Antimony salt-promoted cyclization facilitating on-DNA syntheses of dihydroquinazolinone derivatives and its applications

DNA-encoded chemical libraries technology has become a novel approach to finding hit compounds in early drug discovery. The chemical space in a DEL would be expanded to realize its full potential, especially when integrating privileged scaffold dihydroquinazoline that has demonstrated a variety of diverse bioactivities. Driven by the requirement of parallel combinatorial synthesis, we here report a facile synthesis of on-DNA dihydroquinazolinone from aldehyde and anthranilamide. This DNA-compatible reaction was promoted by antimony trichloride, which has been proven to accelerate the reaction and improve conversions. Notably, the broad substrate scope of aldehydes and anthranilamides was explored under the mild reaction condition to achieve moderate-to-excellent conversion yields. We further applied the reaction into on-DNA macrocyclization, obtaining macrocycles embedded dihydroquinazolinone scaffold in synthetically useful conversion yields.