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1.
4—氨基—1—甲基—3—丙基吡唑—5—甲酰胺的合成   总被引:1,自引:0,他引:1  
以2-戊酮和草酸二乙酯为起始原料,经缩合,环合、甲基化、水解、硝化、氨解、还原等7步反应合成了新型磷酸二酯酶5型(PDE5)抑制剂西地那非的关键中间体-4-氨基-1-3-丙基吡唑-5-甲酰胺。  相似文献   

2.
2—羟基—3—氨基—4—苯丁酸的合成   总被引:3,自引:1,他引:3  
2-羟基 - 3-氨基 - 4-苯丁酸 (1 )是制备二肽免疫增强剂类抗癌新药乌苯美司的关键中间体 ,有多种合成方法 ,如 α-氨基苯乙酮法 [1]、α-氨基苯丙醛法 [2 ]、α-氨基苯丁腈法[3] 、苯丁烯酸甲酯法 [4 ] 、苯丙氨酸法 [5]和苹果酸二乙酯法 [6]等。以上各法均存在不同缺点 ,如α-氨基苯乙酮法 ,总收率不到 1 0 % ;α-氨基苯丙醛法和α-氨基苯丁腈法 ,均用剧毒氰化钾(钠 ) ;苯丁烯酸甲酯法用爆炸性的过氧化物 ;苯丙氨酸法合成步骤长 ,且用氢化铝锂和氰化钠等试剂 ;苹果酸二乙酯法中的烃化反应需在 - 78℃的低温下进行。上述各法均不适合工业化…  相似文献   

3.
通过本实验验证了从万年蒿中提取的新化合物的化学结构,并且摸索出一条合成2-羟基-6-甲氧基丙乙酮-4-O-β-D-葡萄糖甙的途径。  相似文献   

4.
5.
报道了7-氯-6-氟-4-乙氧基喹啉-3-羧酸乙酯(1)在 DMF 和 DMSO 中的转化反应。在DMSO中加热或用碘化四丁铵催化,转化率100%,转化产物经证明为2和8的混合物。并用~1HNMR 测定了转化产物中2的相对含量。同时考察了3乙基化时不同溶剂对1和2生成比例的影响。  相似文献   

6.
7-氨基-3-甲氧甲基-3-头孢烯-4-羧酸(1)是合成第三代口服头孢菌素头孢泊肟酯(cefpodoxime proxetil)的关键母体。合成  相似文献   

7.
报道了以2,6-二羟基-3-甲基-4-甲氧基苯甲酸酯为原料,用Vilsmeier甲酰化反应制备标题化合物的新方法。  相似文献   

8.
9.
以对乙酰胺基苯酚为原料,通过醚化、环合、水解、重氮化和氟化合成6-氟-2,3-二氢苯并吡喃-4-酮(2)。曾试图以Michael反应合成化合物4,但丙烯腈被引入对乙酰胺基苯酚的氮原子,得到化合物8。化合物5~9均未见文献报道。  相似文献   

10.
铁螯合剂1-羟乙基-2-乙基-3-羟基吡啶-4-酮的合成SYNTHESISOF1┐HYDROXYETHYL┐2┐ETHYL┐3┐HYDROXYPYRID┐4┐ONESASIRONCHELATORS吉爱国(山东医科大学药学系,济南250012)JIAi...  相似文献   

11.
L—焦谷氨酸对抗从氨酸钠诱发的大鼠皮层神经元损伤   总被引:2,自引:0,他引:2  
目的:在大鼠皮层神经元研究L-吡咯烷酮羧酸(L-PGA)对谷氨酸钠(Glu)诱发神经毒性的拮抗作用。方法:原代培养的皮层神经元取自16d龄的胎鼠,与Glu作用30分钟,24后测定神经元的存活及增益昌质中亚硝酸盐的浓度;以Fura 2-AMo xleqmw 〖Ca^2+〗;荧光探针,,AR-CM-MIC阳离子测定系统测定〖Ca^2+〗i。结果:L-PGA10-80βmol.L^-1浓度依赖地抑制G  相似文献   

12.
目的:研究皮质酮(Cor)对原代培养海马神经细胞存活和海马神经细胞电压依赖性钙通道(VDCC)的影响。方法:原代海马神经细胞存活率测定用MTT比色法。海马神经细胞上VDCC内向Ca~(2 )电流检测采用全细胞膜片箝技术。结果:Cor可浓度依赖地损伤原代海马神经细胞和皮层神经细胞,IC_(50)分别为3.2μmol·L~(-1)和85μmol·L~(-1),Cor(1μmol·L~(-1)-0.1mmol·L~(-1))喷射于海马神经细胞表面即刻显著促进电压依赖性Ca~(2 )内流,其最大升幅分别是53%,191%和84%,而且Cor诱导的钙内流增加是非浓度依赖和非电压依赖的。结论:Cor可显著促进海马神经细胞电压依赖性钙通道开放,该作用可能是Cor海马神经毒性作用的机制之一。  相似文献   

13.
The neurotoxicity of interleukin-6 (IL-6) and sodium nitroprusside (SNP, CAS 13755-38-9) was examined using primary cultures of rat hippocampal neurons. The cell viability was significantly reduced after the cultures were co-incubated with IL-6 4, 40, 400 ng/ml or SNP 1, 10, 100 mumol/l for 24 h. In addition, N omega-nitro-L-arginine (NNA, CAS 2149-70-4) at 0.1 mmol/l, when co-added with IL-6 400 ng/ml in cultures, significantly increased IL-6 reduced viability from 78.3 +/- 6.7% to 113.3 +/- 10.0%. These results indicate that IL-6 exerts neurotoxicity on cultured hippocampal neurons probably via overformation of nitric oxide in cultures.  相似文献   

14.
褪黑激素对大脑皮层谷氨酸释放及其神经毒的拮抗作用   总被引:7,自引:0,他引:7  
AIM: To observe the effects of melatonin (Mel) on glutamate (Glu) release from the cortical synaptosomes in old mice and on neurotoxicity induced by KCl, Glu in cultured cortical cells of fetal rat and to explore the antiaging mechanism of Mel. METHODS: Glu release by the synaptosomes in old mouse cerebral cortex was detected in a spectrofluorophotometer. The neuronal viability in primary cultures from rat cerebral cortex was assessed using MTT stain and lactate dehydrogenase (LDH) efflux in the bathing medium. RESULTS: Mel inhibited the K+ (30 mmol.L-1)-induced Glu release from synaptosomes either in calcium dependent or independent conditions [control (10.6 +/- 1.1), (9.2 +/- 0.7) mumol.g-1 (protein); Mel 0.1 mumol.L-1 (6.5 +/- 0.9), (7.5 +/- 0.6) mumol.g-1 (protein), respectively, P < 0.01 vs control group), increased MTT activity (control 0.67 +/- 0.04, 0.81 +/- 0.03; Mel 0.1 mumol.L-1 0.715 +/- 0.023, 0.925 +/- 0.027, P < 0.01 vs control group] and decreased LDH efflux (control 0.400 +/- 0.016, 0.379 +/- 0.016; Mel 0.1 mumol.L-1 0.345 +/- 0.021, 0.340 +/- 0.012, respectively, P < 0.01 vs control group), therefore, protected the neuronal viability against KCl and Glu-induced injury. CONCLUSION: The inhibitory effect of Mel on Glu release from cortical synaptosome and the protective effect of Mel on cortical neurons against neurotoxicity are its antiaging mechanisms.  相似文献   

15.
冯征  张均田 《药学学报》2000,35(12):881-885
目的 观察一氧化氮(NO)在谷氨酸(Glu),β-淀粉样蛋白[β-AP(1-40)]引起神经细胞损伤中的作用以及丹酚酸B(Sal B)对β-AP(1-40)引起的神经细胞损伤保护作用。方法 原代培养大鼠皮层神经元,建立了硝普钠(SNP),Glu,β-AP(1-40)等3种损伤模型,用形态学观察、MTT比色法、Griess法分别测定神经元活力,培养液中乳酸脱氢酶(LDH)漏出和NO释放。结果 Glu和β-AP(1-40)可以引起神经元NO的释放增加,造成神经毒性。nNOS在Glu的毒性中起重要作用,iNOS可能在Aβ1-40的毒性中起作用。Sal B能显著增加细胞活力,降低LDH释放率,并剂量依赖地减少NO释放。 结论 NO介导了Glu和β-AP(1-40)的毒性,Sal B可以通过减少NO释放,改善β-AP(1-40)的毒性作用。  相似文献   

16.
仲崇波  张炜  王晓良 《药学学报》2002,37(6):415-418
目的探讨donepezil对大鼠海马和新皮层锥体神经元具有延迟整流样特性钾电流(IK)的影响。方法 用膜片钳全细胞记录法。结果Donepezil在微摩尔水平即可抑制IK,并呈剂量依赖性和电压依赖性,且可使IK的稳态激活曲线向超级化的方向移动。结论低浓度donepezil即可抑制大鼠海马和新皮层锥体神经元电压激活的IK,此作用可能与其抑制胆碱酯酶活性协同,参与药物的治疗效应。  相似文献   

17.
L Zhu  J Wu  H Liao  J Gao  X N Zhao  Z X Zhang 《中国药理学报》1997,18(4):344-347
AIM: To determine whether the extract of leaves of Ginkgo biloba L (EGb) and several active constituents of EGb have protective effects against glutamate (Glu)-induced neuronal damage. METHODS: Microscopy and image analysis of nucleus areas in the arcuate nuclei (AN) of mice were made. The neuronal viability in primary cultures from mouse cerebral cortex was assessed using MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide] staining and the intracellular free calcium concentration ([Ca2+]i) of single neuron was measured using Fura-2. RESULTS: EGb (2.5 mg.L-1) and its constituent ginkgolide B (Gin B, 2 mg.L-1) protected the neuronal viability against Glu-induced injury, and prevented the Glu-induced elevation in [Ca2+]i. EGb (3-10 mg.kg-1) attenuated the decrease of nucleus areas in arcuate nuclei induced by Glu (1 g.kg-1, s.c.). CONCLUSION: EGb and Gin B prevent neurons from Glu neurotoxicity through reduction of the rise in [Ca2+]i.  相似文献   

18.
盛瑞  刘国卿 《药学学报》2003,38(5):337-341
目的考察9-(4-乙氧羰基苯氧基)-6,7-二甲氧基-1,2,3,4-四氢吖啶盐酸盐(EDT)对自由基致原代培养大鼠皮层神经毒及小鼠脑缺血损伤的影响。方法原代培养的鼠皮层神经细胞,用H2O2致自由基损伤模型,测定细胞内丙二醛(MDA)及超氧化物歧化酶(SOD)活性。结扎单侧颈总动脉及迷走神经造成小鼠慢性脑缺血模型,用跳台法研究EDT对记忆障碍的影响。同时,检测了大脑皮层形态学变化,脑匀浆内MDA,NO含量及SOD活力。结果在原代培养神经元,0.01~3 μmol·L-1 EDT浓度依赖地抑制H2O2诱发的MDA生成及SOD活力降低。在小鼠脑缺血模型,EDT 2.5,5和10 mg·kg-1 ig 5 d可显著改善脑缺血小鼠的记忆障碍,对抗脑内NO释放及MDA生成,增加SOD活力。结论EDT能有效对抗自由基诱发的神经元毒性及脑缺血损伤。  相似文献   

19.
目的研究阿魏酸钠对β蛋白片段1-42所致培养海马神经元损伤的保护作用及机制。方法原代培养海马神经元,阿魏酸钠(50、100、200μmol·L-1)预处理6 h后,加入50 nmol·L-1的Aβ1-42作用72 h,MTT法测海马神经元细胞存活率,应用倒置相差显微镜和微管相关蛋白-2(MAP-2)免疫荧光染色观察神经元树突的生长,Western蛋白印迹法检测海马神经元磷酸化mTOR和p70s6K蛋白表达。结果与对照组相比,Aβ1-42引起海马神经元细胞的存活率明显降低(P<0.01),可使培养海马神经元出现明显退行性改变,表现为树突串珠样改变和突起回缩,树突总长度和末梢分支数明显减少,磷酸化的mTOR和p70s6K蛋白表达水平明显降低(P<0.01)。应用阿魏酸钠(50、100、200μmol·L-1)预处理6 h可明显对抗Aβ1-42引起的神经元损伤及蛋白表达的改变(P<0.01)。结论阿魏酸钠通过上调磷酸化的mTOR/p70s6K对抗Aβ1-42引起的海马神经元损伤。  相似文献   

20.
葛根素抗谷氨酸对小鼠神经细胞兴奋毒的作用   总被引:34,自引:0,他引:34  
AIM: To study the effects of puerarin (Pue) against injury of cultured neurons by sodium glutamate (Glu). METHODS: Neuronal damage induced by Glu, N-methyl-D-asparate (NMDA), and kainic acid (KA), as well as the actions of Pue and some excitatory amino acid antagonists (EAAA), were measured by determining the leakage of lactate dehydrogenase (LDH) from nerve cells. RESULTS: The 24-h leakage of LDH was increased from cells exposed either to Glu 100 and 500 mumol.L-1 for 15 min (from 20 +/- 4 kU/g protein in control group to 35 +/- 3 kU/g protein in Glu 100 mumol.L-1 group and to 46 +/- 6 kU/g protein in Glu 500 mumol.L-1 group) or to NMDA 500 mumol.L-1 or KA 500 mumol.L-1 for 45 min (from 19 +/- 4 kU/g protein in control group to 27 +/- 3 kU/g protein in NMDA group and to 30 +/- 5 kU/g protein in KA group). Pre and post-treatment with Pue (100 mumol.L-1) decreased the leakage of LDH, which was similar to the effects of EAAA kynurenic acid (from 35 +/- 3 kU/g protein in Glu 100 mumol.L-1 to 20 +/- 5 kU/g protein in kynurenic acid group and to 22 +/- 3 kU/g protein in Pue group), DL-2-amino-5-phosphonovaleric acid (APV) (from 27 +/- 3 kU/g protein in NMDA damaged group to 183 kU/g protein in APV group and to 19 +/- 5 kU/g protein in Pue group) or 6,7-dinitroquinoxaline-2,3(1H,4H)-diane (DNQX) (from 30 +/- 5 kU/g protein in KA damaged control to 22 +/- 5 kU/g protein in DNQX group and to 20 +/- 4 kU/g protein in Pue group). Post-treatment with Pue (100 mumol.L-1) was able to reduce 24-h leakage of LDH from neurons expos ed to Glu 100 mumol.L-1 for 15 min (from 35 +/- 3 kU/g protein to 27 +/- 4 kU/g protein). CONCLUSION: Pue had protective effects on neurons damaged by Glu, NMDA, or KA.  相似文献   

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