Isopropyl unoprostone CAS NO.120373-24-2

Unoprostone isopropyl ester (Rescula) is the clinically approved, prodrug form of unoprostone, which is a free acid analog of prostaglandin F_2α (PGF_2α). Both latanoprost and Rescula have been approved for the treatment of ocular hypertension. Both analogs of PGF_2α are believed to act by increasing the rate of aqueous humor outflow through the uveoscleral pathway. Both drugs are believed to act as prodrugs, with endogenous esterases within the eye releasing the free acid active form of the drug. The typical does of Rescula (one drop of 0.12% solution) is nearly 100 times that of latanoprost. Rescula has very little activity on isolated DP or TP receptors, less than 0.0005% the activity of PGE₂ on EP₃ receptors, and about 3% of the activity of PGF_2α on FP receptors.

Unoprostone isopropyl ester, a novel prostaglandin derivative, was launched in Japan as eye drops for the treatment of glaucoma and ocular hypertension. In animal and human studies, a single drop of unoprostone isopropyl ester induced significant decrease in intraocular pressure without systemic effects, myosis or mydriasis. Unlike prostaglandin analogs such as PGF_2α, unoprostone isopropyl ester does not cause irritation in outer segment of the eye or significant changes in aqueous protein concentration and corneal endothelial permeability. Unoprostone isopropyl ester is suggested to act by increasing uveoscleral outflow or by decreasing episcleral venous pressure, resulting in ocular hypotension