苯丙氨酸衍生物的合成、~(18)F标记及其生物学评价

应用正电子核素18F对4-(2-氟乙氧基)苯甲酰基苯丙氨酸甲酯(Methyl-2-(4-(2-fluoroethoxy)benzamido)-3-phenylpropanoate,MFBPA)及4-(2-氟乙氧基)苯甲酰基苯丙氨酸(2-(4-(2-fluoroethoxy)benzamido)-3-phenylpropanoic Acid,FBPA)进行标记,分别得到18F-MFBPA和18F-FBPA,并初步研究了18F-MFBPA和18F-FBPA的体外、体内稳定性和生物分布1。8F-MFBPA的标记率为23%~41%1。8F-MFBPA和18F-FBPA经HPLC分析,放化纯度均99%。分别随机选取20只荷S180瘤昆明小鼠,经尾静脉注射18F-MFBPA或18F-FBPA,计算主要组织中的放射性摄取率,对18F-MFBPA和18F-FBPA与18F-FET和18F-FDG的生物分布进行比较。结果表明,18F-FBPA更具有良好的生物性质,有望成为恶性肿瘤的正电子显像剂。

Synthesis and Biological Evaluation of 2-amino-3-phenylpropanoic Acid Derivatives Labeled With 18F

Methyl-2-（4-（2-fluoroethoxy） benzamido）-3-phenylpropanoate（MFBPA） and its hydrolysis product 2-（4-（2-fluoroethoxy）benzamido）-3-phenylpropanoic acid（FBPA） were synthesized and labeled by 18F.To evaluate applicability of ^18F-MFBPA and ^18F-FBPA in detecting malignant fibrosarcoma,some studies were carried on biodistribution,stabilities in vitro or in vivo and autoradiophotography.After 60 min of intravenous injection the accumulations of ^18F-MFBPA and ^18F-FBPA in tumor,muscle,blood and brain were 0.78±0.02,0.72±0.04,0.66±0.07,0.38±0.03%ID/g and 0.95±0.05,0.64±0.06,0.65±0.04,0.34±0.01%ID/g,respectively.Their ratios of tumor to muscle,tumor to blood,and tumor to brain were 1.18,1.08,2.05 and 1.46 1.48,2.79,respectively.The results indicated that ^18F-FBPA might have more potential to be PET imaging agent.