4-硝基苯基马来酰亚胺的合成研究

以顺丁烯二酸酐和对硝基苯胺为原料,甲苯和DMF混合溶液作溶剂,对甲基苯磺酸和硫酸铜为催化剂,采用两步法合成了4-硝基苯基马来酰亚胺,用红外光谱和核磁共振氢谱对产物进行了表征;同时研究了反应物物质的量比、催化剂用量以及混合溶剂配比等因素对合成4-硝基苯基马来酰亚胺的影响。得到的最佳工艺条件是:n(顺丁烯二酸酐)∶n(对硝基苯胺)为1.2∶1,V(甲苯)∶V(DMF)为10∶1;胺化反应温度为20～30℃,环化反应温度为140～150℃,环化反应时间为6h以上;对甲基苯磺酸用量为反应物总质量的1%～2%;硫酸铜用量为反应物总质量的0.1%～0.5%;对苯二酚用量为反应物总质量的0.1%。在此条件下,产物收率达到85%以上,纯度达到98.1%。

4-羟基苯并三氮唑合成新工艺

以低毒性硫酸汞替代剧毒性氧化汞为催化剂,以苯并三氮唑(BTA)、发烟硫酸、浓硫酸和KOH为原料,采用两步法合成了4-羟基苯并三氮唑(4-OH-BTA),即先将BTA溶于浓硫酸中,以液液均相磺化反应合成4-磺酸基苯并三氮唑(4-SO3H-BTA),然后4-SO3H-BTA在强碱性条件下水解反应合成了4-OH-BTA;分别考察了工艺条件对两步合成反应的影响。实验结果表明,磺化反应的最佳工艺条件为:m(浓硫酸)∶m(发烟硫酸)=60∶40、磺化温度130℃、n(硫酸汞)∶n(BTA)=0.010,在此条件下4-SO3H-BTA的收率为84.1%;水解反应的最佳工艺条件为∶n(KOH)∶n(4-SO3H-BTA)=4.0、水解温度235℃,在此条件下4-OH-BTA的收率为61.0%;两步反应的总收率为51.3%,比氧化汞为催化剂的合成工艺提高了20%左右。

2,4,6-三硝基苯磺酸和葡聚糖硫酸钠诱导的大鼠肠炎模型比较

目的:比较2,4,6-三硝基苯磺酸(TNBS)和葡聚糖硫酸钠(DSS)诱导的两种肠炎大鼠模型。方法:SD大鼠随机分为正常对照组、TNBS模型组和DSS模型组,每组10只。TNBS模型组大鼠采用TNBS 50%乙醇溶液以100 mg/kg一次性灌肠法建立肠炎模型,DSS模型组大鼠采用4%DSS水溶液连续7 d自由饮用建立肠炎模型。观察各组大鼠一般情况,检测血清总胆固醇(TC)和三酰甘油(TG)含量、结肠长度及质量、结肠组织中髓过氧化物酶(MPO)活性,肉眼观察结肠大体外观形态,苏木精-伊红染色观察结肠病理学变化。结果:与正常对照组比较,TNBS模型组大鼠体质量明显减轻,结肠长度明显缩短、单位长度质量明显增加,粪便性状评分、血清TG含量、MPO活性、结肠大体外观评分和病理学评分均明显增加(P<0.05或P<0.01);DSS模型组大鼠体质量明显减轻,结肠长度明显缩短,粪便性状和结肠病理学评分均明显增加(P<0.05或P<0.01)。与DSS模型组比较,TNBS模型组大鼠结肠长度明显缩短、单位长度质量明显增加,血清TC、TG含量和结肠大体外观评分、病理学评分明显增加(P<0.05或P<0.01),组织病理学检查可见明显肠道溃疡与粘连。结论:DSS诱导肠炎模型大鼠粪便评分较TNBS诱导模型低,TNBS诱导肠炎模型大鼠在肠道组织损伤方面较DSS诱导模型更严重、恢复更慢。

Recombinant adeno-associated virus carrying thymosin β4 suppresses experimental colitis in mice

AIMTo investigate the protective effect of a recombinant adeno-associated virus carrying thymosin β4 (AAV-Tβ4) on murine colitis via intracolonic administration.METHODSAAV-Tβ4 was prepared and intracolonically used to mediate the secretory expression of Tβ4 in mouse colons. Dextran sulfate sodium (DSS) was applied to induce the murine ulcerative colitis, and 2,4,6-trinitrobenzene sulfonic acid (TNBS) was used to establish a mouse colitis model resembling Crohn’s disease. The disease severity and colon injuries were observed and graded to reveal the effects of AAV-Tβ4 on colitis. The activities of myeloperoxidase (MPO) and superoxide dismutase (SOD) and the content of malondialdehyde (MDA) were determined using biochemical assays. Colonic levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-10 were measured using ELISA, and mucosal epithelial cell apoptosis and proliferation were detected by TUNEL assay and immunochemistry, respectively.RESULTSRecombinant AAVs efficiently delivered LacZ and Tβ4 into the colonic tissues of the mice, and AAV-Tβ4 led to a strong expression of Tβ4 in mouse colons. In both the DSS and TNBS colitis models, AAV-Tβ4-treated mice displayed distinctly attenuated colon injuries and reduced apoptosis rate of colonic mucosal epithelia. AAV-Tβ4 significantly reduced inflammatory cell infiltrations and relieved oxidative stress in the inflamed colons of the mice, as evidenced by decreases in MPO activity and MDA content and increases in SOD activity. AAV-Tβ4 also modulated colonic TNF-α, IL-1β and IL-10 levels and suppressed the compensatory proliferation of colonic epithelial cells in DSS- and TNBS-treated mice.CONCLUSIONTβ4 exerts a protective effect on murine colitis, indicating that AAV-Tβ4 could potentially be developed into a promising agent for the therapy of inflammatory bowel diseases.

HCl溶液中酸性离子液体对Q235钢的缓蚀作用

通过电化学测试研究了N-(4-磺酸基丁基)三乙基铵硫酸氢盐([(CH2)4SO3HTEA][HSO4])酸性离子液体在25℃、0.5mol/L的HCl溶液中对Q235钢的缓蚀性能。结果表明,该离子液体在一定的浓度范围内能够减缓HCl溶液对Q235钢的腐蚀,当离子液体的浓度为14mmol/L时,缓蚀效果最好。X射线光电子能谱(XPS)表征结果表明,在Q235钢表面离子液体能够形成吸附保护膜,覆盖反应活性中心,减缓HCl溶液对Q235钢的腐蚀。

4-氨基苯基-β-羟乙基砜硫酸酯重氮化反应的研究

本文详细研究了4-氨基苯基-β-羟乙基砜硫酸酯的重氮化条件,得出反应的最佳条件为:反应温度10~15℃,对位酯与酸摩尔比1∶1.1,反应液浓度15%,重氮化时间1 h。此条件重氮化可以有效降低原料成本、减少人工劳动同时减少污染,在染料生产上具有重要的指导意义。