Abstract
Using HBTU based amide bond forming reaction and Combinatorial Chemistry could build libraries of Uridine/ara-Uridine 5’ derivatives analogs in solution phase. Then the process of cell assay（MTT assay）in situ in the microtiter plate was carried out without isolation or purification. The potent structures of Anti-cancer drug were screened rapidly by the combination of library and in situ cytotoxic assay. Our scheme of organic synthesis was following literature to get the 5’-amino,deoxy Uridine. And some steps were changed for ara-Uridine case： 1. ara-Uridine 5'OH and 2',3'OH were protected by TBDMS and Ac. 2. After 5’ TBDMS was removed, a leaving group tosyl (TsO-) was made on 5'OH. 3. 5’ tosyl was replaced by azido(N3) and then 2',3' Ac was removed. 4. 5’azido was reduced by hydrogen gas and Pd/C. 5. 5’-amino,deoxy ara-Uridine was gotten. When setting up the library, we found that the amide derivatives from 2-Benzoylbenzoic acid analog coupling with amine would cyclize. In cytotoxic assay, human lung cancer cell line A549（Cisplatin, IC50＝12μM）and breast cancer cell line MCF7（Cisplatin, IC50＝19μM）were adherent and selected for testing. According to the result of in situ cytotoxic screening with HBTU based amide bond forming reaction, the active compounds were purified for the next assay：the amide derivative from Fenbufen coupling with n-butyl amine was 100μM（IC50 value）in both Cell lines and from Lauric acid coupling with 5’-amino; deoxy Uridine was 100μM（IC50 value）in MCF7 but seemed no toxicity in A549. It showed that the combination of library and in situ cell assay received fundamental success.