The present disclosure is directed synthetic methods for the preparation of 4-valyloxybutyric acid. The synthetic methods described herein employ a diverse array of protecting group strategies and reaction conditions. Additionally, the present disclosure is directed to compounds useful as synthetic intermediates in the preparation of 4-valyloxybutyric acid.

Provided are a method for producing a peptide compound including a step of using a condensed polycyclic aromatic hydrocarbon compound represented by Formula (1); a protective group-forming reagent including the compound; and the compound. In Formula (1), a ring A represents a condensed polycyclic aromatic hydrocarbon ring, Y.sup.A's each independently represent —OH, —NHR, —SH, or —X.sup.0, where X.sup.0 represents Cl, Br, or I, R.sup.A and R.sup.C each independently represent an aliphatic hydrocarbon group or an organic group having an aliphatic hydrocarbon group, R.sup.Bs' each independently represent a monovalent aliphatic hydrocarbon group, a (1+c)-valent aromatic group, or a (1+c)-valent heteroaromatic group, where, in a case where both a and c is 0, R.sup.B is a monovalent aliphatic hydrocarbon group, and the number of carbon atoms in at least one aliphatic hydrocarbon group is 12 or more.

##STR00001##

Provided are a method for producing a peptide compound including a step of using a condensed polycyclic aromatic hydrocarbon compound represented by Formula (1); a protective group-forming reagent including the compound; and the compound. In Formula (1), a ring A represents a condensed polycyclic aromatic hydrocarbon ring, Y.sup.A's each independently represent —OH, —NHR, —SH, or —X.sup.0, where X.sup.0 represents Cl, Br, or I, R.sup.A and R.sup.C each independently represent an aliphatic hydrocarbon group or an organic group having an aliphatic hydrocarbon group, R.sup.Bs' each independently represent a monovalent aliphatic hydrocarbon group, a (1+c)-valent aromatic group, or a (1+c)-valent heteroaromatic group, where, in a case where both a and c is 0, R.sup.B is a monovalent aliphatic hydrocarbon group, and the number of carbon atoms in at least one aliphatic hydrocarbon group is 12 or more.

##STR00001##

The present disclosure is directed synthetic methods for the preparation of 4-valyloxybutyric acid. The synthetic methods described herein employ a diverse array of protecting group strategies and reaction conditions. Additionally, the present disclosure is directed to compounds useful as synthetic intermediates in the preparation of 4-valyloxybutyric acid.

The present disclosure is directed synthetic methods for the preparation of 4-valyloxybutyric acid. The synthetic methods described herein employ a diverse array of protecting group strategies and reaction conditions. Additionally, the present disclosure is directed to compounds useful as synthetic intermediates in the preparation of 4-valyloxybutyric acid.

Provided herein are novel solid forms of each of four compounds: (1) heptadecan-9-yl 8-((2-hydroxyethyl)amino)octanoate (“Compound 1”), (2) heptadecan-9-yl 8-((2-hydroxyethyl)(6-oxo-6-(undecyloxy)hexyl)amino)octanoate (“Compound 2”), (3) heptadecan-9-yl 8-((2-hydroxyethyl)(8-(nonyloxy)-8-oxooctyl)amino)octanoate (“Compound 3”), and (6Z,9Z,28Z,31Z)-heptatriaconta-6,9,28,31-tetraen-19-yl 4-(dimethylamino)butanoate (“MC3”), and related compositions and methods.

Provided herein are novel solid forms of each of four compounds: (1) heptadecan-9-yl 8-((2-hydroxyethyl)amino)octanoate (“Compound 1”), (2) heptadecan-9-yl 8-((2-hydroxyethyl)(6-oxo-6-(undecyloxy)hexyl)amino)octanoate (“Compound 2”), (3) heptadecan-9-yl 8-((2-hydroxyethyl)(8-(nonyloxy)-8-oxooctyl)amino)octanoate (“Compound 3”), and (6Z,9Z,28Z,31Z)-heptatriaconta-6,9,28,31-tetraen-19-yl 4-(dimethylamino)butanoate (“MC3”), and related compositions and methods.

The present invention provides a method for synthesizing a carboxy-containing anthraquinone derivative, including the following steps: S1, mixing a terminal carboxy-containing dibasic acid with thionyl chloride, and adding toluene as a reaction solvent, followed by adding a catalyst and heating to a predetermined temperature for a reaction; S2, after the reaction is completed, removing the reaction solvent and the thionyl chloride, followed by adding toluene for distillation, to obtain a reactant; S3, mixing the reactant with aminoanthraquinone, adding toluene as a reaction solvent, followed by heating to reflux for a reaction; and S4, after the reaction is completed, removing the reaction solvent, adding a potassium carbonate solution to the residue, filtering it to remove a solid, adjusting the filtrate to a predetermined pH value to precipitate a solid, followed by filtering out, washing, and drying the precipitated solid, to obtain the carboxy-containing anthraquinone derivative.

The present invention provides a method for synthesizing a carboxy-containing anthraquinone derivative, including the following steps: S1, mixing a terminal carboxy-containing dibasic acid with thionyl chloride, and adding toluene as a reaction solvent, followed by adding a catalyst and heating to a predetermined temperature for a reaction; S2, after the reaction is completed, removing the reaction solvent and the thionyl chloride, followed by adding toluene for distillation, to obtain a reactant; S3, mixing the reactant with aminoanthraquinone, adding toluene as a reaction solvent, followed by heating to reflux for a reaction; and S4, after the reaction is completed, removing the reaction solvent, adding a potassium carbonate solution to the residue, filtering it to remove a solid, adjusting the filtrate to a predetermined pH value to precipitate a solid, followed by filtering out, washing, and drying the precipitated solid, to obtain the carboxy-containing anthraquinone derivative.

A magnesium citrate glycinate co-salt has a formula of Mg.sub.2C.sub.8H.sub.9NO.sub.9—XH.sub.2O and a suggested structure of: ##STR00001## The magnesium citrate glycinate co-salt has an apparent density of 1740 kg/m.sup.3 and is compressible in a range of compression pressures from approximately 50 MPa to approximately 150 MPa. The magnesium citrate glycinate co-salt is formed by combining citric acid and glycine in a 1:1 molar ratio to form an aqueous reaction mixture and neutralizing the aqueous reaction mixture with a magnesium source having a magnesium:ligand ratio of 1:1.