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48 1 Vol. 48 No. 1
2018 2 Feb 2018

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8-(li)ĺϳо
־*OV ϹI(y)W(xu) W(xu)ch(hun)W(xu)Ժ 450001
ժҪԲAԭϳgw7-y߻^(gu)7-c-ʻl(f)ɻȡõ4N8-(li)YM(jn)˱˴߻܄wϵضȵ،a(chn)ƷʵӰ(yu)l飺߻y20%n7-򣩡n^(gu)⛣= 1.02.0܄棯ˮض100(yu)lĿ˻1 Ŀʞ54.5%~59.2%
P(gun)I~8-(li)A13-׻-7--8-S-ʻ
ЈD(li)̖TQ464īIRaA¾̖1009-9212201802-0035-03
Synthesis of 8- Substituted Acyl Caffeine Analogues
GUO Sheng-li, LI Zhi-cheng*, SUN Gang-chun (College of Chemistry, Chemical and Environmental Engineering, Henan University of Techonology, Zhengzhou 450001, China)
Abstract1,3-Dimethyl-7-alkylxanthine was prepared from theophylline and alkyl bromide. Using AgNO3 as catalyst and K2S2O8 as oxidant, 8-substituted acyl caffeine analogues were synthesized via free radical reaction between 1,3-dimethyl-7-alkylxanthine and -oxo carboxylic acid. Their structures were characterized using 1H NMR and 13C NMR. The factors influencing the yield of the reaction were studied. The optimum reaction conditions were as following: the amount of catalyst of 20%, 1.02.0 as the ratio of n(7-butyl caffeine)/n(K2S2O8), a mixture of CH3CN and H2O as reaction solvent and reaction temperature of 100. The total yield of the target product was up to 54.5%~59.2%.
Key words8-substituted acyl caffeine analogue; theophylline; 1,3-dimethyl-7-butyl-8-acetylxanthine; -oxo carboxylic acid
ĿȻƌW(xu)Ŀ21302042ʡƼP(gun)ӋĿ162102210040
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ոڣ2018-02-10
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