共查询到20条相似文献,搜索用时 78 毫秒
1.
具有生物活性的三烃基锡化合物的研究进展 总被引:2,自引:0,他引:2
主要对具有生物活性的三烃基锡化合物的研究进行回顾,其中包括不具有含硅基团的单一三烃基锡化合物、混合三烃基锡化合物,具有含硅基团的单一三烃基锡化合物、混合三烃基锡化合物,以及其它结构类型的三烃基锡化合物的生物活性研究。 相似文献
2.
3.
4.
5.
氮杂环化合物是一类具有重要应用价值和良好生物活性的化合物,在生物、医药、农药等领域的应用非常广泛,一直是人们研究的热点,四氮唑类杂环化合物又是其中的一类重要五元芳杂环化合物。因其在医药上取得广泛的应用引起人们越来越多的关注。文章对杂环化合物、氮杂环化合物的发展进行了简单的叙述,并对不同种类四氮唑芳杂环化合物的发展及其应用做了详细阐述。 相似文献
6.
7.
8.
<正>通过合成廉价的新型化合物以寻找新的杀蚊剂,驱避剂和杀菌剂。同时,通过构效分析也可能发现另外的活性化合物。广谱活性的化合物可以成为理想的农药商品。其方法系评估一系列具有相同基础结构、不同取代基的化合物。在此项研究中,Maia Tsikolia等聚焦含氟化合物,此是由于在过去10年含氟化合物已成为控制农业害虫越来越重要的一类化合物。许多含氟的化合物成为有效的杀虫和杀菌剂。如含有三氟甲基的氟虫腈、氟啶虫酰胺和 相似文献
9.
天然产物泛指来源于植物、动物、微生物、海洋生物和矿物的化合物。天然产物的来源有多种途径,从天然产物中寻找有活性的化合物作为先导化合物创制新药是世界药学工作者公认的有效途径之一。天然来源药物可分为原始天然化合物、经半合成或全合成得到的化合物。 相似文献
10.
本文通过作者编制的计算机程序,计算了碳硝基化合物、硝胺化合物、硝酸酯化合物等近百个硝基化合物的键极性诱导指数,讨论了键极性诱导指数与化合物安定性的关系。 相似文献
11.
Red-backed salamanders, Plethodon cinereus, show a variety of alarm responses to chemical cues from eastern garter snakes, Thamnophis sirtalis. We measured the foraging activity of red-backed salamanders exposed to water soiled by a garter snake (fed P. cinereus) or to unsoiled water. Salamanders exposed to snake-soiled water showed less foraging activity than salamanders exposed to unsoiled water; therefore, predators could have nonlethal effects on salamander populations. Our results also show additional factors influenced salamander foraging activity. Salamander foraging activity and responsiveness to chemical cues do not appear to have been affected by sex or food deprivation. Salamander foraging activity does appear to have been influenced by activity biorhythms. Foraging activity of animals in both treatments showed a bimodal periodicity that is consistent with natural activity patterns controlled by internal biorhythms. Exposure to snake-soiled water significantly reduced foraging activity during periods of peak foraging activity, but had a subtler effect0 on foraging activity during natural lulls in activity. We suggest that both activity biorhythms and exposure to chemical cues are important factors affecting salamander foraging behavior. 相似文献
12.
酰氨基硫脲类化合物是一类重要的有机硫化合物,它们不仅是合成多种杂环化合物的有机中间体,而且具有杀菌、杀虫、抗结核、抗癌、徐草及调节植物生长等多种重要的生物活性.介绍了酰氨基硫脲及其杂环衍生物的应用进展及合成方法,同时对该类化合物的广阔开发前景进行了展望. 相似文献
13.
14.
A. G. Gopala Krishna J. V. Prabhakar 《Journal of the American Oil Chemists' Society》1992,69(2):178-183
The role of water activity on the formation of peroxides and carbonyl compounds during lipid oxidation is important to know
because there could be either beneficial or detrimental effects of water activity on lipid oxidation in stored foods. Therefore,
methyl linoleate was chosen as a model lipid and was autoxidized to 1% at water activity ranging from 0.02 to 0.79 at 37°C.
Oxygen uptake was monitored manometrically. The peroxide and carbonyl contents were determined upon termination of the autoxidation
studies. Methyl linoleate autoxidation was characterized by three phases: i) an initial induction period of no oxygen absorption;
ii) a slow rate of oxygen absorption, up to 0.15% oxidation; and iii) a relatively faster rate of oxygen absorption beyond
0.15% up to 1% oxidation. Water activity had considerable influence during the first phase. There was no induction period
at or below water activity 0.22. The induction period begins at water activity 0.32 and could be extended to a limit with
increase in water activity. Once the induction period was passed water activity had no influence on the rate of oxidation.
However, during the second and third phases water activity becomes important in the stabilization of peroxides/hydroperoxides
and decides the course of secondary reactions that follow peroxide decomposition. Higher water activity values, particularly
water activity 0.67, tended to stabilize peroxides. Water activity had considerable influence on the formation of secondary
products of autoxidation as evidenced by the variation in the type and quantity of carbonyl compounds at different water activity
values. 相似文献
15.
16.
17.
基于催化剂全混流流动状态和呈指数形式的催化剂年龄概率密度函数,经催化剂失活动力学方程推导,确定了关联催化剂碳含量、金属沉积量、催化剂置换率、再生器温度和水蒸气分压的平衡催化剂活性或微反活性模型方程。对工业催化裂化装置操作数据进行模拟计算,确定了催化剂失活模型参数,建立了具有较高模拟计算精度的裂化催化剂失活动力学和平衡催化剂活性模型。比较模型参数大小可知,V沉积对催化剂活性的影响最大,其次是Ni和Fe,Na的影响最小。模型预测结果表明,随着平衡催化剂金属沉积量或碳含量减少,催化剂单耗增大,平衡催化剂活性或微反活性逐渐增大。适当降低再生器温度和催化剂藏量有利于提高平衡催化剂活性。 相似文献
18.
Crude extracts of the root of the resistant legume,Lupinus angustifolius, showed feeding deterrent activity toCostelytra zealandica andHeteronychus arator larvae. Nine 5-hydroxyisoflavones were isolated from an active fraction and their feeding deterrent activity and antifungal activity was measured. High feeding-deterrent activity was associated with high antifungal activity with some exceptions. 相似文献
19.
乙炔加氢催化剂活性对反应器入口CO浓度变化非常敏感,量化CO浓度对催化剂活性的影响程度并预测催化剂活性与反应器入口温度的对应关系十分必要。通过反余切三角函数建立催化剂活性随CO浓度变化的模型,定量描述CO浓度对催化剂活性的影响,并结合反应器入口温度、入口原料气总质量、入口与出口各物质的含量等实际生产数据,优化动力学参数和失活模型参数,定性和定量描述催化剂活性变化后反应器入口温度的调整方法,利用此模型结合相关数据考察反应器入口温度对催化剂活性的影响。 相似文献
20.
目的分离纯化牛蛙皮肤抗菌肽,并检测其活性。方法通过刺激与浸提的方法,得到牛蛙皮肤抗菌肽粗提物,测定其抑菌活性及最低抑菌浓度。利用SephadexG-50凝胶过滤和反相高效液相色谱(RP-HPLC)分离纯化粗提物,用质谱仪测定多肽的相对分子质量及氨基酸序列,并进行活性检测。结果两种方法提取的牛蛙皮肤抗菌肽粗提物均具有较强的抑菌活性,纯化后的多肽相对分子质量约为4370,N-端含22个氨基酸,与其他两栖类来源的抗菌肽同源性较低。活性试验表明均无胰蛋白酶水解活性,存在一定的胰蛋白酶抑制剂活性,有轻微的溶血活性,不具有局部出血活性,具有抗凝和溶栓作用。结论已成功分离并纯化了1种新的牛蛙皮肤抗菌肽。 相似文献