Synthesis and structure-activity relationships of 5-phenyloxazole-2-carboxylic acid derivatives as novel inhibitors of tubulin polymerization

  • Bioorg Med Chem Lett. 2021 May 15:40:127968. doi: 10.1016/j.bmcl.2021.127968.
Ruiqiang Zhang  1 Hualong Mo  1 Yan-Yan Ma  2 Deng-Gao Zhao  3 Kun Zhang  2 Tingwen Zhang  1 Xuecheng Chen  1 Xi Zheng  1
Affiliations
  • 1. School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529020, China.
  • 2. School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529020, China; International Healthcare Innovation Institute (Jiangmen), Jiangmen 529040, China.
  • 3. School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529020, China; International Healthcare Innovation Institute (Jiangmen), Jiangmen 529040, China. Electronic address: [email protected].
Abstract

A series of 5-phenyloxazole-2-carboxylic acid derivatives were synthesized, and their structure-activity relationships (SARs) were studied. N,5-diphenyloxazole-2-carboxamides 6, 7, and 9, which mimicked ABT751, showed improved cytotoxicity compared with ABT751. Compound 9 exhibited the highest antiproliferative activities against Hela A549, and HepG2 Cancer cell lines, with IC50 values of 0.78, 1.08, and 1.27 μM, respectively. Furthermore, compound 9 showed selectivity for human Cancer cells over normal cells, and this selectivity was greater than those of ABT751 and colchicine. Preliminary mechanism studies suggested that compound 9 inhibited tubulin polymerization and led to cell cycle arrest at G2/M phase. Molecular docking studies indicated that compound 9 bound to the colchicine binding site of tubulin. Our findings provided insights into useful SARs for further structural modification of inhibitors of tubulin polymerization.

Keywords
ABT751; Cytotoxicity; Oxazole; Structure–activity relationships; Tubulin polymerization.