Process for preparing alpha-methyl-beta-(3,4-dihydroxyphenyl)-alanine
Abstract
Abstract 1-(X-CH2-),3-(R1-O-),4-(R2-O-)BENZENE WHEREIN EACH OF R1 AND R2 IS LOWER ALKYL, OR R1 AND R2 ARE COMBINED TOGETHER TO FORM A METHYLENE RADICAL AND X IS HALOGEN, TO PRODUCE A COMPOUND OF THE FORMULA: 1-(R-OOC-C(-CH3)(-CN)-CH2-),3-(R1-O-),4-(R2-O-)BENZENE A LOWER ALKYL ESTER OF A-ISOCYANO-PROPIONIC ACID IS CONDENSED WITH A COMPOUND OF THE FORMULA: WHEREIN R IS LOWER ALKYL, AND R1 AND R2 ARE AS DEFINED ABOVE. A-METHYL-B-(3,4-DIHYDROXYPHENYL)-ALANINE IS OBTAINED BY HYDROLYZING THE COMPOUND (II) WITH CONCENTRATED MINERAL ACID. ALTERNATIVELY, A-METHYL-B-(3,4-DIHYDROXYPHENYL)-ALAMINE MAY BE OBTAINED BY HYDROLYZING COMPOUND (II) WITH DILUTE MINERAL ACID TO PRODUCE THE CORRESPONDING A-METHYL-B-PHENYLALANINE ESTER, HYDROLYZING THE ALANINE ESTER WITH A ALKALI METAL HYDROXIDE TO PRODUCE THE CORRESPONDING A-METHYL-B-PHENYLALANINE, AND THEN HYDROLYZING SOME WITH CONCENTRATED MINERAL ACID.
Inventors
- 👤 M Suzuki
- 👤 K Okumura
- 👤 K Matsumoto
Bibliographic Details
Claims Analysis
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