ChEBI: Idelalisib is a member of the class of quinazolines that is 5-fluoro-3-phenylquinazolin-4-one in which the hydrogen at position 2 is replaced by a (1S)-1-(3H-purin-6-ylamino)propyl group. used for for the treatment of refractory indolent non-Hodgkin's lymphoma and relapsed chronic lymphocytic leukemia. It has a role as an antineoplastic agent, an apoptosis inducer and an EC 2.7.1.137 (phosphatidylinositol 3-kinase) inhibitor. It is a member of purines, an organofluorine compound, a member of quinazolines, an aromatic amine and a secondary amino compound.NCI Thesaurus (NCIt): Idelalisib is an orally bioavailable, small molecule inhibitor of the delta isoform of the 110 kDa catalytic subunit of class I phosphoinositide-3 kinase (PI3K) with potential immunomodulating and antineoplastic activities. Idelalisib inhibits the production of the second messenger phosphatidylinositol-3,4,5-trisphosphate (PIP3), preventing the activation of the PI3K signaling pathway and inhibiting tumor cell proliferation, motility, and survival. Unlike other isoforms of PI3K, PI3K-delta is expressed primarily in hematopoietic lineages. The targeted inhibition of PI3K-delta is designed to preserve PI3K signaling in normal, non-neoplastic cells.