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本文用自旋捕捉-ESR技术研究了二茂戊铁、环二烯和胺甲基类取代二茂铁的紫外光解过程中的活泼自由基。结果表明,二茂铁光解初级过程中生成的自由基为(C_5H_5Fe)·和C_5H_5·,其衍生物光解则生成(C_5H_5Fe)·和RC_5H_4·,而(C_5H_5Fe)·还可以进一步分解给出C_5H_5和Fe。 相似文献
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稀土元素对腺嘌呤及鸟嘌呤单核苷酸的水解断裂作用 总被引:2,自引:0,他引:2
本文研究稀土元素对5'-腺嘌呤核苷酸(5'-AMP)和5'-鸟嘌呤核苷酸(5'-GMP)的水解断裂作用。空气中CeCl~3在pH 9,37℃能有效地水解断裂5'-AMP及5'-GMP,而其它三价稀土对5'-AMP和5'-GMP的水解断裂作用很小, 铈对5'-AMP的水解断裂速度大于5'-GMP。紫外吸收光谱实验结果表明反应体系中Ce(Ⅲ)部分被氧化成Ce(Ⅳ), Ce(Ⅳ)的氢氧簇合物是使5'-AMP和5'-GMP水解的活性组分。 相似文献
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本文报道了五个新的一茂二元羧酸镱的合成:o-C_6H_4(COO)_2YbC_5H_5(1),(CH_2COO)_2YbC_5H_5(2),(CHCOO)_2YbC_5H_5(3),CH_3(COO)_2YbC_5H_5(4),(COO)_2YbC_5H_5(5),这些络合物均经元素分析和红外光谱鉴定。可能由于这些络合物具有螯合环的结构,所以它们在空气中的隐定性较强。 相似文献
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5-硝基-2H-四唑的合成、反应性及产物晶体结构的研究 总被引:1,自引:0,他引:1
5-氨基四唑(1)经过重氮化反应得到5-硝基四唑(5),5与甲醛反应得到2-羟甲基-5-硝基四唑(6),6与HCl或HBr反应分别得到5-5氯代四唑(7)和5-溴代四唑(8),采用MS,IR,1H NMR,13C NMR等技术对这些化合物进行了表征.用X射线单晶衍射法测定了化合物5-硝基四唑钠(4),5和6的晶体结构.化合物4属于三斜晶系,P-1空间群;化合物5和6均属于单斜晶系,P21空间群,化合物6的晶胞参数a=0.66131(18)nm,b=0.54905(15)nm,c=0.7566(2)nm,Z=2,V=0.27470(13)nm3,Dc=1.754g/cm3,F(000)=128,μ=0.160mm-1. 相似文献
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以取代苯甲醛为原料,经Wittig反应、水解反应和NaBH4还原反应制得5个取代苯乙醇衍生物(4a~4e);以4a~4e和其他芳乙醇(4f~4r)为原料,依次与全乙酰化溴代葡萄糖经Koenigs-Knorr偶联和MeONa/MeOH脱除乙酰保护基,合成了18个取代苯乙醇葡萄糖氧苷类似物(5a~5r,其中5b~5r为新化合物),其结构经1H NMR和HR-MS(ESI)表征。采用MTT法研究了5a~5r对缺氧损伤的内皮细胞(EA.hy926)代谢活力的影响。结果表明:5e, 5g, 5m, 5p, 5q和5r对EA.hy926的保护作用优于红景天苷。 相似文献
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以取代苯甲醛(1a~1t)为原料,通过Knoevenagel缩合、酯化和LiAlH4还原等反应制得苯丙烯醇衍生物(3a~3t);以取代肉桂醛(1u~1x)为原料,经NaBH4还原制得苯丙烯醇衍生物(3u~3x); 3a~3x与全乙酰化溴代葡萄糖经Koenigs-Knorr偶联反应及MeONa/MeOH体系脱除乙酰保护基反应,合成了24个苯丙烯类葡萄糖氧苷(5a~5x),其中5c,5f ~ 5x为新化合物,其结构经1H NMR和ESI-MS表征。采用MTT法测定了5对缺氧损伤的内皮细胞(EA.hy926)的抗缺氧活性。实验结果表明: 5b, 5e, 5g, 5p, 5q, 5s, 5t和5y对EA.hy926的抗缺氧活性均高于经景天苷。 相似文献
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5-Fluorouracil (5-Fu,1)1 is an important antitumor drug. Some derivatives2,3 have shown better therapeutic efficacy than 5-Fu. In order to find much more better antitumor drugs of its derivatives, several attempts have been made and many different types of its derivatives have been prepared at N1, N3 position4~7. Moreover, several different ways have been used for alkylation of 5-Fu7~10. However, up to now, the arylation of 5-Fu at N1 or N3 position hasn't been reported, and the compound o… 相似文献
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含5-氟尿嘧啶的氨基酸衍生物的合成及其抗肿瘤活性研究 总被引:2,自引:0,他引:2
5-氟尿嘧啶乙酸对硝基苯酯和5-氟尿嘧啶丙酸对硝基苯酯与一系列氨基酸反应,制备了12个新的含5-氟尿嘧啶的氨基酸衍生物,并确定了化合物的结构。初步动物试验表明某些化合物有一定的抗肿瘤活性。 相似文献
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As an antitumor drug, because of its low efficacy and high toxicity, several modifications have been made on 5-fluorouracil (5-Fu). Some compounds have been found to be highly efficient and much less toxic for the treatment of various solid tumors1~4. Among them, deoxyfluridine (Furtulon) has been used clinically for several years. In our previous work, we have prepared several substituted derivatives of 5-Fu and the primary result shows that some of them have certain antitumor activity5,6. … 相似文献
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合成了9个新的5-氟脲嘧啶自旋标记衍生物2、5a-c和7a-c,经元素分析、IR、UV、MS和ESR确定了其组成和结构,对化合物2和5a-c进行了抗小艾氏腹水肉瘤S180的体内筛选,初步试验结果表明:化合物5c对两种瘤株均显示较强的抑制作用,其抗肿瘤活性与5-氟脲嘧啶相似,而5c(LD50=944.8mg/kg)的急性毒性比5-氟脲嘧啶(LD50=117.2mg/kg)降低约8倍。 相似文献
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A new series of N^1-acetylamino-(5-alkyl/aryl- 1,3,4-thiadiazole-2-yl)-5-fluorouracil derivatives were designed and synthesized. These compounds have not been reported in literature, and their structure chemical were confirmed by IR, ^1H NMR and MS (HRMS). The results of antitumor inhibitory activity test showed that some compounds possess more potent antitumor inhibitory activity than 5-fluorouracil. 相似文献
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A new series of N1-acetylamino-(5-alkyl/aryl- 1,3,4-thiadiazole-2-y1)-5-fluorouracil derivatives were designed and synthesized.These compounds have not been reported in literature,and their structure chemical were confirmed by IR,1H NMR and MS (HRMS).The results of antitumor inhibitory activity test showed that some compounds possess more potent antitumor inhibitory activity than 5-fluorouracil. 相似文献
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Lolita Caram Mech Doeleman William J. Roberts Richard J. Prankerd John H. Perrin William J. Underberg Kenneth B. Sloan 《Journal of heterocyclic chemistry》1999,36(2):397-401
4′-Substituted 1-arylcarbonyl-5-fluorouracil derivatives were synthesized from the reaction of the potassium salt of 5-fluorouracil with one equivalent of aryl acid chloride in acetonitrile. 4′-Substituted 3-arylcar-bonyl-5-fluorouracil derivatives were synthesized from the reaction of 5-fluorouracil with 3 equivalents of the aryl acid chloride in pyridine and the subsequent hydrolysis of the 1,3-diarylcarbonyl-5-fluorouracil derivatives in situ with a small amount of water. If a large amount of water were used in the second step, the 1,3-diarylcarbonyl-5-fluorouracil precipitated before it hydrolyzed. The melting behaviors of both the 1-arylcarbonyl-5-fluorouracil and 3-arylcarbonyl-5-fluorouracil series suggested that thermal decomposition or rearrangement occurred on heating. The position of the C6-H absorption in the 1H nmr spectra of 1-arylcarbonyl-5-fluorouracils was 0.14 to 0.23 ppm farther downfield than that of the corresponding 3-arylcarbonyl-5-fluorouracils while that of the 1,3-diarylcarbonyl-5-fluorouracils was even farther downfield. The Rf values of 1-arylcarbonyl-5-fluorouracils were significantly greater (0.23 to 0.41) than those of the corresponding 3-arylcarbonyl-5-fluorouracils, while that of 1,3-diarylcarbonyl-5-fluorouracil was slightly greater than that of 1-arylcarbonyl-5-fluorouracils. 相似文献
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Alkylation of trimethylsilyl derivatives of uracil, thymine, 5-fluorouracil, and 6-methyluracil with propargyloxymethyl chloride afforded the corresponding 1-(propargyloxymethyl) derivatives, new unsaturated acyclic nucleosides having an end carbon-carbon triple bond.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 797–799, June, 1993. 相似文献
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Synthesis of a New Series of Bone Affinity Compounds 总被引:3,自引:0,他引:3
Ying WANG Hong CHEN Zong Ming WAN Mao Sheng CHENG Xue Chao WANG Guo Liang CONG Sheng JING Zi Ping YAN Bo WU 《中国化学快报》2006,17(3):310-312
As known that tetracycline possesses bone affinity1, which can be used as carrier of bone-targeting drugs. Chrysophanol is one of the anthraquinone components isolated from Rheum palmatum L., its structure is similar to tetracycline. The bone affinity of … 相似文献