The present invention relates to an improved process for the preparation of N-[4-[(3-chloro-4-fluorophenyl)amino]-7-[[(3S)-tetrahydro-3-furanyl]oxy]-6-quinazolinyl]-4-(dimethyl amino)-(2E)-2-butenamide (2Z)-2-butenedioate (1:2) represented by the following structural formula: ##STR00001##

Disclosed herein is a use of an inorganic salt to form and regenerate a draw solute for forward osmosis, wherein the inorganic salt is selected from one or more of the group selected from sodium sulfate, calcium lactate, disodium phosphate, tetrasodium pyrophosphate, and hydrates thereof. Also disclosed herein is a method of forward osmosis using said inorganic salt.

The present invention relates to a novel process for preparation of boscalid anhydrate form I and boscalid anhydrate form II.

Disclosed in the present specification is a method capable of preparing N-[4-[(1R)-1-[[(R)-(1,1-dimethylethyl)sulfinyl]amino]ethyl]-2,6-difluorophenyl]-methanesulfonamide (INT028-2) with high optical purity, through the selection of Ellman-chiral auxiliaries and the re-crystallization and separation of optical isomers. According to the above method, high-purity N-[4-[(1R)-1-[[(R)-(1,1-dimethylethyl)sulfinyl]amino]ethyl]-2,6-difluorophenyl]-methanesulfonamide with excellent quality can be produced at room temperature by improving cryogenic process conditions necessary for realizing high optical purity, and thus the trimming due to the process failure rate can be remarkably reduced.

The present invention relates to a processes for the preparation of 2-{4-[(5,6-diphenyl pyrazin-2-yl)(isopropyl)amino]butoxy}-N-(methylsulfonyl)acetamide compound of formula-1 and novel polymorphs thereof.

The present invention generally relates to a process of preparing iosimenol and a process of preparing a crystal of iosimenol, as well as a crystal of iosimenol prepared by these processes.

A target bipyridine compound is synthesized with high purity and a high yield in a simple and safe manner in a short period of time. A method for synthesizing a di-tert-butyl-2,2-bipyridine compound is provided, and the method includes a step of reacting, in a reaction solvent, a tert-butylpyridine compound with a dispersion product obtained by dispersing an alkali metal in a dispersion solvent. A method for synthesizing a bipyridine compound having no substituents is also provided, and the method includes a step of reacting, in a reaction solvent, pyridine with a dispersion product obtained by dispersing an alkali metal in a dispersion solvent.

Provided is a purifying method for dabigatran etexilate free base, comprising subjecting a dabigatran etexilate free base crude product to water slurrying to obtain a crude product B; then conducting recrystallization on the crude product B with acetone and water to obtain a crude product C; and subsequently, purifying the crude product C with a mixed solvent of tetrahydrofuran and ethyl acetate, filtering and drying to obtain a dabigatran etexilate free base finished product. The purifying method of the present invention can effectively remove various impurities and is suitable for workshop production. Salts and water-soluble organic impurities are removed by purified water slurrying, impurities with a high polarity are removed by purifying with an acetone-water solution, and impurities with a low polarity are removed by purifying with a mixed solvent of tetrahydrofuran and ethyl acetate.

A method for precipitating as particles 2,6-diamino-3,5-dinitropyrazine-1-oxide (or ANPZO) present in an acid medium, which comprises adding the acid medium to an aqueous solution and which is characterized in that the aqueous solution comprises a nitrate salt. Further disclosed is a method for synthesizing ANPZO implementing this precipitation method. The synthesis method comprises converting 2,6-diaminopyrazine-1-oxide (or DAPO) into ANPZO by nitration in an acid medium, and then precipitating as particles the ANPZO by adding the acid medium to an aqueous solution, and is characterized in that the aqueous solution comprises a nitrate salt.

Provided is an industrially feasible method for separating tritiated water from contaminated water. The method for separating tritiated water from light water contaminated by the tritiated water, includes the steps of; adding heavy water to the contaminated water; converting the liquid mixture of the contaminated water and the heavy water into a mixture of the light water and a gas hydrate consisting essentially of the tritiated water and the heavy water as the crystal structure under a condition of converting into the gas hydrate of at least one of the heavy water and the tritiated water, and yet keeping most of the light water in liquid state; and separating the gas hydrate from the light water.