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1.
朱仁发  何勇  於奇 《安徽医药》2005,9(2):89-90
目的以十二酸、乙酸钡、甲酸乙酯等为原料合成α-羟基十二酰乙基磺酸钠.方法反应经缩合、加成得目标产物.结果产物经元素分析、IR、1H-NMR、13C-NMR、ESI-MS确证,以十二酸计,三步合成目标产物α-羟基十二酰乙基磺酸钠总产率55.07%.结论工艺流程操作简便,产率较高、产品质量易于控制,适合于大规模制备.  相似文献   

2.
朱仁发  马翔  何勇  於奇 《安徽医药》2005,9(4):249-250
目的探讨以穿心莲内酯为原料合成穿心莲内酯亚硫酸钠的方法.方法反应经加成,得目标产物.结果产物经元素分析、IR、1H-NMR、13C-NMR、EI-Ms确证结构,反应收率为88.5%(以穿心莲内酯计).结论工艺流程简便,产率、纯度较高、产品质量易控,适合于大规模制备.  相似文献   

3.
目的:合成盐酸尼非卡兰中间体1,3-二甲基-6-[2-(对甲苯磺酰氧基)乙基氨基]尿嘧啶.方法:以二甲基脲和氰乙酸为原料经3步反应合成目标产物.结果:以氰乙酸计,总收率44.4%.目标产物的光谱数据与文献报道一致.结论:新的合成方法所用原料价廉易得,适合生产.  相似文献   

4.
2''''-乙酰基-3-酮基-10,11-脱水-6-O-甲氧基红霉素的合成   总被引:1,自引:0,他引:1  
目的:合成泰利霉素中间体2'-乙酰基-3-酮基-10,11-脱水-6-O-甲氧基红霉素.方法:以6-O-甲氧基红霉素为起始原料,经脱水、酸水解、乙酰化和氧化得到目标产物.结果:以6-O-甲氧基红霉素计,总收率79.9%.目标产物的光谱数据与文献报道一致.结论:该方法合成操作简单,反应条件温和.  相似文献   

5.
目的:改进盐酸度洛西汀的合成工艺.方法:以2-乙酰噻吩为原料,经Mannich、还原拆分、游离、醚化、去甲基化5步反应得目标产物盐酸度洛西汀.结果:以12.3%的收率合成了目标产物,较大幅度地降低了生产成本.结论:改进的盐酸度洛西汀合成工艺优化了反应条件,简化了后处理过程,适合于工业化生产.  相似文献   

6.
目的 合成三个甾体螺内酯-3-酮肟化合物.方法 将在合成Drospirenone时得到的2个含螺内酯的中间体与产物的3位酮基进行成肟的修饰.结果 和结论目标产物经IR、1HNMR、MS确定.  相似文献   

7.
2,N-二甲基-N-(3,3-二苯基丙基)-1-氨基-2-丙醇的合成   总被引:2,自引:0,他引:2  
目的研究2,N-二甲基-N-(3,3-二苯基丙基)-1-氨基-2-丙醇(1)的合成方法.方法以肉桂酸、氯化亚砜、甲胺等为原料,经烃化、氯化、酰化和还原反应得到N-甲基-3,3-二苯基丙胺(5);以3-氯异丁烯为原料,经加成、水解、环合反应得到环氧异丁烷(7),化合物5与7经烃化反应得到目标产物.结果与结论设计的合成路线以肉桂酸计,5步反应总收率为62.7%,合成路线简便易行,适于大规模制备.所合成的目标产物经ESI-MS和1H-NMR确证.  相似文献   

8.
目的:对咪达那新的合成工艺进行改进。方法:以二苯乙腈为起始原料,经缩合1、缩合2及水解得到目标产物。结果:经三步合成了目标产物,总收率为68%,目标化合物结构经1HNMR和MS确证。结论:本合成方法原料易得,反应条件温和,适合工业化生产。  相似文献   

9.
以青霉素G钾盐为原料,经酯化、氧化、开环、取代、氯化、闭环反应合成头孢类中间体GCLE,目标产物及各中间体经熔点、IR、~1H-NMR、HPLC等方法进行分析,反应总收率可达30.2%.  相似文献   

10.
目的:合成4-吡啶丁醇。方法:以4-溴吡啶盐酸盐为原料,经缩合、成盐、催化氢化再游离共4步反应得到目标产物。结果与结论:目标产物的化学结构经1HNMR确证,反应条件温和,操作简单,适宜工业化生产,总收率65.1%。  相似文献   

11.
12.
We report herein the condensation of 4,7-dichloroquinoline (1) with tryptamine (2) and D-tryptophan methyl ester (3) . Hydrolysis of the methyl ester adduct (5) yielded the free acid (6) . The compounds were evaluated in vitro for activity against four different species of Leishmania promastigote forms and for cytotoxic activity against Kb and Vero cells. Compound (5) showed good activity against the Leishmania species tested, while all three compounds displayed moderate activity in both Kb and Vero cells.  相似文献   

13.
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.
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.
  相似文献   

14.
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16.
Lung disease and PKCs   总被引:1,自引:0,他引:1  
The lung offers a rich opportunity for development of therapeutic strategies focused on isozymes of protein kinase C (PKCs). PKCs are important in many cellular responses in the lung, and existing therapies for pulmonary disorders are inadequate. The lung poses unique challenges as it interfaces with air and blood, contains a pulmonary and systemic circulation, and consists of many cell types. Key structures are bronchial and pulmonary vessels, branching airways, and distal air sacs defined by alveolar walls containing capillaries and interstitial space. The cellular composition of each vessel, airway, and alveolar wall is heterogeneous. Injurious environmental stimuli signal through PKCs and cause a variety of disorders. Edema formation and pulmonary hypertension (PHTN) result from derangements in endothelial, smooth muscle (SM), and/or adventitial fibroblast cell phenotype. Asthma, chronic obstructive pulmonary disease (COPD), and lung cancer are characterized by distinctive pathological changes in airway epithelial, SM, and mucous-generating cells. Acute and chronic pneumonitis and fibrosis occur in the alveolar space and interstitium with type 2 pneumocytes and interstitial fibroblasts/myofibroblasts playing a prominent role. At each site, inflammatory, immune, and vascular progenitor cells contribute to the injury and repair process. Many strategies have been used to investigate PKCs in lung injury. Isolated organ preparations and whole animal studies are powerful approaches especially when genetically engineered mice are used. More analysis of PKC isozymes in normal and diseased human lung tissue and cells is needed to complement this work. Since opposing or counter-regulatory effects of selected PKCs in the same cell or tissue have been found, it may be desirable to target more than one PKC isozyme and potentially in different directions. Because multiple signaling pathways contribute to the key cellular responses important in lung biology, therapeutic strategies targeting PKCs may be more effective if combined with inhibitors of other pathways for additive or synergistic effect. Mechanisms that regulate PKC activity, including phosphorylation and interaction with isozyme-specific binding proteins, are also potential therapeutic targets. Key isotypes of PKC involved in lung pathophysiology are summarized and current and evolving therapeutic approaches to target them are identified.  相似文献   

17.
18.
This study explored gender-related symptoms and correlates of alcohol dependence in a crosssectional study of 150 men and 150 women with a lifetime diagnosis of alcohol use disorders (AUD). Participants were recruited in equal numbers from treatment settings, correctional centres and the general community. Standardized measures were used to determine participants' use of substances, history of psychiatric disorders and psychosocial stress, their sensation seeking and family history of substance use and mental health disorders. Multivariate analyses were used to detect patterns of variables associated with gender and the lifetime severity of AUD. Men had a longer history of severe AUD than women. Women had similar levels of alcohol dependence and medical and psychological sequelae as men, despite 6 fewer years of AUD. More women than men had a history of severe psychosocial stress, severe dependence on other substances and antecedent mental health problems, especially mood and anxiety disorders. There were differences in family history of alcohol-related problems approximating same-gender aggregation. The severity of a lifetime AUD was predicted by its earlier age at onset and the occurrence of other disorders, especially anxiety, among both men and women. The limitations in the generalizability of these findings due to sample idiosyncrasies are discussed.  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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