There is disclosed a process for the separation of long chain amino acid and long chain dibasic acid, comprising: (1) mixing the mixed amide derivatives with an aqueous solution of ammonia or ammonium hydroxide in the presence or absence of solvent or catalyst; (2) subjecting the solution or suspension of step (1) to an hydrolysis reaction; and (3) recovering excess ammonia and solvent in the presence of solvent in step (1) by evaporation to provide a mixture of long chain amino acid and alkylamine or ammonium salts of long chain dibasic acid and alkanoic acid.

The present invention relates to a preparation method for a sarcosinate including: step 1, reacting a solution of glyoxylic acid or a glyoxylate with an amine solution to prepare a Schiff base solution; step 2, subjecting the prepared Schiff base solution to a hydrogenation reaction under the condition of a catalyst; and step 3, adjusting a pH value of a solution obtained after the hydrogenation reaction to be alkaline to obtain the sarcosinate. Wherein the pH value of the solution obtained after the hydrogenation reaction in the step 3 is adjusted to be acidic to obtain sarcosine. Wherein a sarcosinate solution obtained in the step 3 is reacted with cyanamide to prepare a sarcosine derivative. A novel preparation method for sarcosine and derivatives thereof in the present invention solves the problem of using highly toxic chemicals as raw materials in the existing production process of sarcosine or sarcosine derivatives such as creatine, while the new process is simpler and more efficient, has lower production cost, and is of great significance.

The present invention relates to a preparation method for a sarcosinate including: step 1, reacting a solution of glyoxylic acid or a glyoxylate with an amine solution to prepare a Schiff base solution; step 2, subjecting the prepared Schiff base solution to a hydrogenation reaction under the condition of a catalyst; and step 3, adjusting a pH value of a solution obtained after the hydrogenation reaction to be alkaline to obtain the sarcosinate. Wherein the pH value of the solution obtained after the hydrogenation reaction in the step 3 is adjusted to be acidic to obtain sarcosine. Wherein a sarcosinate solution obtained in the step 3 is reacted with cyanamide to prepare a sarcosine derivative. A novel preparation method for sarcosine and derivatives thereof in the present invention solves the problem of using highly toxic chemicals as raw materials in the existing production process of sarcosine or sarcosine derivatives such as creatine, while the new process is simpler and more efficient, has lower production cost, and is of great significance.

The present invention relates to trisodium diethylenetriamine pentaacetic acid (DTPA) prodrugs, such as, for example, DTPA di-ethyl esters. The invention further relates to compositions comprising DTPA prodrugs and methods of using the same.

There is disclosed a process for the separation of long chain amino acid and long chain dibasic acid, comprising: (1) recovering alkylamine by distilling or by extracting with an extractant solvent; (2) adding an acid an extractant solvent to the aqueous solution of step (1) to form an acidic salt of long chain amino acid to extract long chain dibasic acid; (3) separating the mixture of step (2) into an aqueous phase and an extractant phase; (4) neutralizing the aqueous phase of step (3) with an alkali hydroxide or ammonium hydroxide to obtain a crystalline solid of long chain amino acid; (5) cooling the extractant phase of step (3) to crystallize the long chain dibasic acid and recovering the dibasic acid by solid-liquid separation; and (6) recovering the extractant solvent of step (5) and isolating the alkanoic acid by distillation.

There is disclosed a process for the separation of long chain amino acid and long chain dibasic acid, comprising: (1) adding water and an extractant solvent to the aqueous suspension of an acid hydrolysis of the mixed amide derivatives to yield an aqueous solution and an extractant phase; (2) separating the mixture of step (1) into an aqueous phase containing the acid salt of long chain amino acid and alkylamine and an extractant phase containing long chain dibasic acid, short chain alkanoic acid, and impurities; (3) neutralizing the aqueous phase of step (2) with a basic agent to obtain a crystalline suspension of the long chain amino acid; (4) recovering the long chain amino acid by solid-liquid separation to yield an aqueous mother liquor; and (5) in the extractant phase of step (2), separating the long chain dibasic acid, short chain alkanoic acid, and impurities.

The present invention relates to a process for the preparation of Levothyroxine and salts thereof. The process described in the present invention provides increase in the yields and purity comprising the use of sodium iodide and sodium hypochlorite as iodinating agent.

The invention is directed to compounds of general formula (I), and pharmaceutical compositions containing such compounds. The compounds and compositions have valuable pharmaceutical properties. In particular, they may be used for the treatment of cancer. Novel intermediates and novel methods of preparation are also disclosed.

##STR00001##

A method for producing a cationic lipid, wherein a cationic lipid represented by formula (1) is mixed with a tetraalkylammonium salt having X.sup. in an organic solvent, and a filtrate obtained by separating a tetraalkylammonium iodide deposited by filtration is concentrated to deposit a tetraalkylammonium iodide, thereby obtaining a cationic lipid represented by formula (2): ##STR00001##
wherein R.sup.1 to R.sup.5 and X.sup. are as defined herein.

The present invention relates to a process to crystallize a chelating agent containing a step of adding seeds to a saturated or supersaturated aqueous solution or dispersion of the chelating agent and a subsequent step of milling the dispersion, wherein the step of milling the dispersion is performed using equipment operating at at least 1,000 rpm, and to products obtainable by such process.