TTDA衍生物及其金屬錯合物之合成、物化特性及與人類血清蛋白鍵結研究

Synthesis and Physicochemical Characterization of TTDA-like Complexes and Their Interaction with Human Serum Albumin

歐明鴻(Ming-Hung Ou)

指導教授 ： 王雲銘

高雄醫學大學/藥學院/藥學研究所/博士(2007年)

https://doi.org/10.6832/KMU.2007.00139

摘要

本論文成功合成了兩個含苯氧甲基之TTDA （3,6,10-tris (carboxymethyl)-3,6,10-triazadodecanedioic acid）衍生物，TTDA-BOM與TTDA-N΄-BOM，一個單醯胺TTDA衍生物，TTDA-N-MOBA及兩個雙醯胺TTDA衍生物，TTDA-BMA與TTDA-BBA。雖然TTDA單醯胺及雙醯胺衍生物其金屬錯合物之穩定常數低於[Gd(TTDA)]2?{與[Gd(DTPA)]2?{，但其釓金屬錯合物對鋅(II)與銅(II)之選擇常數卻高於TTDA與DTPA。而在與鋅金屬之動力學穩定常數測定中，[Gd(TTDA-BOM)]2?{及[Gd(TTDA-N΄-BOM)]2?{明顯的比[Gd(DTPA- BMA)]來的穩定。TTDA-BOM、TTDA-N΄-BOM、TTDA-N-MOBA、TTDA-BMA及TTDA-BBA之釓金屬錯合物在20 MHz、37 ?aC下，求得其弛緩率（r1）分別為4.42、4.44、4.23、3.92及4.41 mM?{1 s?{1。釓金屬錯合物之內層水分子交換速率（kex298）及分子轉動相關時間（?豩）則利用9.4 T之17O NMR求得。實驗結果顯示[Gd(TTDA-BOM)]2?{及[Gd(TTDA-N΄-BOM)]2?{之內層水分子交換速率分別為117 ?e 106及131 ?e 106 s?{1，其值遠高於[Gd(BOPTA)]2?{（3.45 ?e 106 s?{1)及[Gd(DTPA)]2?{（4.1 ?e 106 s?{1），而近似於[Gd(TTDA)]2−（146 ?e 106 s?{1）。而TTDA單醯胺衍生物，[Gd(TTDA-MOBA)]?{，其kex298值為29.1 ?e 106 s?{1，大約是[Gd(TTDA)]2−之kex298值的1/5。另一方面，TTDA雙醯胺衍生物，[Gd(TTDA-BMA)]與[Gd(TTDA-BBA)]，其kex298值分別為15.2 ?e 106 s?{1及15.6 ?e 106 s?{1，大約是[Gd(TTDA)]2−之kex298值的1/10。另外，由17O NMR實驗結果顯示，[Gd(TTDA-BOM)]2?{、[Gd(TTDA-N΄-BOM)]2?{、[Gd(TTDA-MOBA)]?{、[Gd(TTDA-BMA)]及[Gd(TTDA-BBA)]之分子轉動相關時間分別為119、125、157、119及187 ps，其值高於[Gd(DTPA)]2?{（103 ps）與[Gd(TTDA)]2−（104 ps）。而在螢光探針置換實驗中，[Gd(TTDA-BOM)]2–及[Gd(TTDA-N΄-BOM)]2–與dansylsarcosine在HSA中抑制常數(Ki)分別為1900及1600 ?嵱。這些結果顯示[Gd(TTDA-BOM)]2–及[Gd(TTDA-N΄-BOM)]2–與HSA在次區域IIIA形成一個較弱的鍵結。在[Gd(TTDA-BOM)]2–、[Gd(TTDA-N΄-BOM)]2–及[Gd(TTDA-BBA)]與HSA形成非共價性鍵結實驗中，分別求得鍵結常數（KA）為4.6 ?e 102、5.4 ?e 102及1.0 ?e 104 M?{1，而鍵結弛緩率（ ）分別為65.8、61.5及52.0 mM?{1 s?{1。最後，由弛緩率研究與超過濾實驗發現，[Gd(TTDA-BOM)]2–、[Gd(TTDA-N΄-BOM)]2–及[Gd(TTDA-BBA)]與HSA之鍵結弛緩率高於商業化之磁振造影對比劑MS-325。

關鍵字

釓金屬錯合物 ； 磁振造影對比劑 ； 水交換速率 ； 人類血清蛋白 ； 鍵結弛緩率

並列摘要

Two novel derivatives of TTDA (3,6,10-tri(carboxymethyl)-3,6,10- triazadodecanedioic acid), TTDA-BOM and TTDA-N'-BOM, which have a benzyloxymethyl group, were synthesized. Moreover, one monoamide and two bis(amide) derivatives of TTDA, TTDA-N-MOBA, TTDA-BMA and TTDA-BBA, were synthesized. The values of the stability constant of Gd(III) complexes with TTDA-mono- and bis(amide) are significantly lower than those of [Gd(TTDA)]2?{ and [Gd(DTPA)]2?{, but the selectivity constants of these ligands for Gd(III) over Zn(II) and Cu(II) are slightly higher than those of TTDA and DTPA. On the other hand, as measured by the Zn(II) transmetallation process, the kinetic stability of [Gd(TTDA-BOM)]2?{ and [Gd(TTDA-N'-BOM)]2?{ is significantly higher than that of [Gd(DTPA-BMA)]. In addition, the relaxivity (r1) values of [Gd(TTDA-BOM)]2?{, [Gd(TTDA-N'-BOM)]2?{, [Gd(TTDA-MOBA)]?{, [Gd(TTDA-BMA)] and [Gd(TTDA-BBA)] using 20 MHz relaxometer at 37.0 ?b 0.1 ?aC were 4.42, 4.44, 4.23, 3.92 and 4.41 mM?{1 s?{1, respectively. 17O NMR longitudinal and transverse relaxation rates and chemical shifts were measured at variable temperature at 9.4 T magnetic fields for aqueous solutions of these Gd(III) complexes. The water exchange rate (kex298) values for [Gd(TTDA-BOM)]2− (117 ?e 106 s?{1) and [Gd(TTDA- N'-BOM)]2?{ (131 ?e 106 s?{1) are significantly higher than those of [Gd(DTPA)]2− (4.1 ?e 106 s?{1) and [Gd(BOPTA)]2− (3.45 ?e 106 s?{1), and are similar to that of [Gd(TTDA)]2− (146 ?e 106 s?{1). For the TTDA-monoamide, [Gd(TTDA-MOBA)]?{, the kex298 value is 29.1 ?e 106 s?{1, about one-fifth of the water exchange rate on [Gd(TTDA)]2−. Furthermore, for the TTDA-bis(amide), [Gd(TTDA-BMA)] and [Gd(TTDA-BBA)], the kex298 values are 15.2 ?e 106 s?{1 and 15.6 ?e 106 s?{1, respectively, about one-tenth of the water exchange rate on [Gd(TTDA)]2−. The rotational correlation time (?豩) values for [Gd(TTDA-BOM)]2− (119 ps), [Gd(TTDA-N'-BOM)]2?{ (125 ps), [Gd(TTDA-MOBA)]?{ (157 ps), [Gd(TTDA-BMA)] (119 ps) and [Gd(TTDA-BBA)] (187 ps) are higher than those of [Gd(DTPA)]2− (103 ps) and [Gd(TTDA)]2− (104 ps). Fluorescent probe displacement studies exhibit that [Gd(TTDA-BOM)]2– and [Gd(TTDA-N'-BOM)]2– can displace dansylsarcosine from HSA with inhibition constants (Ki) of 1900 ?嵱 and 1600 ?嵱, respectively; however, they are not able to displace warfarin. These results indicate that [Gd(TTDA-BOM)]2– and [Gd(TTDA-N'-BOM)]2– have a weak binding to subdomain IIIA on HSA. In addition, binding constant (KA) values for [Gd(TTDA-BOM)]2?{/HSA, [Gd(TTDA-N’-BOM)]2?{/HSA and [Gd(TTDA-BBA)]/HSA are 4.6 ?e 102, 5.4 ?e 102 and 1.0 ?e 104 M?{1, respectively; and bound relaxivity ( ) values are 65.8, 61.5 and 52.0 mM?{1 s?{1, respectively. Finally, from the relaxivity and ultrafiltration studies, it is clear that the bound relaxivity (r1b) values of [Gd(TTDA-BOM)]2–, [Gd(TTDA-N'-BOM)]2– and [Gd(TTDA-BBA)] are higher than that of MS-325 which is commercial MRI contrast agent.

並列關鍵字

Gadolinium(III) complexes ； MRI contrast agent ； Water exchange rate ； Human serum albumin ； Bound relaxivity

參考文獻

1. Merbach, A. E.; Toth, E., The Chemistry of Contrast Agents in Medical Magnetic Resonance Imaging. Wiley: New York, 2001.

2. Bloch, F.; Hansen, W. W.; Packard, M., Phys. Rev. 1946, 69, 127-127.

3. Lauterbur, P. C., Nature 1973, 242, 190-191.

4. Banci, L.; Bertini, I.; Luchinat, C., Nuclear and Electron Relaxation : the Magnetic Nucleus-unpaired Electron Coupling in Solution. VCH: Weingeim: New York, 1991.

5. Caravan, P.; Ellison, J. J.; McMurry, T. J.; Lauffer, R. B., Chem. Rev. 1999, 99, 2293-2352.