ARQ 621

• CAT Number: I002796
• CAS Number: 1095253-39-6
• Molecular Formula: C28H24Cl2FN5O2
• Molecular Weight: 552.43
• Purity: ≥95%
• Synonyms: N-(3-aminopropyl)-N-[(1R)-1-(3-anilino-7-chloro-4-oxoquinazolin-2-yl)but-3-ynyl]-3-chloro-2-fluorobenzamide
• InChI: InChI=1S/C28H24Cl2FN5O2/c1-2-8-24(35(16-7-15-32)27(37)21-11-6-12-22(30)25(21)31)26-33-23-17-18(29)13-14-20(23)28(38)36(26)34-19-9-4-3-5-10-19/h1,3-6,9-14,17,24,34H,7-8,15-16,32H2/t24-/m1/s1
• InChIKey: UPJSUQWHUVLLNW-XMMPIXPASA-N
• SMILES: C#CC[C@H](C1=NC2=C(C=CC(=C2)Cl)C(=O)N1NC3=CC=CC=C3)N(CCCN)C(=O)C4=C(C(=CC=C4)Cl)F

ARQ 621（Cat No.:I002796）is a potent, selective inhibitor of the molecular motor protein Eg5 (also known as kinesin spindle protein, KSP), which is essential for mitotic spindle assembly during cell division. By blocking Eg5 function, ARQ 621 induces mitotic arrest and apoptosis in rapidly proliferating tumor cells. This mechanism makes it a promising investigational compound in oncology, particularly for cancers resistant to microtubule-targeting agents. In research, ARQ 621 is widely used to study mitotic regulation, cell cycle progression, and the therapeutic potential of kinesin inhibitors in targeted cancer therapy.