Quarfloxin  (Synonyms: CX-3543)

Quarfloxin (CX-3543), a fluoroquinolone derivative with antineoplastic activity, targets and inhibits RNA pol I activity, with IC₅₀ values in the nanomolar range in neuroblastoma cells. Quarfloxin disrupts the interaction between the nucleolin protein and a G-quadruplex DNA structure in the ribosomal DNA (rDNA) template^[1].

RNA pol I^[1].

Quarfloxin (CX-3543) effectively inhibits the growth of neuroblastoma cells in vitro. MNA (or high c-Myc) and wt-TP53 cell lines are found to be more sensitive to Quarfloxin. Quarfloxin and induces DNA damage, p53 signaling, cell death, and cell cycle arrest in neuroblastoma cell lines^[1].
Solution in vitro: Quarfloxin is suspended in DMSO to a stock of 10 mM^[1].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

604.67

C₃₅H₃₃FN₆O₃

865311-47-3

Solid

Light yellow to yellow

O=C(C1=CN2C3=C(C(N4CC(C5=NC=CN=C5)CC4)=C(F)C=C3C1=O)OC6=CC7=CC=CC=C7C=C26)NCC[C@H]8N(C)CCC8

Room temperature in continental US; may vary elsewhere.

* Please refer to the solubility information to select the appropriate solvent. Once prepared, please aliquot and store the solution to prevent product inactivation from repeated freeze-thaw cycles.
Storage method and period of stock solution: -80°C, 2 years; -20°C, 1 year. When stored at -80°C, please use it within 2 years. When stored at -20°C, please use it within 1 year.

* Note: If you choose water as the stock solution, please dilute it to the working solution, then filter and sterilize it with a 0.22 μm filter before use.

• [1]. Hald ØH, et al. Inhibitors of ribosome biogenesis repress the growth of MYCN-amplified neuroblastoma. Oncogene. 2018 Dec 12.  [Content Brief]