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21.
目前有大量关于全程电荷匹配设计肽的应用的研究,但是关于半程电荷匹配设计肽作为药物的应用研究却未见报道.本文对新型设计的半程电荷匹配肽P9(AC-Pro-Ser-Phe-Asn-Phe-Lys-Phe-Glu-Pro-NH2)的研究发现,P9可以成功地将作为疏水药物模型的芘稳定悬浮于水溶液中.大豆卵磷脂微囊被用以模拟细胞膜.荧光数据显示芘可以借助P9的包埋作用以晶体状态存在于水溶液中.并且当包埋体加入到脂质体微囊体系中时,芘可以从P9的包埋体系中以分子形态释放到膜的脂质层内.实验发现当包埋于芘上的P9较多,包埋壁较厚,芘的释放速度相对变缓.我们可以利用这一特性,通过调节加入的P9的浓度来控制包埋于芘上P9的厚度,从而控制芘的释放速率.研究表明,具有半程电荷匹配性质的P9肽可以作为运载疏水药物的载体. 相似文献
22.
Oxonium ylide intermediates generated fromα-diazocarbonyl compounds and water were trapped by Zn(Ⅱ)-activatedα-dicarbonyl compounds.The reaction gaveα,β-dihydroxyl acid derivatives in moderate yield. 相似文献
23.
Click chemistry was applied to immobilize L-proline derivative onto azide-modified silica gel to give a novel chiral stationary phase(denoted as click-CSP) for ligand exchange chromatography.The developed protocol combines the benefits of operational simplicity,exceptionally mild conditions and high surface loadings.The enantioselectivityαof some DL-amino acids on the click-CSP were found to be in the range from 1.13 to 3.46.The chromatographic resolutions of some DL-amino acids and the stability study f... 相似文献
24.
Qing Han Li 《中国化学快报》2009,20(7):793-796
Six new asymmetric thiocarbonohydrazones 3a-3f were synthesized from following steps:firstly hydrazine hydrate reacted with carbon disulfide to form thiocarbonohydrazide(1) under microwave irradiation.Then compound(1) reacted with ketone and different aldehydes step by step to give 3a-3f with excellent yields under solvent-free conditions using microwave irradiation.Their structures have been determined by elemental analysis,IR,MS and ~1H NMR data. 相似文献
25.
A novel poly(ethylene glycol)(PEG) analogue composed of aliphatic polyester backbone and pendant oligo(ethylene glycol) short chains is reported.The PEG analogue is a copolymer synthesized by ring-opening alternating copolymerization of succinic anhydride with 2-((2-(2-metho xyethoxy)ethoxy)methyl)oxirane.The structure of the copolymer was confirmed by ~1H NMR spectrum.The effects of the monomer feed ratio on the copolymerization were studied and the polymerization mechanism was given.The PEG analogue di... 相似文献
26.
An efficient and simple method for the synthesis of new chiral aromatic amide molecular tweezers by irradiation with microwave under solvent-free conditions has been developed.Its main advantages are short reaction times.good conversions and the environmentally friendly nature of the process. 相似文献
27.
A new zinc acetate catalyst which was prepared from modified activated carbon exhibited extreme activity towards the synthesis of vinyl acetate.The activated carbon was modified by nitric acid,vitriol and peroxyacetic acid(PAA).The effect on specific area, structure,pH and surface acidity groups of carriers by modification was discussed.Amount of carbonyl and carboxyl groups in activated carbon was increased by peroxyacetic acid treatment.The productivity of the new catalyst was 14.58%higher than that of... 相似文献
28.
Juan Huang Jian Wei Wang Tao Gong Zhi Rong Zhang *Key Laboratory of Drug Targeting Ministry of Education West China School of Pharmacy Sichuan University Chengdu China 《中国化学快报》2007,(3)
To enable insulin as multi-drug carrier, we designed and synthesized dendritic linker molecule bearing three 5-Fluorouracil residues at the branch ends. The new conjugate showed excellent water solubility. The stabilities under different conditions were investigated. The results showed that the conjugate was a potential prodrug to release free 5-Fu. 相似文献
29.
本文采用一维流体模型导出了慢波介质自由电子激光器的线性色散方程,建立了电子和波相互作用的同向回旋同步机理和反向回旋同步机理. 相似文献
30.
本文对CCD摄象技术、等离子体诊断和脉冲辐射摄影的国内外最新发展作了评述,并涉及到在高技术领域的应用。 相似文献