BADTPA偶联~(153)Sm,~(186)Re标记平阳霉素
LABELING OF PINGYANGMYCIN WITH ~(153)Sm AND ~(186)Re THROUGH THE CONJUGATION OF BADTPA
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摘要: 通过一步法合成二乙三胺五乙酸环二酸酐 (BADTPA)并与平阳霉素 (PLM )偶联 ,于室温制得DTPA PLM。在 pH为 4~ 6的沸水中进行153 Sm标记 ,反应 3min后制得产额高于 95 %的153 Sm DTPA PLM。采用亚锡还原法进行186Re标记 ,在 pH为 3~ 5的沸水中反应 30min制得产额高于 95 %的186Re DTPA PLM。两种标记物的稳定性很好 ,于室温下放置 4 8h后 ,其放化纯度仍高于 95 %。脂水分配系数表明 ,153 Sm DTPA PLM是亲水性的。动物体内分布实验结果表明 :153 Sm DTPA PLM的血液清除较快 ,主要通过肾脏代谢。正常鼠体内行为初试结果表明 :186Re DTPA PLM是一种可望用于肿瘤治疗的新型药物。Abstract: Pingyangmycin (PLM) is a homemade antibiotics mixture with bleomycin as its main constituent. 153 Sm or 186 Re is indirectly labeled to PLM via a conjugating chelator. Diethylenetramine penta acetic acid(DTPA)is chosen as the conjugator. The bicyclic anhydride of DTPA(BADTPA)is chosen as the conjugator. The bicyclic anhydride of DTPA(BADTPA)is coupled to PLM at room temperature to form a BADTPA PLM adduct. 153 Sm BADTPA PLM is prepared by boiling of aqueous 153 SmCl 3 and BADTPA solution mixture at pH=4~6 for 3 min. 186 Re is labeled to BADTPA PLM by reduction of 186 ReO - 4 with SnCl 2+Sn at 95 ℃ for 30 min in the presence of gluconic acid(pH=3~5). The yield in both cases in higher than 95%. The labeled compounds are stable for 48 h at least at room temperature. Their high hydrophilicity is demonstrated by their low partition coefficients between noctanol and water. The biodistribution of these labeled compounds in mice upon time is determined. The results indicate that these labeled compounds are principally excreted through blood kidney route.