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21.
Yuri N. Utkin Yasumaru Hatanaka Peter Franke Jan Machold Ferdinand Hucho Victor I. Tsetlin 《Journal of Protein Chemistry》1995,14(4):197-203
Five singly modified nitrodiazirine derivatives of neurotoxin II (NT-II) fromNaja naja oxiana were obtained after NT-II reaction with N-hydroxysuccinimide ester of {2-nitro-4 [3-(trifluoromethyl)-3H-diazirin-3yl]phenoxy}acetic acid followed by Chromatographic separation of the products. To localize the label positions, each derivative was first UV-irradiated and then subjected to reduction, carboxymethylation, and trypsinolysis. Tryptic digests were separated by reversed phase-HPLC, the labeled peptides being identified by mass spectrometry. The derivatives containing the photolabel at the position Lys 25, Lys 26, Lys 44, or Lys 46 were [125I]iodinated by the chloramine T procedure. Each iodinated derivative was found to form photoinduced cross-links with the membrane bound nicotinic acetylcholine receptor (AChR) fromTorpedo californica. The pattern of labeling the receptor's, , , or subunits was dependent on the photolabel position in the NT-II molecule and differed from that obtained earlier with an analogous series ofp-azidobenzoyl derivatives of NT-II. The results obtained indicate that (i) different sides of the neurotoxin molecule are involved in the AChR binding, and (ii) fragments of the different AChR subunits are located close together at the neurotoxin-binding sites.Abbreviations AChR
Acetylcholine receptor
- NDPA
[2-nitro-4-[3-(trifluoromethyl)-3H-diazirin-3-yl]]phenoxy]acetyl
- NT-II
neurotoxin II 相似文献
22.
Ferdinand Bohlmann Pahup Singh Jasmin Jakupovic Robert M. King Harold Robinson 《Phytochemistry》1982,21(2):371-374
An investigation of the aerial parts of Chromolaena chasleae afforded a prostaglandin-like acid, whose structure followed from the 1H NMR spectral data and from the reaction with periodate, which afforded a hemiacetal. From a new Chromolaena species, three novel cadinene derivatives were isolated, which were closely related to those isolated previously from this genus. 相似文献
23.
Ferdinand Bohlmann Wolfgang Kramp Jasmin Jakupovic Harold Robinson Robert M. King 《Phytochemistry》1982,21(2):399-403
The aerial parts of Baccharis minutiflora afforded in addition to known compounds eight new ent-kaurane derivatives, one being a homo kaurane, while the aerial parts of B. alatemoides gave two pairs of epimeric clerodane derivatives, which, however, had to be modified chemically before they could be separated. The stereochemistry of these diterpenes could not be elucidated with certainty. 相似文献
24.
Ferdinand Bohlmann Maniruddin Ahmed Harold Robinson Robert M. King 《Phytochemistry》1982,21(7):1675-1678
The investigation of the aerial parts of a variety of Enhydra fluctuans afforded in addition to 4-hydroxyfarnesyl acetate and fluctuadin five new melampolides elucidated by high field 1H NMR spectroscopy. The chemotaxonomic situation is discussed briefly. 相似文献
25.
Ferdinand Bohlmann Naleen Borthakur Robert M. King Harold Robinson 《Phytochemistry》1982,21(7):1793-1794
Calea reticulata afforded in addition to known compounds two new sesquiterpenes. These were germacrane and eudesmane derivatives, identified as germacra-4(15),5,10(14)-trien-1-one and 6-epi-β-verbesinol coumarate, respectively. 相似文献
26.
Ferdinand Bohlmann Rajinder K. Gupta Robert M.^King Harold Robinson 《Phytochemistry》1982,21(10):2593-2595
Calea villosa afforded three new sesquiterpene lactones, two furanoheliangolides and an epoxy- germacranolide, as well as several known compounds. The structures were elucidated by spectroscopic methods. 相似文献
27.
Ferdinand Bohlmann Maniruddin Ahmed Jasmin Jakupovic Robert M. King Harold Robinson 《Phytochemistry》1982,21(3):691-694
An investigation of Brickellia diffusa afforded three new dehydronerolidol derivatives and five new labdane derivatives, all highly oxygenated. The structures were elucidated by spectroscopic methods and a few chemical transformations. The compounds isolated showed close relationships to those isolated from Brickellia sp. 相似文献
28.
Ferdinand Bohlmann Alfons Adler Jasmin Jakupovic Robert M. King Harold Robinson 《Phytochemistry》1982,21(6):1349-1355
The investigation of two Mikania species, both previously placed in the genus Kanimia, afforded in addition to known compounds several new germ 相似文献
29.
Ferdinand Bohlmann Naleen Borthakur Jasmin Jakupovic Joachim Pickard 《Phytochemistry》1982,21(6):1357-1360
An investigation of Ursinia saxatilis afforded in addition to known compounds a new eudesmanolide derived from ursialpinolide, a germacranolide rel 相似文献
30.
Hypochoeris cretensis afforded, in addition to triterpenes and isoalantolactone, a new guaian-5, 12-olide and the corresponding precursor. 相似文献