The present disclosure provides treprostinil derivatives that can act as prodrugs of treprostinil. The treprostinil derivatives can be used to treat any conditions responsive to treatment with treprostinil, including pulmonary hypertension, such as pulmonary arterial hypertension.

The present invention relates to a process for the preparation of aqueous solutions of [1-.sup.13C]-hyperpolarized carboxylate containing molecules of diagnostic interest that comprises parahydrogenating with molecular parahydrogen unsaturated alkenyl or alkynyl esters of the concerned .sup.13C-carboxylate molecules.

The present invention relates to a process for the preparation of aqueous solutions of [1-.sup.13C]-hyperpolarized carboxylate containing molecules of diagnostic interest that comprises parahydrogenating with molecular parahydrogen unsaturated alkenyl or alkynyl esters of the concerned .sup.13C-carboxylate molecules.

An object of the present invention is to provide a chemical liquid purification method which makes it possible to obtain a chemical liquid having excellent defect inhibition performance. Another object of the present invention is to provide a chemical liquid. The chemical liquid purification method according to an embodiment of the present invention is a chemical liquid purification method including obtaining a chemical liquid by purifying a substance to be purified containing an organic solvent, in which a content of the stabilizer in the substance to be purified with respect to the total mass of the substance to be purified is equal to or greater than 0.1 mass ppm and less than 100 mass ppm.

The invention pertains to a process for preparing methyl lactate including the steps of: bringing an aqueous liquid comprising lactic acid, methanol, and at least 5 wt. % of a dissolved chloride salt selected from magnesium chloride, calcium chloride, and zinc chloride to reaction conditions, thereby obtaining methyl lactate, wherein an extractant is provided to the reaction mixture before, during, and/or after formation of methyl lactate; subjecting the reaction mixture to a liquid-liquid separation step wherein an organic phase comprising methyl lactate and extractant is separated from an aqueous phase comprising dissolved chloride salt. The extractant preferably includes one or more compounds selected from C5+ ketones and C3-C10 ethers, in particular C5-C8 ketones, more in particular methyl isobutyl ketone. It has been found that the process according to the invention makes it possible to manufacture methyl lactate efficiently and in high yield.

The invention pertains to a process for preparing methyl lactate including the steps of: bringing an aqueous liquid comprising lactic acid, methanol, and at least 5 wt. % of a dissolved chloride salt selected from magnesium chloride, calcium chloride, and zinc chloride to reaction conditions, thereby obtaining methyl lactate, wherein an extractant is provided to the reaction mixture before, during, and/or after formation of methyl lactate; subjecting the reaction mixture to a liquid-liquid separation step wherein an organic phase comprising methyl lactate and extractant is separated from an aqueous phase comprising dissolved chloride salt. The extractant preferably includes one or more compounds selected from C5+ ketones and C3-C10 ethers, in particular C5-C8 ketones, more in particular methyl isobutyl ketone. It has been found that the process according to the invention makes it possible to manufacture methyl lactate efficiently and in high yield.

The invention describes pharmaceutical compounds and compositions comprised of prodrug ligands attached to GHB (CNS drugs) in a manner that substantially decreases or deters the potential for GHB abuse, illicit and illegal use, and overdose. These compounds and compositions may provide substantially higher bioavailability, substantially higher half-life, substantially higher chemical and biological stability, and easier shipping and distribution requirements. These GHB prodrug compounds may alter both the physical and chemical properties and thus may not be suitable for illicit use as a date-rape drug (i.e., they may not dissolve instantly in water based drinks, may have different color once in solution, and/or may have a taste and odor once in solution etc.). When delivered at the proper dosage, the pharmaceutical composition provides therapeutic activity similar to that of the parent active agent GHB.

The present disclosure provides treprostinil derivatives that can act as prodrugs of treprostinil. The treprostinil derivatives can be used to treat any conditions responsive to treatment with treprostinil, including pulmonary hypertension, such as pulmonary arterial hypertension.

The present disclosure provides treprostinil derivatives that can act as prodrugs of treprostinil. The treprostinil derivatives can be used to treat any conditions responsive to treatment with treprostinil, including pulmonary hypertension, such as pulmonary arterial hypertension.

A method of preparing an ester by reacting a carboxylic acid with a (C.sub.1-C.sub.36)alcohol in the presence of a catalyst that is suitable for preparing carboxylic acid esters of monomeric carboxylic acids in high yield. The method reduces by-products of the reaction, in particular esters of dimeric, trimeric and/or oligomeric carboxylic acids. The method requires a minimal excess of alcohol and does not require removal of water and/or carboxylic acid ester from the reaction mixture. The method is particularly suitable for the reaction of hydroxyalkylcarboxylic acids and fatty alcohols.