Background:

HX 531 is an antagonist of the retinoid X receptor (RXR) with an IC50 value of 18 nM that inhibits 9-cis retinoic acid -induced transactivation of RXR.[1] It has been shown to reduce triglyceride content in white adipose tissue, skeletal muscle, and the liver of mice on a high fat diet.[2]

Reference:
[1]. Konta, T., Xu, Q., Furusu, A., et al. Selective roles of retinoic acid receptor and retinoid x receptor in the suppression of apoptosis by all-trans-retinoic acid. J. Biol. Chem. 276(16), 12697-12701 (2001).
[2]. Yamauchi, T., Waki, H., Kamon, J., et al. Inhibition of RXR and PPARγ ameliorates diet-induced obesity and type 2 diabetes. J. Clin. Invest. 108(7), 1001-1013 (2001).