 1998 相似文献
13.
The levels of alkaloids were determined in leaves and stems of 24 species of Heliotropium collected in Mexico and adjacent U.S.A. All species contained unsaturated pyrrolizidines, their content in leaves ranging from 0.003 to 0.18%. Saturated pyrrolizidine alkaloids were detected in nine species. Greenhouse-grown plants of five species had a significantly higher alkaloid content in their leaves than the corresponding field samples. In all these species, except for H. indicum, the differences were due to higher levels of saturated pyrrolizidines. 相似文献
14.
Fatimah Salim Mazatulikhma Mat Zain Mohd Syafiq Mohammad Ridzuan Moses K. Langat Dulcie A. Mulholland Rohaya Ahmad 《Phytochemistry letters》2013,6(2):236-240
A novel flavonoid, (?)-2R,3R-3,5,4′-trihydoxyflavan-[6,7:5″,6″]-2″-pyranone, named uncariechin (1), was isolated from the methanolic extract of the leaves of Uncaria longiflora var. pteropoda (Miq.) Ridsd. along with the known (?)-epiafzelechin (2) and (?)-epicatechin (3), methyl 4-hydroxybenzoate and 4-hydroxybenzaldehyde, four pentacyclic oxindole alkaloids, isopteropodine, pteropodine, uncarine F and isopteropodic acid, previously found in the stems, and two coumarins, scopoletin and 3,4-dihydroxy-7-methoxycoumarin. Structures of the compounds were elucidated by 1D and 2D NMR, FTIR, UV, MS, and experimental as well as calculated electronic circular dichroism (ECD) data. Compounds 2 and 3 were evaluated for their neurotoxic and neuroprotective properties against differentiated SH-SY5Y neuroblastoma cell lines using the MTS assay. Compounds 2 and 3 did not show any neurotoxic effects but showed strong protective potential against hydrogen peroxide-induced neurotoxicity with maximum cell viability at a concentration of 1 μM. 相似文献
15.
James P. Kutney Lewis S.L. Choi Pawel Kolodziejczyk Stephen K. Sleigh Kenneth L. Stuart Brian R. Worth W.G.W. Kurz K.B. Chatson F. Constabel 《Phytochemistry》1980,19(12):2589-2595
A detailed study of one cell line (coded as 943) of Catharanthus roseus cell cultures has revealed the presence of the following alkaloids: ajmalicine, vallesiachotamine, hörhammerinine, hörhammericine, vindolinine, 19-epi- vindolinine, 19-acetoxy-11-methoxytabersonine, 19-acetoxy-11 -hydroxytabersonine, 19-hydroxy- 11-methoxytabersonine, yohimbine and isositsirikine, together with dimethyltryptamine and a new strychnos-type alkaloid. 相似文献
16.
Trejo-Tapia G Sepúlveda-Jiménez G Trejo-Espino JL Cerda-García-Rojas CM de la Torre M Rodríguez-Monroy M Ramos-Valdivia AC 《Biotechnology and bioengineering》2007,98(1):230-238
Uncaria tomentosa cell suspension cultures were grown in a 2-L stirred tank bioreactor operating at a shear rate gamma(.)(avg)=86 s(-1). The cultures showed an early monophasic oxidative burst measured as H2O2 production (2.15 micromol H2O2 g(-1) dw). This response was followed by a transient production of monoterpenoid oxindole alkaloids (178 +/- 40 microg L(-1) at 24 h). At the stationary phase (144 h), the increase of the shear rate gamma(.)(avg) up to 150 s(-1) and/or oxygen tension up to 85% generated H2O2, restoring oxindole alkaloid production. U. tomentosa cells cultured in Erlenmeyer flasks also exhibited the monophasic oxidative burst but the H2O2 production was 16-fold lower and the alkaloids were not detected. These cells exposed to H2O2 generated in situ produced oxindole alkaloids reaching a maximum of 234 +/- 40 microg L(-1). A positive correlation was observed between the oxindole alkaloid production and the endogenous H2O2 level. On the other hand, addition of 1 microM diphenyleneiodonium (NAD(P)H oxidase inhibitor) or 10 microM sodium azide (peroxidases inhibitor) reduced both H2O2 production and oxindole alkaloids build up, suggesting that these enzymes might play a role in the oxidative burst induced by the hydrodynamic stress. 相似文献
17.
α,β-Dipyridyl isolated from Nicotiana tabacum plants which had been fed anatabine-[2′-14C, 13C], and then allowed to dry in air for 20 days was radioactive (82% specific incorporation)An examination of its 13C NMR spectra established that it was enriched only at C-2, indicative of its direct formation from anatabineThe labelled anatabine was also fed to Nglauca and Nglutinosa plants, which were extracted immediately after harvestingIn these experiments no radioactive α,β-dipyridyl was detected, suggesting that α,β-dipyridyl is an artifact produced by the oxidation of anatabine in the drying leaves of tobaccoAnabasine isolated from the Nicotiana species which had been fed anatabine-[2′- 14C, 13C] was unlabelled, indicating that none of this alkaloid is formed by the reduction of anatabine. 相似文献
18.
A series of cinchona alkaloid derivatives were used to catalyze the asymmetric anti‐Mannich‐type reaction of 3‐methyl‐2‐oxindole with N‐tosyl aryl aldimines. The resulting anti‐3,3‐disubstituted 2‐oxindole products were obtained in good yields (up to 92%) with high diastereo‐ and enantioselectivities (anti/syn up to 97:3 and 91% ee). Chirality 26:801–805, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
19.
Gabriela?R.?Luna-Palencia Ariana?A.?Huerta-Heredia Carlos?M.?Cerda-García-Rojas Ana?C.?Ramos-Valdivia
The alkaloids of Uncaria tomentosa micropropagated plantlets and root cultures were isolated and identified by NMR and mass spectrometry. Plantlets yielded pteropodine (1), isopteropodine (2), mitraphylline (3), isomitraphylline (4), uncarine F (5), speciophylline (6), rhynchophylline (7) and isorhynchophylline (8). In plantlets growing under continuous light, tetracyclic alkaloids 7 and 8 decreased from 20 ± 1.8 at 2 months to 2.2 ± 0.33 mg/g dry wt at 6 months, while the pentacyclic alkaloids 1–4 increased from 7.7 ± 1.4 to 15 ± 0.05 mg/g dry wt, supporting their biogenetic conversion. Micropropagated plantlets produced four times more alkaloids (27.6 ± 3.1 mg/g dry wt) than greenhouse plants. Plantlet roots yielded 3, 4, 8 and the glucoindole alkaloids 3α-dihydrocadambine (9) and dolichantoside (10), the last one not previously found in Uncaria. 相似文献
20.
S. Thiyagarajan M. Arumugam N. Senthil S. Vellaikumar S. Kathiresan 《Biotechnology letters》2018,40(3):577-584