合成琥珀

N-succinimidyl 5---3-pyridinecarboxylate, a useful linker for labeling proteins with astatine and iodine radioisotopes, is synthesized in three steps with 5- bromonicotinic acid as a starting material, and is characterized by nuclear magnetic resonance, mass spectrometer and high performance liquid chromatography.

以5-溴烟酸为起始物，通过3步主要反应合成了一种适用于蛋白质放射性砹标记的偶联剂——5--3-吡啶甲酸 N-琥珀酰亚胺酯，并用核磁共振、质谱、高效液相色谱等进行了表征。

On the basis of these observations , suggest how succinyl-CoA regulates the activity of citrate synthase.

在这些观察的基础上，提出琥珀酰辅酶A如何调节柠檬酸合成的活性。

They were named respectively as muramidase-released protein; succinate dehydrogenase/fumarate reductase flavoprotein subunit (SDHFp/FRDFP, extracellular); bacterial trigger factor; elongation factor G (EF-G, extracellular); PTS system sorbose subfamily I (PTS/MAN-ⅡAB, cytoplasmic); pyruvate kinase; phosphofructokinase, PK.

经MALDI-TOF-MS鉴定，这8个蛋白分别为溶菌酶释放蛋白、琥珀脱氢酶／延胡索酸还原酶黄素蛋白亚单位(SDHFp/FRDFp)、触发因子、延长因子G、细菌糖磷酸转移酶系统甘露糖特异ⅡAB亚单位、丙酮酸激酶、6-磷酸果糖激酶(6-PFK)、色氨酸－tRNA合成酶。

AIM: To study the affinity with tumor cells through series of N-octyl-N'-succinyl chitosan synthesized by using different molecular weight of chitosan.

目的：以不同分子质量的壳聚糖为原料合成系列的N－正辛基－N'-琥珀酰基壳聚糖，考察其与肿瘤细胞的亲和性，为其作为抗肿瘤药物的靶向载体提供依据。

The analysis of 1H NMR showed that the succinyl group was successfully conjugated to the amino group of chitosan molecule, and the degree of substitution of Suc-Chi values increased with increasing succinic anhydride/amino mole ratio or reducing the molecular weight of chitosan.

利用壳聚糖和琥珀酰酐反应合成了N-琥珀酰壳聚糖，1H NMR分析表明通过反应可在壳聚糖的侧氨基引入亲水性的羧基，增加琥珀酰酐／氨基的摩尔投料比或者选择分子质量较小的壳聚糖，有利于提高N-琥珀酰壳聚糖的琥珀酰化度。

Therefore, the metabolic pathway from soybean oil to erythromycin was presumed as follows: soybean oil is metabolized into TCA pathway to generate much α ketoglutaric acid and then generate succinyl CoA by strengthening TCA pathway, and the methylmalonyl CoA is formed from succinyl CoA by isomerization. Finally, methylmalonyl CoA can be used as the precursor for the biosynthesis of erythromycin.

推测豆油经过红色糖多孢菌代谢后进入红霉素合成的一条可能途径：豆油经过代谢后进入TCA循环，并强化了TCA循环的通量，产生了大量α酮戊二酸，再生成琥珀酰CoA，琥珀酰CoA在甲基丙二酰CoA异构酶的作用下生成甲基丙二酰CoA作为红霉素合成的前体。

CoA by strengthening TCA pathway, and the methylmalonyl??CoA is formed from succinyl??CoA by isomerization. Finally, methylmalonyl??CoA can be used as the precursor for the biosynthesis of erythromycin.

餐？戊二酸，再生成琥珀酰CoA，琥珀酰CoA在甲基丙二酰CoA异构酶的作用下生成甲基丙二酰CoA作为红霉素合成的前体。

The main study of this dissertation is shown as follows.1.Two new amphiphilic steroid derivatives(N-cholesteryl succinyl glucosamine, CSG and N-deoxycholyl glucosamine,DCG) were designed and synthesized.Their chemical structures have been confirmed by means of Fourier Transform Infrared Spectrometry,Nuclear Magnetic Resonance Spectrometry and Mass Spectrometry.

设计、合成了新型的两亲性甾族衍生物—N-胆固醇琥珀酰基氨基葡萄糖(N-cholesteryl succinyl glucosamine，CSG)和N-脱氧胆酰基氨基葡萄糖(N-deoxycholyl glucosamine，DCG)，并采用傅立叶红外波谱仪(Fourier TransformInfrared Spectrometry，FT-IR)、核磁共振波谱仪(Nuclear Magnetic ResonanceSpectrometry，NMR)和质谱等分析仪器对原料、中间产物和最终产物的化学结构进行表征。

Seven of them have not been reported.Their structures were confirmed by IR,~1HNMR,MS,and element analysis. 4.Meanwhile,the green methylation procedure of imides was developed by using dimethyl carbonate as methylation reagent.A series of imides,for example,phthalimide,3,4-dibromo-maleimide and succincide were used for substrates.The effects of DABCO(1,4-diazabicyclo [2.2.2]octane)and DBU(1,8-diazabicyclo[5.4.0]undec-7-ene)as a catalyst in this kind of reactions were investigated.2-Bromo-3-(1-methylindolyl-3-yl)-1-methyl-1H-pyrrole-2,5-dione was prepared by using dimethyl carbonate,which further expanded the use of dimethyl carbonate,as a green agent in organic synthesis.

在以硫酸二甲酯为甲基化试剂对3，4-二溴马来酰亚胺进行N-甲基化反应合成3，4-二溴-N-甲基马来酰亚胺的同时，以碳酸二甲酯为甲基化试剂，对3，4-二溴马来酰亚胺、邻苯二甲酰亚胺、琥珀酰亚胺等酰亚胺类化合物的N-甲基化反应进行了研究；考察了1，4-二氮杂双环[2.2.2]辛烷，1，8-二氮杂双环[5.4.0]十一碳-7-烯、碳酸钾和四丁基溴化铵等作为催化剂对碳酸二甲酯N-甲基化反应的反应时间和收率等的影响，并应用碳酸二甲酯为甲基化试剂，合成了N-甲基-3-溴-4-(1-甲基-吲哚-3)-马来酰亚胺。

The derivative is prepared by glycin reacts with the mid-product, which is produced in the combination of PASP synthesis, and the corrosion and scale inhibition efficiency are preliminary investigated.

将合成聚天冬氨酸时产生的中间产物聚琥珀酰亚胺和甘氨酸反应，合成聚天冬氨酸的衍生物，并初步探讨了它的缓蚀阻垢性能。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失