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应用球面对称设计研究了水/有机溶剂两相体系对嘧啶核苷磷酸化酶基因工程菌生物转化合成5-氟尿苷的影响。结果表明,以30%(体积分数)DMSO为有机溶剂,当其体积比(以反应物总体积计)为30%、反应温度为55℃、反应时间为1 h、装液量为4 mL/50 mL时,5-氟尿嘧啶的转化率达75.7%,5-氟尿苷产量较单水相时提高... 相似文献
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1尿苷(Uridine)尿苷(Uridine)由名尿嘧啶核苷,由尿嘧啶与核糖(呋喃核糖)环组成,系核苷类的一种,在动物体中广泛存在,在人体血液中有一定浓度,在中药泽泻中也有游离的尿苷存在。现尿苷可由合成法制取。化学结构如下:1.1理化性质尿苷为白色针状结晶或粉末,熔点167.2℃,无气味,味稍甜而微辛。能溶于水,每毫升可溶解0.05 g,微溶于稀醇,不溶于无水乙醇。尿苷的CAS号为58-96-8。 相似文献
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目的探讨尿苷二磷酸(Uridine diphosphate,UDP)与尿苷三磷酸(Uridine triphosphate,UTP)两种佐剂对HAV抗原和HBsAg诱导小鼠体液免疫应答的影响。方法分别在HBsAg(1μg)和HAV抗原(18 EU)中加入不同浓度的UDP和UTP(HBsAg组:UDP和UTP均500μg及1、2、5、10 mg,HAV抗原组:UDP和UTP均500μg及1、2 mg),均经腹部皮下多点注射免疫ICR小鼠(HBsAg组:2针,间隔2周,0.1 ml/只;HAV抗原组:单针免疫,0.2 ml/只),并设空白对照组(生理盐水100μl)、抗原组对照组(HBsAg 1μg;HAV抗原18 EU)、铝佐剂组对照组(铝佐剂300μg)、UDP+铝佐剂复合组(HBsAg 1μg+铝佐剂300μg+UDP 2 mg;HAV 18 EU+铝佐剂300μg+UDP 2 mg)和UTP+铝佐剂复合组(HBsAg 1μg+铝佐剂300μg+UTP 2 mg;HAV 18 EU+铝佐剂300μg+UTP 2 mg),分别于末次免疫后(HBsAg组:第4、8、12和16周;HAV抗原组:第4、8、12周)采血,分离血清,ELISA法检测小鼠血清中抗-HBsAg IgG和抗-HAV IgG水平。免疫18周后,分别取HBsAg组中UDP和UTP最佳浓度组及空白对照组小鼠心脏、肝脏、脾脏、肾脏及肺组织进行病理观察。结果除空白对照组小鼠血清检测不到抗-HBsAg IgG外,其余各组小鼠血清抗-HBsAg IgG及抗-HAV IgG水平均在第8周达到峰值,以后逐渐下降。末次免疫后,UDP及UTP各组抗-HBsAg IgG及抗-HAV IgG水平均高于抗原对照组,差异均有统计学意义(P均<0.05)。HBsAg组UDP+铝佐剂复合组产生的IgG水平明显高于抗原对照组、铝佐剂对照组及UDP和UTP各浓度组(P<0.05);HAV抗原组UTP+铝佐剂复合组产生的IgG水平明显高于抗原对照组、铝佐剂对照组及UDP和UTP各浓度组(P<0.05)。在两种抗原中,UDP和UTP的最佳浓度均为2 mg/只。在设置的浓度范围内,UDP和UTP佐剂均未观察到毒性反应。结论UDP和UTP均能明显增强HBsAg及HAV抗原诱导小鼠的体液免疫应答。 相似文献
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《中国生物制品学杂志》2013,(11)
目的建立测定半夏提取物中尿苷含量的超高效液相色谱(ultra performance liquid chromatography,UPLC)法,并进行验证,同时对半夏不同提取工艺的尿苷含量进行比较。方法应用UPLC法测定尿苷对照品溶液、供试品溶液中尿苷的含量,并对方法的线性、精密度、稳定性、重复性、准确性进行验证。采用建立的方法检测传统水提醇沉工艺及隔膜压滤工艺半夏提取物中尿苷含量。结果半夏提取物中尿苷在0.411 620.58μg/ml浓度范围内,与峰面积呈良好的线性关系(r=0.999 9);用建立的方法连续进样6次,检测对照品溶液中尿苷含量,RSD=0.32%;室温下放置8 h,检测对照品中尿苷含量,RSD=0.23%;隔膜压滤工艺半夏提取液取6份进样,检测的尿苷平均含量为0.016%,RSD=0.65%;9份隔膜压滤工艺半夏提取液的平均加标回收率为99.25%,RSD=1.06%。隔膜压滤工艺的指纹图谱特征峰数目多于传统水提醇沉工艺,核苷类成分的含量也明显高于水提醇沉工艺;隔膜压滤工艺中尿苷含量为传统水提醇沉工艺的13倍。结论建立了检测半夏提取物中尿苷含量的UPLC法,该方法精密度、稳定性、重复性及准确性好,为科学有效控制半夏药材及饮片的质量提供了参考。 相似文献
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司他呋啶(2′,3′-双脱氢-3′-脱氧胸苷,d4T)是抑制HIV逆转录酶的抗病毒药物.对多年来有关d4T的合成方法进行了综述.合成d4T主要有两大合成路线,一条是以β-胸苷为原料,另一条是以5-甲基尿苷为原料,对各条路线的优缺点进行了评述. 相似文献
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The pure mononitro derivative of benzimidazolone-2 can be obtained only when the nitration reaction is carried out in mild conditions, otherwise di-, tri- and tetranitro derivatives are also formed. The results of our studies derived optimum conditions for the nitration process necessary to obtain pure 5-nitrobenzimidazolone-2. 相似文献
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M. Kamel I. B. Hannout M. A. Allam A. T. Al Aref A. Z. Morsi 《Advanced Synthesis \u0026amp; Catalysis》1970,312(5):737-743
Both 5-aminobenzothiophene and 5-aminobenz-1,2,3-thiadiazole condense readily with 2,4-dinitrochlorobenzene to give dinitroanilino derivatives which provide after partial reduction the aminonitroanilino derivatives. Treatment of these o-diamines with the proper reagents affords triazole and imidazole derivatives. Oxidation of 4-arylazo-5-aminobenzothiophene or benz-1,2,3-thiadiazole yields the corresponding triazole derivatives. 相似文献
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The behavior of copper-, iron- and cobalt-exchanged ZSM-5 (Si/Al = 20) and bimetallic forms of the same zeolite was investigated with reference to the adsorption of N2O and CO at 303 K. The interactions of both gases with investigated zeolites have been studied using microcalorimetry and infrared spectroscopy. The values of differential heats of adsorption and the amounts of adsorbed gases were determined. Both gases react with the charge-balancing cations as active sites for adsorption. CuZSM-5 shows significantly better performances than FeZSM-5 and CoZSM-5, toward both gases; additionally, nitrous oxide can be chemisorbed on CuZSM-5. Adsorption capabilities of FeZSM-5 and CoZSM-5 are increased with the addition of copper ions. The heats of CO interaction with copper-containing samples have been found to be higher then the heats of N2O interaction, while for FeZSM-5 and CoZSM-5 samples similar heats were detected for both gases. In the case of CuZSM-5, as a result of competitive adsorption between previously adsorbed N2O and incoming CO from the gas phase, a surface reaction is found. 相似文献
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《Inorganic chemistry communications》2007,10(7):743-747
The reaction of ferrocenyllithium (FcLi, 1) with dimethyl or diethylaluminum chloride affords known mixed dimers 2 built from dialkyl(ferrocenyl))aluminium and dialkylaluminum chloride and also, depending on the reaction conditions, the unknown dimers from dialkyl(ferrocenyl)aluminum 3, of which the dimethyl derivative could be isolated in a pure state and characterised by X-ray structural analysis. The ferrocenyl group occupies the bridging position and there is a centre of inversion. The solution-state structures were determined by NMR spectroscopic methods (1H, 13C, 27Al NMR). The gas-phase structure of monomer FcAlH2 3(M) was optimised at the B3LYP/6-311 + G(d,p) level of theory. 相似文献
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以二茂铁甲醛和对甲苯磺酰基异氰(TOSMIC)为原料,经过Van Leusen反应,一步合成目标化合物5-二茂铁基噁唑,通过~1HNMR、~(13)CNMR和ESI-MS对其结构进行表征,并对影响收率的主要因素进行考察。结果表明,在物料比n(TOSMIC)∶n(二茂铁甲醛)为1.1∶1、反应溶剂为甲醇、K_2CO_3用量即n(K_2CO_3)∶n(二茂铁甲醛)为2.0∶1、反应温度为65℃、反应时间为8 h的最佳条件下,目标化合物收率达到74.7%。该方法具有原料廉价易得、反应操作简单、收率高等优点,具有一定的应用价值。 相似文献