β-苯乙基异氰酸酯的简便合成法

目的：研究β－苯乙基异氰酸酯的合成。方法：以β－苯乙胺为原料，通过与三光气反应，一步制得β－苯乙基异氰酸酯。结果：所得产物经ＩＲ、ＭＳ确证，折光率与文献一致，收纺７８．９％。结论：该方法操作简便，反应条件温和，收纺较高，适宜工业规模制备。     

萘呋胺酯的新法合成

以糠醛和丙二酸二乙酯为原料，经Ｋｎｏｅｖｅｎａｇｅｌ缩合ＲａｎｅｙＮｉ催化加氢，酯交换，烷基化和水解脱羧合成了萘呋胺酯。     

米氟米特中间体5—甲基—4—异恶唑甲酸的合成

以乙酰乙酸乙酯为起始原料，经缩合得到乙氧亚甲基乙酰乙酸乙酯，然后与盐酸羟胺环合形成5－甲基－4－异恶唑甲酸乙醋，再经水解得5－甲基－异恶唑甲酸，后两步收率可达50％以上，总收经41％，产品纯度提高到99％。     

烯二炔类抗肿瘤抗生素全合成研究：Ⅲ.十元环烯二炔单元开链 …

以环戊酮为原料 ,经七步反应 ,得到十元环状烯二炔单元开链衍生物 ,为进一步合成十元环状烯二炔类化合物打下基础。本文中共合成了 6个新化合物 ,其结构均经 1 H- NMR谱和质谱确证。     

烯二炔类抗肿瘤抗生素全合成研究Ⅲ.十元环状烯二炔单元开链衍生物的合成

以环戊酮为原料,经七步反应,得到十元环状烯二炔单元开链衍生物,为进一步合成十元环状烯二炔类化合物打下基础.本文中共合成了6个新化合物,其结构均经1H-NMR谱和质谱确证.     

烯二炔类抗肿瘤抗生素全合成研究Ⅴ.通过分子内的偶联反应合成十元环状烯二炔

以顺式1，2-二氯乙烯为原料，经六步反应，得到与芳环骈连的共轭环状烯二炔，本文首次以分子内的偶联反应作为环合反应来合成环状烯二炔。     

西多夫韦的合成工艺改进

目的改进核苷类抗病毒药物西多夫韦的合成工艺。方法以（S）-2，3-缩异丙叉甘油醛为起始原料．经还原、酰化、缩合、水解、醚化、酯交换、脱三苯甲基保护、水解、脱苯甲酰基保护、酸化等反应制得抗病毒药物西多夫韦。结果与结论目标化合物结构经。H-NMR、质谱,^13C-NMR、红外光谱确证。总收率为7．36％。比文献收率提高了1．56％。改进后的方法反应条件温和、操作简便，有利于工业化生产。     

烯二炔类抗肿瘤抗生素全合成研究.含芳环烯二炔单元开链衍生物的合成

以 2 -溴苯甲醛为原料 ,经 6步反应 ,得到含芳环十元环状烯二炔单元开链衍生物。共合成 12个新化合物 ,其结构均经1 NHMR谱和质谱确证     

烯二炔类抗肿瘤抗生素全合成研究Ⅳ. 含芳环烯二炔单元开链衍生物的合成

以2-溴苯甲醛为原料,经6步反应,得到含芳环十元环状烯二炔单元开链衍生物。共合成12个新化合物,其结构均经1NHMR谱和质谱确证。     

反相高效液相色谱法分离纯化三七超临界二氧化碳萃取物中人参炔醇

目的研究人参炔醇单体的制备技术。方法以超临界二氧化碳萃取设备萃取三七,获得的超临界萃取物经硅胶吸附可除去大部分极性较大的杂质,经反相高效液相色谱法分离制备人参炔醇单体。结果经UV、IR、MS、NMR鉴定,确定为人参炔醇,纯度达到98％。结论该方法简单,重复性较好,采用的溶剂系统经济环保、沸点低、易于回收。     

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.

---

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.     

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.     

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.