SB742457 is a selective antagonist of 5-HT6 receptor with a pKi value of 9.63 [1].
SB742457 has been found to be a highly selective 5-HT6 receptor antagonist with high affinity to human 5-HT6 receptor. The pKi value of SB742457 is 9.63. In addition, because of the orally bioavailable, SB742457 has been reported to promote brain penetration in rat over previously developed compounds. Besides, subchronic daily oral pre-dosing of SB742457 (1.5mg/kg) has been noted to significantly induce by the cholinergic antagonist scopolamine (0.5mg/kg) in a novel object recognition paradigm. Apart from these, acute oral treatment of SB742457 has been found to induce significant increases levels of glutamate and acetylcholine in extracellular in the medial prefrontal cortex of freely moving rats [1].
Reference:
[1] Aaron T. T. Chuang, Andrew Foley, Perdita L. Pugh, David Sunter, Xin Tong, Ciaran Regan, Lee A. Dawson, Andrew D. Medhurst, Neil Upton.5-HT6 receptor antagonist SB-742457 as a novel cognitive enhancing agent for Alzheimer’s disease. Alzheimer's & Dementia: The Journal of the Alzheimer's Association Volume 2, Issue 3, Supplement, Pages S631–S632, July 2006