Discovery of 2-methoxy-3-phenylsulfonamino-5-(quinazolin-6-yl or quinolin-6-yl)benzamides as novel PI3K inhibitors and anticancer agents by bioisostere

• Benzamide replace the pyridine ring in GSK2126458 to produce a novel scaffold of PI3K inhibitor.
• Title compounds were synthesized.
• Most of compounds displayed antiproliferative activity.
• Compound 1a blocks PI3K/AKT/mTOR pathway and exhibits anticancer effect.

2-Substituted-3-sulfonamino-5-(quinazolin-6-yl or quinolin-6-yl)benzamides have been proposed as novel structures of PI3K inhibitors and anticancer agents based on bioisostere. In the present study, 2-substituted-3-sulfonamino-5-(4-morpholinoquinazolin-6-yl)benzamides and 2-methoxy-3-sulfonamino-5-(4-morpholinoquinolin-6-yl)benzamides were synthesized. Their antiproliferative activities in vitro were evaluated via MTT assay against four human cancer cell lines, including A549, HCT-116, U-87 MG and KB. The SAR of the title compounds was preliminarily discussed. Compound 1a with potent antiproliferative activity was tested for its inhibitory activity against PI3K and mTOR and its effect on the AKT and p-AKT473. The anticancer effect of 1a was evaluated in established nude mice U-87 MG xenograft model. The results suggest that compound 1a can significantly inhibit PI3K/AKT/mTOR pathway and tumor growth. These findings strongly support the assumption that title compounds are potent PI3K inhibitors and anticancer agents.

The structure of benzamide can replace the complex of the pyridine in GSK2126458 with water molecule to design novel PI3K inhibitors and anticancer agents based on bioisostere.Figure optionsDownload as PowerPoint slide