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BIOLOGICAL ACTIVITIES OF PHTHALOCYANINES-X. SYNTHESES AND ANALYSES OF SULFONATED PHTHALOCYANINES 总被引:5,自引:0,他引:5
Hasrat Ali Réjean Langlois J. Richard Wagner Nicole Brasseur Benoit Paquette Johan E. VAN Lier 《Photochemistry and photobiology》1988,47(5):713-717
Abstract— Synthetic methods to obtain selectively sulfonated metallo phthalocyanines are compared. Both condensation and direct sulfonation procedures lead to mixtures of mono- to tetrasulfonated products which are resolved by reverse phase liquid chromatography in buffered aqueous-methanol. The proportion of sulfonated derivatives is examined as a function of the starting reagents in the case of the condensation method, and as a function of the temperature and reaction time in the case of the direct sulfonation procedure. The number of sulfonate groups per phthalocyanine molecule is determined by oxidative degradation of the phthalocyanine ring followed by quantitative chromatographic analysis of the sulfophthalamide and phthalamide fragments. 相似文献
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M Berger J Cadet R Berube R Langlois J E van Lier 《Journal of chromatography. A》1992,593(1-2):133-138
High-performance liquid chromatography-thermospray mass spectrometry was applied to the analysis of various radiation-induced decomposition products of thymidine including N-(2-deoxy-beta-D-erythro-pentofuranosyl)formamide and the various diastereomers of 5,6-dihydroxy-5,6-dihydrothymidine, 5-hydroxy-5,6-dihydrothymidine and 5,6-dihydrothymidine. This method combines high sensitivity and product resolution, rendering it particularly useful for monitoring the formation of radiation-induced base damage within DNA. 相似文献
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Under Lewis acid activation, hemiaminals of trifluoroacetaldehyde and related (fluoroalkyl)aldehydes generate iminium species that can react with various nucleophiles to provide fluorinated amines. 相似文献
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Robert WeavingEmmanuel Roulland Claude MonneretJean-Claude Florent 《Tetrahedron letters》2003,44(12):2579-2581
A synthesis of the alkylidene cyclopentenone prostaglandin TEI 9826 has been realized. The synthesis involved the preparation of the chiral 1,5-diene 8 using a stereoselective Claisen rearrangement from the allylic alcohol 6 giving the ester 7 after vinylation. Then a key RCM reaction allowed the preparation of the cyclopentenol 9 which, after oxidation, gave the cyclopentenone 10, precursor of the prostaglandin. 相似文献
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Provided that DMF (or another N,N-dialkylformamide) is present in the reaction medium, at least in a catalytic amount, fluoroform trifluoromethylates efficiently carbonyl compounds, even enolizable ones, when opposed to (TMS)(2)N(-) M(+), generated in situ from N(TMS)(3) and M(+) F(-) or RO(-) Na(+). When F(-) is used in a catalytic amount, silylated alpha-(trifluoromethyl)carbinols are obtained: in this case, the four-component system HCF(3)/N(TMS)(3)/catalytic F(-)/catalytic DMF behaves like the Ruppert's reagent, especially as far as nonenolizable carbonyl compounds are concerned (CF(3)SiMe(3) remains more efficient for enolizable carbonyl compounds). This process involves an adduct between DMF and (-)CF(3) which is the true trifluoromethylating agent. In the same way, fluoroform efficiently trifluoromethylates disulfides and diselenides when deprotonated with a strong base selected from t-BuOK or N(SiMe(3))(3)/Me(4)NF (or TBAT). t-BuOK is more adapted to the trifluoromethylation of aryl disulfides whereas N(SiMe(3))(3)/F(-) is well suited to that of aliphatic disulfides. 相似文献
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Nb-oxides and in the presence of acetic anhydride led to products , or with participation of the indole nucleus during the fragmentation reaction. 相似文献