A selective, high affinity , orally bioavailable 5-HT2B receptor antagonist. RS-127445 was found to have nanomolar affinity for the 5-HT2B receptor (pKi = 9.5) and 1,000 fold selectivity for this receptor as compared to numerous other receptor and ion channel binding sites including the closely related 5-HT2A and 5-HT2C receptors. In isolated human cells, RS-127445 exbhited an IC50 greater than 10uM. Solubility:DMSO or EtOHPrimary Target:5-HT2BStorage and Stability:May be stored at 4°C. For long-term storage, aliquot and store at 4°C. Do not freeze. For maximum recovery of product, centrifuge the original vial prior to removing the cap. Further dilutions can be made in assay buffer.