新型1,2,4-三唑重金属离子荧光淬灭剂的合成、表征与性能

为寻找快速显示重金属离子并生成沉淀去除的新型荧光淬灭剂,以4-氨基-3,5-二(2-羟基苯基)-1,2,4-三唑[NH2C2N3(C6H4OH)2]为配体,合成重金属(Co,Cr,Mn,Ni)配合物,通过IR,1H NMR,13C NMR,MS和元素分析等确认其配位方式和结构,并测试了配合物的热重、紫外和荧光淬灭性能.结果表明:此类金属配合物热稳定性较好,Mn和Ni配合物高温下分解为氧化物;配合物的紫外吸收强度较配体有所减弱;配体荧光与重金属离子配位后发生淬灭,说明重金属离子Co,Cr,Mn,Ni是1,2,4-三唑配体优良的荧光淬灭剂,可通过配位生成沉淀去除.     

顺—1,2—二苯基—1,2—二巯基乙烯金属螯合物的合成

通过苯偶姻,对二甲氨基苯偶姻分别合成了相应的顺－１,２－二苯基－１,２－二巯基乙烯、顺－１－苯基－２－对二甲氨基苯基－１,２－二巯基乙烯及其各自与氯化镍反应形成的螯合物。     

Okadaxanthin,a novel C50-carotenoid from a bacterium,Pseudomonas sp. KK10206C associated with marine sponge,Halichondria okadai

To study the origins of biologically active substances in marine sponges, a carotenoid produced by a marine bacterium,Pseudomonas sp. strain number KK10206C, which was associated with a marine sponge,Halichondra okadai, was investigated. A visible absorption spectrum-guided isolation procedure led to the isolation of a novel C₅₀-carotenoid, okadaxanthin. Its structure, 2,2-bis(4-hydroxy-2-methyl-2-butenyl)-,-carotene, was elucidated mainly by spectroscopic methods. Okadaxanthin turned out to be a potent singlet oxygen quencher, approximately 10 times as strong as -tocopherol.     

玉竹(Polygonatum odoratum(Mill.) Druce)凝集素的荧光淬灭研究

百合科植物玉竹(Polygonatum odoratum(Mill.)Druce)的根状茎经生理盐水浸取、硫酸铵分级沉淀、CM-Sepharose柱离子交换层析和Sephacryl S-200凝胶过滤,得到经SDS-PAGE检测为14.2kD的单一蛋白条带的玉竹凝集素(Polygonatum odoratumlectin,简称POL).荧光淬灭剂丙烯酰胺、KI和CsCl对POL的内源荧光淬灭研究表明它们对凝集素分子荧光的淬灭过程属动态淬灭机制.其中玉竹凝集素中Trp残基对中性淬灭剂丙烯酰胺的可接近程度达到