This invention provides for a compound of formula (I), or a pharmaceutically acceptable salt thereof, wherein R.sup.A, R.sup.B, R.sub.2 and R.sub.4 are defined herein. The compounds of formula (I) and pharmaceutically acceptable salts thereof are cationic lipids useful in the delivery of biologically active agents to cells and tissues.

##STR00001##

This invention provides for a compound of formula (I), or a pharmaceutically acceptable salt thereof, wherein R.sup.A, R.sup.B, R.sub.2 and R.sub.4 are defined herein. The compounds of formula (I) and pharmaceutically acceptable salts thereof are cationic lipids useful in the delivery of biologically active agents to cells and tissues.

##STR00001##

The present invention provides a method for producing a high quality cationic surfactant, which is prevented from smelling and coloring, and has favorable storage stability.

The production method includes the following step 1, step 2, step 3, and step 4: step 1: a step of obtaining an alkanolamine ester by reacting an alkanolamine with a fatty acid or a fatty acid alkyl ester without using hypophosphoric acid or a salt thereof; step 2: a step of obtaining a cationic surfactant by quaternizing the alkanolamine ester obtained in the step 1 with a dialkyl sulfate; step 3: a step of performing an oxidation treatment of the cationic surfactant obtained in the step 2; and step 4: a step of performing a reduction treatment of the cationic surfactant subjected to the oxidation treatment obtained in the step 3.

The present invention provides a method for producing a high quality cationic surfactant, which is prevented from smelling and coloring, and has favorable storage stability.

The production method includes the following step 1, step 2, step 3, and step 4: step 1: a step of obtaining an alkanolamine ester by reacting an alkanolamine with a fatty acid or a fatty acid alkyl ester without using hypophosphoric acid or a salt thereof; step 2: a step of obtaining a cationic surfactant by quaternizing the alkanolamine ester obtained in the step 1 with a dialkyl sulfate; step 3: a step of performing an oxidation treatment of the cationic surfactant obtained in the step 2; and step 4: a step of performing a reduction treatment of the cationic surfactant subjected to the oxidation treatment obtained in the step 3.

The invention concerns new quaternary ammonium compounds with surfactant properties and improved biodegradability.

##STR00001##

Compounds represented by formulae I, II, III, and IV including pro-drugs for treprostinil and prostacyclin analogs. Uses include treatment of pulmonary hypertension (PH) or pulmonary arterial hypertension (PAH). The structures of the compounds can be adapted to the particular application for a suitable treatment dosage. Transdermal applications can be used.

Compounds represented by formulae I, II, III, and IV including pro-drugs for treprostinil and prostacyclin analogs. Uses include treatment of pulmonary hypertension (PH) or pulmonary arterial hypertension (PAH). The structures of the compounds can be adapted to the particular application for a suitable treatment dosage. Transdermal applications can be used.

The invention provides a lipid of Formula (I) and nanoparticle compositions containing the same. Nanoparticle compositions including therapeutic and/or prophylactics such as RNA are useful in the delivery of therapeutic and/or prophylactics to mammalian cells or organs to, for example, regulate polypeptide, protein, or gene expression.

##STR00001##

The disclosure provides ionizable amine lipids and salts thereof (e.g., pharmaceutically acceptable salts thereof) useful for the delivery of biologically active agents, for example delivering biologically active agents to cells to prepare engineered cells. The ionizable amine lipids disclosed herein are useful as ionizable lipids in the formulation of lipid nanoparticle-based compositions.

Compounds represented by formulae I, II, III, and IV including pro-drugs for treprostinil and prostacyclin analogs. Uses include treatment of pulmonary hypertension (PH) or pulmonary arterial hypertension (PAH). The structures of the compounds can be adapted to the particular application for a suitable treatment dosage. Transdermal applications can be used.