Vilsmeir法合成头孢曲松钠的工艺研究

目的 探讨头孢曲松钠的Vilsmeir法合成工艺。方法 用二氯硫酰代替二氯亚硫酰来制备得到改进的Vilsmeir试剂，用vilsmeir试剂活化的氨噻肟乙酸同7-ACT缩合反应制备头孢曲松钠。结果 与讨论Vilsmeir法合成工艺简单、便宜、收率达85％。     

Vilsmeir法合成头孢曲松钠的工艺研究

目的探讨头孢曲松钠的Vilsmeir法合成工艺.方法用二氯硫酰代替二氯亚硫酰来制备得到改进的Vilsmeir试剂,用vilsmeir试剂活化的氨噻肟乙酸同7-ACT缩合反应制备头孢曲松钠.结果与讨论Vilsmeir法合成工艺简单、便宜、收率达85%.     

硫普罗宁的合成

硫普罗宁(tiopronin,1)是一种含巯基药物,化学名为 N-(2-巯基丙酰)甘氨酸。它用作化疗及放疗保护剂、保肝剂及重金属解毒剂。毒性低,副作用小。硫普罗宁的合成可根据引入巯基的试剂和先后不同有多种方法。我们用硫代苯甲     

头孢曲松钠结晶工艺研究进展

头孢曲松钠属于第三代半合成头孢菌素类抗生素，在抗菌药物中占有非常重要的地位。本文着重介绍头孢曲松钠的发展现状、制备工艺及各种操作条件对产品质量的影响情况，并对今后的发展前景作了展望。     

氯吡格雷中间体α-氯(2-氯)苯乙酸甲酯合成工艺的优化

目的:探讨合成α-氯(2-氯)苯乙酸甲酯的工艺优化。方法:以邻氯扁桃酸甲酯为原料、二氯亚砜为氯化试剂合成α-氯(2-氯)苯乙酸甲酯;设计正交试验,以邻氯扁桃酸甲酯与二氯亚砜投料比、反应温度、反应时间为因素,以产率为指标优化合成工艺条件,并进行验证试验。结果:确定了最佳反应条件即邻氯扁桃酸甲酯与二氯亚砜投料比为2∶3,反应时间为1h,反应温度40℃;以此条件合成产品收率≥92%,纯度≥99%。结论:所得合成工艺条件适用于合成α-氯(2-氯)苯乙酸甲酯。     

硫普罗宁的合成工艺改进及质量控制研究

目的改进硫普罗宁的合成工艺和含量测定方法。方法以α-溴丙酸为原料,经过酰氯化后,再与甘氨酸反应得到α-溴丙酰甘氨酸,然后与新制的二硫化钠反应,制得α-巯丙酰甘氨酸的二聚体,产物不经分离直接于锌粉反应制得硫普罗宁;采用化学滴定法进行含量测定。结果总收率为29％,含量合格。结论硫普罗宁的合成工艺及含量测定改进后的方法更适合工业生产。     

纳米硫凝胶的制备及质量控制

目的制备纳米硫凝胶,并建立其质量控制标准。方法液相法合成纳米硫,以卡波姆940为主要基质制备纳米硫凝胶,采用pH检测、含量测定、稳定性考察等方法控制凝胶质量,并进行皮肤刺激性试验。结果合成的纳米硫粒径为50～80 nm。纳米硫凝胶在室温下均匀细腻,流动性较好,pH为6.5,其含量和稳定性等均符合质量控制标准。结论纳米硫凝胶制备工艺可行,性质稳定,质量可控。     

头孢曲松钠中残留的三嗪环的定性与定量分析

目的控制头孢曲松钠中三嗪环的残留量,减少过敏反应的发生,促进工艺改进。方法作者采用MS、IR与NMR等波谱技术对制备的三嗪环(triazin)样品进行结构确认,用HPLC法对其进行纯度测定;根据欧洲药典方法,用质量分数为1.0%的头孢曲松钠对照液做对照,以头孢曲松钠供试液中三嗪环的峰面积与质量分数为1.0%的对照液中头孢曲松钠的峰面积比来计算三嗪环的含量。结果制备三嗪环样品的工艺能够获得目标产物,质量分数纯度为99.72%;三嗪环与头孢曲松的相对保留时间为0.59,其含量质量分数为0.099%。结论该方法适合头孢曲松钠中残留的三嗪环的定性定量分析,其含量在安全限度范围内(质量分数不超过1.0%),患者可以放心使用。     

注射用琥珀酰明胶的制备

目的制备注射用琥珀酰明胶,以提高其稳定性及运输贮藏的便易性。方法合成琥珀酰明胶,并用IR、1H-NMR及UV光谱方法对其进行表征,采用喷雾干燥和冷冻干燥工艺制备注射用琥珀酰明胶,同时对所制备产品的再分散性质进行了初步考察。结果合成条件为:明胶质量浓度为200 mg.L-1,琥珀酸酐质量浓度为10 mg.L-1,pH值为10,温度90℃,时间2 h。冷冻干燥法制备的注射用琥珀酰明胶与琥珀酰明胶对照品的1H-NMR、IR及UV谱图均相符。以质量浓度50 mg.L-1的甘露醇为冻干保护剂制备的产品外观蓬松饱满,复溶时间短。配成输液后渗透压为288 mmol.L-1,pH值为7.19。结论运用丁二酰化法合成琥珀酰明胶,以质量浓度50 mg.L-1甘露醇为冻干保护剂,利用冷冻干燥法可相对较稳定地制备拥有较好外观及溶解度的注射用琥珀酰明胶,且配制成输液后渗透压及pH值符合静脉用药要求。     

盐酸奥兰西丁的合成工艺改进

以氰亚胺二硫代碳酸二甲酯为原料与氨水及正辛胺经"一勺烩"法得到中间体N1-正辛基-N3-氰胍(2);3,4-二氯氯苄与乌洛托品反应,再经酸水解得到3,4-二氯苄胺盐酸盐(5).中间体2和5通过加成反应得到盐酸奥兰西丁,结构经IR、MS、1H-NMR以及元素分析确证.该合成方法工艺简单,总收率由36.6%提高到56.2%,易于工业化生产.     

Efficacy of gut lavage,hemodialysis, and hemoperfusion in the therapy of paraquat or diquat intoxication

Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.

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Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.

     

In vitro studies on sterically stabilized liposomes (SL) as enzyme carriers in organophosphorus (OP) antagonism

This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine.     

Aquatic Insects and Trace Metals: Bioavailability,Bioaccumulation, and Toxicity

Abstract

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.     

Alzheimer’s disease – current trends in basic and clinical research. Highlights from the 16th ECNP

Advances in the molecular biological knowledge of neuronal nicotinic acetylcholine receptors (nAChRs) have led to a growing interest by the pharmaceutical industry in the development of novel compounds that selectively modulate nAChR function. The ability of (-)-nicotine, an activator of nAChRs, to enhance attentional aspects of cognition in animals and humans, to exert neuroprotective and anxiolytic-like effects, and presumably to mediate the negative correlation between smoking and Alzheimer's (and Parkinson's) Disease, has focused interest on the potential therapeutic utility of modulators of nAChR function for treatment of some of the deficits associated with these progressive, neurodegenerative conditions. Numerous compounds are known which activate nAChRs and which might serve as lead compounds toward the development of such agents. The pharmacologic diversity of neuronal nAChR subtypes suggests the possibility of developing selective compounds which would have more favourable side-effect profiles than existing agents. This broader class of agents, collectively called cholinergic channel modulators (ChCMs), is anticipated to encompass compounds which would have more favourable side-effect profiles than existing agents, which generally exhibit low selectivity. This selectivity may be achieved by preferentially activating some subtypes of nAChRs (i.e., Cholinergic Channel Activators, ChCAs) or inhibiting the function of other subtypes (Cholinergic Channel Inhibitors, ChCIs). An overview of the biology of nAChRs and the rationale for the use of ChCMs for the treatment of dementia related to neurodegenerative diseases are presented, followed by a discussion of lead compounds and compounds under consideration for clinical evaluation.     

Steroidal sapogenin contents in some domestic plants

In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins.