首页> 外文学位 >Part A: Coordination of pyridine and pyridine-type ligands to cobalt(II)- and cobalt(III)-substituted Keggin and Dawson-type heteropolyanions. Part B: Encapsulation of various heteropolyanions in artificial phospholipid vesicles: Effects of size, charge, and polarity on encapsulation efficiency.

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Part A: Coordination of pyridine and pyridine-type ligands to cobalt(II)- and cobalt(III)-substituted Keggin and Dawson-type heteropolyanions. Part B: Encapsulation of various heteropolyanions in artificial phospholipid vesicles: Effects of size, charge, and polarity on encapsulation efficiency.

机译：A部分：吡啶和吡啶型配体与钴（II）和钴（III）取代的Keggin和Dawson型杂多阴离子的配位。 B部分：在人工磷脂囊泡中包裹各种杂多阴离子：大小，电荷和极性对包裹效率的影响。

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Cobalt derivatives of the lacunary heteropolytungstates ({dollar}alphasb1{dollar}-{dollar}rm Psb2Wsb{lcub}17{rcub}Osb{lcub}61{rcub}rbracksp{lcub}10-{rcub}{dollar} (I), ({dollar}alphasb2{dollar}-{dollar}rm Psb2Wsb{lcub}17{rcub}Osb{lcub}61{rcub}rbracksp{lcub}10-{rcub}{dollar} (II), ({dollar}alpha{dollar}-{dollar}rm SiWsb{lcub}11{rcub}Osb{lcub}39{rcub}rbracksp{lcub}8-{rcub}{dollar} (III), and ({dollar}alpha{dollar}-{dollar}rm PWsb{lcub}11{rcub}Osb{lcub}39{rcub}rbracksp{lcub}7-{rcub}{dollar} (IV), have been examined as possible precursors to surface-modified heteropolyanions stable at biological pH. Addition of excess pyridine to solutions of the Co(II) derivatives yields NMR signals for free and complexed pyridine from which the rates of ligand exchange can be determined. At 24{dollar}spcirc{dollar}C, these range from 9.2 s{dollar}sp{lcub}-1{rcub}{dollar} (III) to {dollar}rm1.6times10sp2 ssp{lcub}-1{rcub}{dollar} (IV).; Chemical or electrochemical oxidation of the aquacobalt(II) derivatives generates the corresponding Co(III) species which also undergo substitution by pyridine. The rates for this process at 30{dollar}spcirc{dollar}C are {dollar}rm3.0times10sp{lcub}-2{rcub} ssp{lcub}-1{rcub}{dollar} (I), {dollar}rm3.7times10sp{lcub}-4{rcub} ssp{lcub}-1{rcub}{dollar} (II), and {dollar}rm4.7times10sp{lcub}-4{rcub} ssp{lcub}-1{rcub}{dollar} (III). Complexes of the Co(III) derivative of (I) with pyridine, pyrazine, 4,4-bipyridyl (both 1:1 and 1:2 species), isonicotinic acid, and isonicotinoylglycylglycylethylester were isolated as cesium or guanidinium salts, and characterized by NMR, UV-vis and electrochemistry.; A procedure for the encapsulation of heteropolyanions in artificial phospholipid vesicles was developed. Vesicles with encapsulated heteropolyanions were found to be some 10-fold larger than "empty" vesicles. X-ray microprobe analysis and adsorption studies verified that the heteropolyanions were associated with the vesicles, and not with the liquid medium.; The relative fraction of dissolved heteropolyanion that was encapsulated (3-18% under standardized conditions) increased as the surface charge density (anion charge/anion volume) decreased, e.g. from {dollar}rmlbrack CoWsb{lcub}12{rcub}Osb{lcub}40{rcub}rbracksp{lcub}6-{rcub}{dollar} to {dollar}rmlbrack Psb2Wsb{lcub}18{rcub}Osb{lcub}62{rcub}rbracksp{lcub}6-{rcub}.{dollar} Further, heteropolyanions possessing distinct organic regions on their surfaces, such as {dollar}rmlbrack(BuSn)sb3(Psb2Wsb{lcub}15{rcub}Osb{lcub}59{rcub})rbracksp{lcub}9-{rcub},{dollar} had much higher encapsulation levels than expected from their charge to volume ratios.; Preliminary comparative experiments involving interactions of {dollar}rmlbrack(BuSn)sb3(Psb2Wsb{lcub}15{rcub}Osb{lcub}59{rcub})rbracksp{lcub}9-{rcub}{dollar} in solution and in phospholipid vesicles with wild-type breast cancer cells showed that the vesicle-encapsulated heteropolyanions were more effective at inhibiting cell growth than the aqueous solution of the same polyoxometalate. This difference demonstrated that encapsulation of heteropolyanions in phospholipid vesicles alters the interaction of heteropolyanions with cells.

机译：腔杂多钨酸盐（{dollar} alphasb1 {dollar}-{dollar} rm Psb2Wsb {lcub} 17 {rcub} Osb {lcub} 61 {rcub} rbracksp {lcub} 10- {rcub} {dollar}的钴衍生物，（{dollaralphasb2 {dollar}-{dollar} rm Psb2Wsb {lcub} 17 {rcub} Osb {lcub} 61 {rcub} rbracksp {lcub} 10- {rcub} {dollar}（II），（{dollar} alpha {dollar}-{dollar} rm SiWsb {lcub} 11 {rcub} Osb {lcub} 39 {rcub} rbracksp {lcub} 8- {rcub} {dollar}（III）和（{dollar} alpha {dollar} -{dollar} rm PWsb {lcub} 11 {rcub} Osb {lcub} 39 {rcub} rbracksp {lcub} 7- {rcub} {dollar}（IV）已作为表面改性杂多阴离子稳定在的可能前体进行了研究生物学pH值，将过量的吡啶加到Co（II）衍生物的溶液中可产生游离和络合吡啶的NMR信号，可从中确定配体交换的速率，在24 24spcirc {dol} C时，此范围为9.2 s {dollar} sp {lcub} -1 {rcub} {dollar}（III）到{dollar} rm1.6times10sp2 ssp {lcub} -1 {rcub} {dollar}（IV）.;钴的化学或电化学氧化（二）衍生es生成相应的Co（III）物种，该物种也将被吡啶取代。此过程的速率为30 {dollar} spcirc {dollar} C为{dollar} rm3.0×10sp {lcub} -2 {rcub} ssp {lcub} -1 {rcub} {dollar}（I），{dollar} rm3 .7times10sp {lcub} -4 {rcub} ssp {lcub} -1 {rcub} {dollar}（II）和{dollar} rm4.7times10sp {lcub} -4 {rcub} ssp {lcub} -1 {rcub} {美元}（III）。分离（I）的Co（III）衍生物与吡啶，吡嗪，4,4-联吡啶基（1：1和1：2两种），异烟酸和异烟酰氨基糖基缩水甘油基乙基酯的络合物，以铯盐或胍盐的形式分离，并通过NMR，UV-vis和电化学。开发了在人工磷脂囊泡中包裹杂多阴离子的方法。发现具有包封的杂多阴离子的囊泡比“空”囊泡大约十倍。 X射线微探针分析和吸附研究证实杂多阴离子与囊泡有关，与液体介质无关。当表面电荷密度（阴离子电荷/阴离子体积）降低时，例如，包封的溶解的杂多阴离子的相对分数（在标准条件下为3-18％）增加。从{dollar} rmlbrack CoWsb {lcub} 12 {rcub} Osb {lcub} 40 {rcub} rbracksp {lcub} 6- {rcub} {dollar}到{dollar} rmlbrack Psb2Wsb {lcub} 18 {rcub} Osb {lcub} 62 {rcub} rbracksp {lcub} 6- {rcub}。{dollar}此外，杂多阴离子在其表面上具有不同的有机区域，例如{dollar} rmlbrack（BuSn）sb3（Psb2Wsb {lcub} 15 {rcub} Osb {lcub } 59 {rcub}）rbracksp {lcub} 9- {rcub}，{dollar}的封装水平比其电荷体积比预期的高得多。初步比较实验涉及溶液和磷脂囊中的{dol} rmlbrack（BuSn）sb3（Psb2Wsb {lcub} 15 {rcub} Osb {lcub} 59 {rcub}）rbracksp {lcub} 9- {rcub} {dollar}相互作用的初步比较实验用野生型乳腺癌细胞研究表明，囊泡包埋的杂多阴离子比同一种多金属氧酸盐的水溶液更能有效地抑制细胞生长。这种差异表明，杂多阴离子包囊在磷脂囊泡中会改变杂多阴离子与细胞的相互作用。

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作者
Samonte, Joseph Laurito.;
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作者单位

Georgetown University.;

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授予单位 Georgetown University.;
学科 Chemistry Inorganic.; Chemistry Biochemistry.; Health Sciences Oncology.; Health Sciences Pharmacy.
学位 Ph.D.
年度 1996
页码 168 p.
总页数 168
原文格式 PDF
正文语种 eng
中图分类无机化学;生物化学;肿瘤学;药剂学;
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专利

1. Derivatization of polyoxotungstates in aqueous solution. Exploration of the kinetic stability of cobalt(II)- and cobalt(III) derivatives of lacunary anions with pyridine and pyridine-type ligands [J] . Samonte JL., Pope MT. Canadian Journal of Chemistry . 2001,第5期

机译：水溶液中多氧钨酸盐的衍生化。含吡啶和吡啶型配体的阴阴离子钴（II）和钴（III）衍生物的动力学稳定性的探索
2. Derivatization of polyoxotungstates in aqueous solution. Exploration of the kinetic stability of cobalt(II)-and cobalt(III) derivatives of lacunary anions with pyridine and pyridine-type ligands [J] . Joseph L. Samonte, Michael T. Pope Canadian Journal of Chemistry . 2001,第5a6期

机译：水溶液中多氧钨酸盐的衍生化。具有吡啶和吡啶型配体的阴阴离子钴（II）和钴（III）衍生物的动力学稳定性的探索
3. Derivatization of polyoxotungstates in aqueous solution. Exploration of the kinetic stability of cobalt(II)- and cobalt(III) derivatives of lacunary anions with pyridine and pyridine-type ligands [J] . Samonte J.L., Pope M.T. Canadian Journal of Chemistry . 2001,第5期

机译：水溶液中多氧钨酸盐的衍生化。带有吡啶和吡啶型配体的阴阴离子的钴（II）和钴（III）衍生物的动力学稳定性的探索
4. Crystal structure of a CoII coordination polymer with a dipyridyl ligand: catena-polybis(nitrato-κ2OO′)cobalt(II)-μ-N-(pyridin-2-ylmethyl)pyridine-3-amine-κ3NN′:N′′ [O] . Suk-Hee Moon, Youngjin Kang, Ki-Min Park 2017

机译：具有二吡啶基配体的CoII配位聚合物的晶体结构：链状聚bis（nitrato-κ2OO）钴（II）-μ-N-（吡啶-2-基甲基基）吡啶-3-胺-κ3NN：N
5. Inequivalent coordination of thiosemicarbazone ligands in cobalt (III) and chromium (III) complexes [O] . Pramila Sonawane, Rajeev Chikate, Avinash Kumbhar, 1994

机译：在钴（III）和铬（III）络合物中不等价值协调硫代吡唑酮配体

Part A: Coordination of pyridine and pyridine-type ligands to cobalt(II)- and cobalt(III)-substituted Keggin and Dawson-type heteropolyanions. Part B: Encapsulation of various heteropolyanions in artificial phospholipid vesicles: Effects of size, charge, and polarity on encapsulation efficiency.

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