# US 4,391,986 A · Process for producing threo-3-amino-2-hydroxybutanoyl-aminoacetic acids, as well as novel intermediates therefor and process for producing them

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- Number: US 4,391,986 A
- Document ID: US4391986A
- Status: Granted
- Kind: A
- Application number: 06/211,035
- Filed: 1980-11-28
- Granted: 1983-07-05
- Earliest claimed: 1978-11-25
- Assignees: Nippon Kayaku Kabushiki Kaisha
- Inventors: Hamao Umezawa; Takaaki Aoyagi; Tadashi Shirai; Rinzo Nishizawa; Masao Suzuki; Tetsushi Saino
- Web page: https://patentgrep.com/patent/US4391986A

## CPC

- C07C 237/20: the carbon skeleton containing six-membered aromatic rings
- A61K 38/00: Medicinal preparations containing peptides (peptides containing beta-lactam rings A61K31/00; cyclic dipeptides not having in their molecule any other peptide link than those which form their ring, e.g. piperazine-2,5-diones, A61K31/00; ergot alkaloids of the cyclic peptide type A61K31/48; containing macromolecular compounds having statistically distributed amino acid units A61K31/74; medicinal preparations containing antigens or antibodies A61K39/00; medicinal preparations characterised by the non-active ingredients, e.g. peptides as drug carriers, A61K47/00)
- Y02P 20/55: Design of synthesis routes, e.g. reducing the use of auxiliary or protecting groups
- C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS
- A61K: PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES (devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms A61J3/00; chemical aspects of, or use of materials for deodorisation of air, for disinfection or sterilisation, or for bandages, dressings, absorbent pads or surgical articles A61L; soap compositions C11D)
- Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS

## Abstract

Threo-3-protected amino-2-hydroxy-4-oxobutanoic acid or its esters represented by the formula: ##STR1## wherein R.sub.1 represents naphthyl or a group of the formula ##STR2## in which R.sub.6 and R.sub.7 represent individually hydrogen, halogen, amino, an amino protected with acyl, lower alkyloxycarbonyl or carbamoyl, hydroxy or protected with acyl, lower alkyloxycarbonyl or carbamoyl, lower alkoxy, lower alkyl or phenyl group; R.sub.2 represents an amine protected with acyl, lower alkyloxycarbonyl or carbamoyl; and R.sub.3 represents hydrogen, lower alkyl having 1 to 6 carbon atoms or benzyl.

## Claims

### Claim 1

Threo-3-protected amino-2-hydroxy-4-oxobutanoic acid or its esters represented by the formula: ##STR118## wherein R.sub.1 represents naphthyl or a group of the formula ##STR119## in which R.sub.6 and R.sub.7 represent individually hydrogen, halogen, amino or an amino protected with acyl, lower alkyloxycarbonyl or carbamoyl, hydroxy or hydroxy protected with acyl, lower alkyloxycarbonyl or carbamoyl, lower alkoxy, lower alkyl or phenyl group; R.sub.2 represents an amino protected with acyl, lower alkyloxycarbonyl or carbamoyl; and R.sub.3 represents hydrogen, lower alkyl having 1 to 6 carbon atoms, or benzyl.

### Claim 2 (depends on 1)

A compound according to claim 1, wherein
R.sub.1 is phenyl and
R.sub.3 is hydrogen.

### Claim 3 (depends on 1)

A compound according to claim 1, wherein
R.sub.1 is hydroxyphenyl and
R.sub.3 is hydrogen.