抗肿瘤环八肽Samoamide A的固相合成及其细胞毒性

Synthesis and Cytotoxicity of Hexapeptide Samoamide A

采用Fmoc固相合成法,以2-氯三苯甲基氯(CTC)树脂为固相载体,Fmoc保护的氨基酸为原料,合成了环八肽Samoamide A,其结构经~1H NMR,^(13)C NMR和LC-MS(EI)确证。研究了反应溶剂、缩合剂、切割条件和pH对Samoamide A收率的影响。结果表明:合成Samoamide A的最佳条件为:60%DCM/DMF为溶剂,O-苯并三氮唑-N,N,N′,N′-四甲基脲四氟硼酸(TBTU)为缩合剂,TFA/EDT/PhOH/H_2O/硫茴香醚为切割试剂(80/2.5/7.5/5/5,V/V/V/V/V), pH 8.0,总收率54.5%。采用MTT法研究了Samoamide A的细胞毒性。结果表明:Samoamide A浓度为50.0μg·mL^(-1)时,4T1细胞的存活率为20.79%。

The hexapeptide Samoamide A was synthesized by Fmoc solid phase synthetic method, using 2-chlorotrityl chloride(CTC) resin as solid phase carrier and Fmoc protecting amino acid as material. The influence of coupling solvents, coupling reagents, cleavage conditions and pH on the yield of Samoamide A was investigated. The structure was confrimed by 1 H NMR, 13 C NMR and LC-MS(EI). The optimized protocol was ascertained: 60%DCM/DMF as the coupling solvent, TBTU as the coupling reagent, TFA/EDT/PhoH/H 2 O/thioanisole=80/2.5/7.5/5/5 as the cleavage reagent and pH 8.0. The yield reached 54.5%. The cytotoxicity of the synthetic product were evaluated through MTT assays against various human cancer cell lines. the results showed that when the concentration of Samoamide A reached 50.0 μg·mL^-1 , the survival rate of 4T1 cells was only 20.79%.