Thyropropic Acid (also known as Triopron) is a hydrocinnamic acid derivative and naturally occurring thyroid analog with antigoitrogenic and anticholesteremic activity. Thyropropic Acid acts as potent antagonist of thyroid hormone receptors and may be useful in the therapy of resistance to thyroid hormone and corticosteroid-induced skin atrophy. In preclinical models, Thyropropic Acid reduced serum cholesterol 27% and liver incorporation of acetate into cholesterol 37% but did not affect liver cholesterol levels.