Dongkook Pharmaceutical Co., Ltd.

Yonsung Fine Chemical Co., Ltd.

Won Hun Ham

Yong Hyun Kim

Kee Young Lee

Chang Young Oh

Jin Kyu Park

Han Won Lee

Sung Ki Seo

Kyung Seok Choi

Min Sung Park

Young Hun Jung

Yiu Suk Lee

Ki Young Lee

The present invention relates to a novel process for preparing sulfamoyl-substituted phenethylamine derivatives, specifically, 5-{2-[2-(2-alkoxy-phenoxy)ethylamino]-propyl}-2-methoxy-benzene sulfonamide of the formula (1).

Process for preparing sulfamoyl-substituted phenethylamine derivatives

The present invention relates to stereoselective synthetic method of oxazoline derivative. More particularly, it relates to a synthetic method of oxazoline derivative having the structure of formula I. ##STR1## wherein R represents phenyl, benzyl, methyl, ethyl, isopropyl, isobutyl, cyclohexyl or cyclohexylmethyl.

Stereoselective synthesis of oxazoline derivative

The present invention relates to a process for the preparation of an oxazoline compound which is easily chemically converted to a beta-amino-alpha-hydroxy acid or a gamma-amino-beta-hydroxy acid. The method comprises producing a compound of the following formula (4) using .alpha.-amino acid. The produced compound (4) is subjected to an intramolecular cyclization to produce an oxazoline compound of the following formula (3). The oxazoline compound (3) is oxidized at a vinyl group with RuCl.sub.3 or NaIO.sub.4 to produce an oxazoline compound of the following formula (1) which is easily chemically converted to a beta-amino-alpha-hydroxy acid. Alternatively, the oxazoline compound (3) may also be treated with 9-borabiclo[3.3.1]nonane such that a hydroxy group is introduced into the end of the vinyl group of the oxazoline compound(3). The introduced end hydroxy group is oxidized with RuCl.sub.3 or NaIO.sub.4 to produce an oxazoline compound of the following formula (2) which is easily chemically converted to a gamma-amino-hydroxy acid.

Process for the preparation of oxazoline compound

A preparation of 3-amino-1-hydroxypropane-1,1-diphosphonic acid includes the steps of: mixing N-alkoxycarbonyl-.beta.-alanine, phosphorous chloride and phosphorous acid in the ratio of 1:1:1.about.1:3:3 in a reaction solvent, xylene at 70.degree.-140.degree. C.; hydrolyzing; and obtaining 3-amino-1-hydroxypropane-1,1-diphosphonic acid as a product, thus decreasing the production of unidentified by-products and giving and low production cost by using xylene instead of chlorobenzene as a reaction solvent.

Preparation of 3-amino-1-hydroxypropane-1, 1-diphosphonic acid

Growing community of inventors

Seoul, South Korea

Won Hun Ham