Synthesis and biological evaluation of heteroarylnitrile derivatives for motile ciliogenesis

Motile cilia play a critical role in maintaining tissue homeostasis by driving fluid movement and clearing inhaled particles or pathogens. Dysfunction of these organelles underlies a range of ciliopathies, most notably affecting the respiratory system. Building on previous studies that identified molecules promoting motile cilia formation, we tried to discover novel small molecules that enhance motile ciliogenesis. To this end, we conducted a phenotype-based high-throughput screen using a Tg(foxj1a:eGFP) zebrafish reporter line, which led to the identification of a new chemotype hit. Subsequent structure–activity relationship (SAR) studies resulted in the development of compound 19b , which promoted motile cilia formation in zebrafish embryos. Its efficacy was further validated in ex vivo air–liquid interface (ALI) cultures of mouse tracheal epithelial cells, where treatment with 19b significantly increased the number of multiciliated cells. These findings suggest that compound 19b is a useful chemical probe for studying ciliogenesis and a potential lead for therapeutic development in motile ciliopathies. • Motile cilia play a vital role in fluid flow regulation, essential for development and homeostasis. • Dysregulation in ciliogenesis and cilia length leads to ciliopathies, highlighting the urgent need for new therapeutic drugs. • Compound 19b, identified through zebrafish HTS screening, significantly promotes foxj1a activity and motile cilia regeneration. • 19b shows dose-dependent efficacy and enhances MCC formation, positioning it as a promising candidate for treating motile ciliopathies.