Background:

5-HT3 antagonist 2 is a 5-HT3 receptor antagonist.

5-HT3 antagonist 2 is from the reference compound 21k[1].

[1]. Swain CJ, et al. Novel 5-HT3 antagonists: indol-3-ylspiro(azabicycloalkane-3,5’(4’H)-oxazoles). J Med Chem. 1992 Mar 20;35(6):1019-31.