DERIVES DE L'ACIDE 3-AMINO-2-HYDROXY BUTANOYLAMINOACETIQUE ET LEUR PROCEDE DE PREPARATION

LA PRESENTE INVENTION A POUR OBJET DES DERIVES DE L'ACIDE THREO-3-AMINO-2-HYDROXY BUTANOYLACETIQUE DE FORMULE:(CF DESSIN DANS BOPI)DANS LAQUELLE:R EST UN RADICAL NAPHTYLE OU:(CF DESSIN DANS BOPI)DANS LAQUELLE R ET R, INDEPENDAMMENT L'UN DE L'AUTRE, SONT DES ATOMES D'HYDROGENE OU DE FLUOR OU UN GROUPE HYDROXY, HYDROXY PROTEGE, ALKOXY INFERIEUR, ALKYLE INFERIEUR AYANT 2 A 4 ATOMES DE CARBONE OU UN RADICAL PHENYLE ETANT ENTENDU QUE LORSQUE L'UN DES RADICAUX R ET R EST UN ATOME D'HYDROGENE OU UN GROUPE HYDROXY, L'AUTRE N'EST PAS UN ATOME D'HYDROGENE, ET R EST UN RADICAL ALKYLE COMPORTANT 3 OU 4 ATOMES DE CARBONE OU 3-GUANIDINOPROPYLE.ELLE SE RAPPORTE A DES DERIVES DE L'ACIDE 3-AMINO-2-HYDROXY BUTANOYLAMINOACETIQUE ET LEUR PROCEDE DE PREPARATION. A process for producing threo-3-amino-2-hydroxybutanoylaminoacetic acids comprises the steps of allowing to react a starting compound represented by the general formula: (I) wherein R1 represents a naphthyl or a group of the formula: in which R6 and R7 represent individually hydrogen, halogen, amino or a protected amino, hydroxy or a protected hydroxy, a lower alkoxy or a lower alkyl and R2 represents a protected amino, with a starting compound represented by the general formula: (II) wherein R3 represents hydrogen or an ester residue, to obtain threo-3-protected amino-2-hydroxy-4-oxobutanoic acid or its ester represented by the general formula: (III) wherein R1, R2 and R3 have the same meanings as above, and then reducing the same into threo-3-protected amino-2-hydroxybutanoic acid or its ester represented by the general formula: (IV) wherein R1, R2 and R3 have the same meanings as above, and further converting the above compound into 3-amino-2-hydroxybutanoic acid represented by the general formula: (V) wherein R2' represents amino or a protected amino, thereafter condensing the same, in a conventional manner for forming a peptide coupling, with a compound represented by the general formula: (VI) wherein R4 represents an alkyl having 3-4 carbon atom or 3-guanidinopropyl, while previously protecting as required those groups not relevant to the reaction, and removing the protecting groups for the functional groups to produce threo-3-amino-2-hydroxybutanoylaminoacetic acids represented by the general formula: (VII) wherein R1 and R4 have the same meanings as above. This invention also provides the compounds represented by the general formula (III) as novel intermediates for the above aimed compounds and a process for pr