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91.
Jean-Jacques Vasseur Bernard Rayner Jean-Louis Imbach 《Journal of heterocyclic chemistry》1988,25(2):389-392
We have elucidated the exact mechanism of apurinic oligodeoxynucleotide d(Tp[AP]pT) cleavage by phenylhydrazine and shown that the final isolated product is in fact a 3-substituted derivative of 1-phenyl-pyrazole. 相似文献
92.
Absintholide is a new guaianolide dimer whose structure and stereochemistry has been elucidated on the basis of high resolution n.m.r. 相似文献
93.
94.
Paul Baret Eliezer Barreiro Andrew E. Greene Jean-Louis Luch Marco-Antonio Teixeira Pierre Crabbe 《Tetrahedron》1979,35(24):2931-2938
New allenic prostanoids 5c, d, 7,9c, and 15b have been prepared by total synthesis. In each case a cuprate-propargylic acetate reaction was used as the key step. 相似文献
95.
96.
A simplified procedure for the preparation of deoxynucleoside methyl- and arylphosphoramidites is described. Both types of phosphoramidites can be conveniently activated by N-methylaniline trifluoracetate for their use in oligodeoxynucleotide synthesis. 相似文献
97.
Jean-Louis Uribelarrea José Humberto De Queiroz Alain Pareilleux 《Applied biochemistry and biotechnology》1997,66(1):69-81
The aerobic growth ofSchizosaccharomyces pombe on mixtures of glucose and malate was investigated during continuous high cell density cultures with partial cell-recycle
using a membrane bioreactor. Determination of the specific metabolic rates relative to substrates and products allowed the
capacity of the yeast to metabolize malic acid under both oxidative metabolism (carbon limited cultures) and oxidofermentative
metabolism (carbon sufficient cultures) situations to be characterized. Under carbon limiting conditions, the specific rate
of malate utilization was dependent on the residual concentration and a limit for a purely oxidative breakdown without ethanol
formation was observed for a characteristic ratio between the rates of substrate consumption qm/qg of 1.63 g.g-1. In addition, the mass balance analysis revealed the incorporation of malic acid into biomass. In carbon excess environments,
the specific rate of malate utilization was dependent on both the residual malate and the specific rate of glucose consumption
indicating that in addition to its conversion into ethanol malate can be respiratively metabolized for qm/qg ratios higher
than 0.4 g.g-1. 相似文献
98.
Marcel Baiwir Gabriel Llabrs Lon Christiaens Jean-Louis Piette 《Magnetic resonance in chemistry : MRC》1981,16(1):14-16
The 77Se chemical shifts of 79 mono- or disubstituted benzo[b]selenophenes are reported. The results in the 2- and 3-substituted derivatives closely parallel those previously obtained in the corresponding selenophenes. The measured parameters also correlate well with those measured in benzo[b]tellurophenes. The 125Te and 77Se chalcogen nuclei appear to be much more sensitive to substituent effects than the more classical nuclei. The effects of Cr(acac)3, Eu(dpm)3 and concentration on the 77Se NMR spectra are briefly discussed. 相似文献
99.
Marie-Claire Lasne Jean-Louis Ripoll Jean-Claude Guillemin Jean-Marc Denis 《Tetrahedron letters》1984,25(35):3847-3848
5,6-dihydropyridine 1 is synthesized either by flash vacuum thermolysis of 1-azabicyclo[2.2.2] oct-2-ene 3 or by dehydrochlorination over solid bases of N-chloro-1,2,5,6-tetrahydropyridine 4 and characterized at low temperature by its 1H and 13C nmr and ir spectra. 相似文献
100.