Zobrazeno 1 - 10
of 61
pro vyhledávání: '"D.E.U. Ekong"'
Publikováno v:
Journal of the Chemical Society, Perkin Transactions 1. :727
The residual uncertainty in the structure of euphorianin, an ingol diterpenoid from the latex of Euphorbia poisonii, has been resolved by nuclear Overhauser enhancement difference experiments which revealed the configuration at C-19 to be S. The 1H a
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::492d9447c857c037ac3f2e2ab651d9ae
https://doi.org/10.1039/p19900000727
https://doi.org/10.1039/p19900000727
Autor:
Koji Nakanishi, Joseph I. Okogun, Clayton Natta, V. U. Enyenihi, D.E.U. Ekong, Valeria Balogh-Nair
Publikováno v:
Nature. 258:743-746
RECENT efforts to develop therapeutic agents for the treatment of sickle cell disease have led to the discovery of several antisickling agents1. We now report a new such agent, 3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-6-butyric acid (DBA) (Compound 1
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::88264efa86a718f577bb515f5bb33bfe
https://doi.org/10.1038/258743a0
https://doi.org/10.1038/258743a0
Publikováno v:
Tetrahedron. 34:1221-1224
During the determination of the constitution of ekersenin isolated from Ekererbegia senegalensis , eight isomeric monomethoxy-monomethylcoumarins were synthesised. These studies proved that ekersenin was 4-methoxy-5-methylcoumarin, a constitution wit
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::4e4c6717a56f3c6f02417b5b90a99ae9
https://doi.org/10.1016/0040-4020(78)80149-5
https://doi.org/10.1016/0040-4020(78)80149-5
Autor:
Gerhard G. Habermehl, D.E.U. Ekong, Hans Jörg Lindner, Christopher O. Fakunle, Joseph I. Okogun
Publikováno v:
Zeitschrift für Naturforschung B. 42:243-247
The conversion of euphorianin to deacetyldehydroeuphorianin which was used in an X-ray crystal structure analysis is described. A new pentacyclic structure related to ingol tetraacetate is described for euphorianin.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::29773c98f337b99b601321dcb36c4fd8
https://doi.org/10.1515/znb-1987-0221
https://doi.org/10.1515/znb-1987-0221
Publikováno v:
Chemical Geology. 27:11-28
Crude-oil samples from three oilfields in the east and west of the Tertiary Niger delta, Nigeria, were analysed for pentacyclic triterpanes by gas chromatography and gas chromatography—mass spectrometry. Previously identified pentacyclanes such as
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::7c663b411e144e677dcb312c1f7c840f
https://doi.org/10.1016/0009-2541(79)90100-1
https://doi.org/10.1016/0009-2541(79)90100-1
Publikováno v:
Chemical Geology. 27:29-37
Immature shale of the Agbada Formation of the Tertiary Niger delta, Nigeria, cored at various depths A simulation experiment carried out by heating the immature shale at 300°C in vacuo (0.4 Torr) for ten days resulted in a triterpane composition sim
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::e1a433c64108ab79eeb38e1ef09e6975
https://doi.org/10.1016/0009-2541(79)90101-3
https://doi.org/10.1016/0009-2541(79)90101-3
Publikováno v:
Journal of Geochemical Exploration. 15:653-662
Ekweozor, CM., Okogun, J.I., Ekong, D.E.U. and Maxwell, J.R., 1981. C 24 –C 27 degraded triterpanes in Nigerian petroleum: Novel molecular markers of source/input or organic maturation? In: A.W. Rose and H. Gundlach (Editors), Geochemical Explorati
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::2adcfbfbe7726d467592217002e8a4b5
https://doi.org/10.1016/0375-6742(81)90095-9
https://doi.org/10.1016/0375-6742(81)90095-9
Publikováno v:
J. Chem. Soc., Perkin Trans. 1. :2118-2122
The residues collected after isolation of anthothecol from Khaya anthotheca have afforded a new meliacin for which the structure (2b)(11β-acetoxyazadirone) is proposed. In addition, deacetylanthothecol and a sterol mixture shown by g.l.c. to consist
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::7b37529b6c785400981bc10a3dd94e59
https://doi.org/10.1039/p19750002118
https://doi.org/10.1039/p19750002118
Publikováno v:
Biochemie und Physiologie der Pflanzen. 174:51-57
Summary A comparative study of some of the hormones in acidic extracts obtained from fruits of cowpea was undertaken in relation to premature fruit abscission. Extracts were obtained from 6-day and 2-day old fruits from the lowest and upper racemes o
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::67b334680d00bcb53ea7083ec22c966c
https://doi.org/10.1016/s0015-3796(17)30546-2
https://doi.org/10.1016/s0015-3796(17)30546-2
Publikováno v:
Phytochemistry. 19:223-225
Abscisic acid, phaseic acid and 4′-dihydrophaseic acid were identified by GC-MS of derivatized (Me, MeTMSi) extracts from immature fruits of Vigna unguiculata. The fruits also contained some other ABA-related compounds, one of which might be epi-4
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::bc1204b02dfad08d2b1133896d3a7aa4
https://doi.org/10.1016/s0031-9422(00)81965-2
https://doi.org/10.1016/s0031-9422(00)81965-2