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.

In methods for preparing an alkyl carboxylic acid ester according to embodiments of the present invention, a first reaction product is produced by reaction of a carboxylic acid stream and a first alcohol stream in a preliminary reactor. A second reaction product is produced by at least partially removing alcohol and water from the first reaction product. The second reaction product is esterified by reaction with a second alcohol stream in a main reactor. An alkyl carboxylic acid ester is recovered from the main reactor.

In methods for preparing an alkyl carboxylic acid ester according to embodiments of the present invention, a first reaction product is produced by reaction of a carboxylic acid stream and a first alcohol stream in a preliminary reactor. A second reaction product is produced by at least partially removing alcohol and water from the first reaction product. The second reaction product is esterified by reaction with a second alcohol stream in a main reactor. An alkyl carboxylic acid ester is recovered from the main reactor.

A process is provided for the preparation of value added chemicals such as ethyl levulinate from a glucose or other sugars, catalyzed by a mixture of a Lewis acid catalyst and a Bronsted acid catalyst.

A process is provided for the preparation of value added chemicals such as ethyl levulinate from a glucose or other sugars, catalyzed by a mixture of a Lewis acid catalyst and a Bronsted acid catalyst.

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 synthesis method of alpha-hydroxycarboxylic acid ester is provided. In the method, an alpha-hydroxycarboxylic acid and an alcohol are taken as raw materials, one or more of boric acid, metaboric acid, pyroboric acid, and boric anhydride is taken as a catalyst, and one of cyclohexane, toluene, benzene, and alcohols is taken as a water-carrying agent. A reaction temperature is kept in range of 100-160° C., produced water is separated by an oil-water separator, and the alpha-hydroxycarboxylic acid ester is synthesized directly. After an esterification reaction, the water-carrying agent and unreacted alcohol are distilled by vacuum fractionation to obtain a crude product, and refined alpha-hydroxycarboxylic acid ester is obtained by performing neutralization, water washing, and vacuum rectification on the crude product. The alpha-hydroxycarboxylic acid ester prepared by the method has high purity and light color, and can be used as green solvent, surfactant, chiral resolution agent and plasticizer.

A synthesis method of alpha-hydroxycarboxylic acid ester is provided. In the method, an alpha-hydroxycarboxylic acid and an alcohol are taken as raw materials, one or more of boric acid, metaboric acid, pyroboric acid, and boric anhydride is taken as a catalyst, and one of cyclohexane, toluene, benzene, and alcohols is taken as a water-carrying agent. A reaction temperature is kept in range of 100-160° C., produced water is separated by an oil-water separator, and the alpha-hydroxycarboxylic acid ester is synthesized directly. After an esterification reaction, the water-carrying agent and unreacted alcohol are distilled by vacuum fractionation to obtain a crude product, and refined alpha-hydroxycarboxylic acid ester is obtained by performing neutralization, water washing, and vacuum rectification on the crude product. The alpha-hydroxycarboxylic acid ester prepared by the method has high purity and light color, and can be used as green solvent, surfactant, chiral resolution agent and plasticizer.

The present invention describes storage-stable glycerol (meth)acrylate carboxylic esters and a method for preparing these esters.