| 摘要 |
<p>A process for producing racemic or optically active threo- or erythro-3-(3,4-dihydroxyphenyl)serine represented by the formula < IMG > ¢I!, which comprises phthaloylating the amine group of a racemic or optically active threo- or erythro-3-(3,4-dihydroxyphenyl)serine derivative represented by the general formula < IMG > ¢IV! (wherein R1 and R2 each represents a hydrogen atom or a methyl group, or R1 and R2 jointly form a methylene group, provided that R1 and R2 do not simultaneously represent hydrogen atoms) to yield a racemic or optically active threo- or erythro-N-phthaloyl-3-(3,4-dihydroxy-phenyl)serine derivative represented by the general formula, ¢III! < IMG > wherein R1 and R2 are as defined above; if necessary in the case in which the compound of formula ¢III! is in racemic form, subjecting the racemate to optical resolution through the reaction with one of the optically active amines to yield an optically active threo- or erythro-N-phthaloyl-3-(3,4-dihydroxyphenyl)serine derivative represented by the general formula ¢III!; treating the racemic or optically active threo- or erythro-N-phthaloyl-3-(3,4-dihydroxyphenyl)serine derivative represented by the above formula ¢III! with a Lewis acid to yield racemic or optically active threoor erythro-N-phthaloyl-3-(3,4-dihydroxyphenyl-serine represented by the formula, < IMG > ¢II!; // if necessary in the case in which the compound of formula ¢II! is in racemic form, subjecting the racemate to optical resolution through the reaction with one of the optically active amines to yield an optically active threo- or erythro-N-phthaloyl-3-(3,4-dihydroxypheny)serine represented by the above formula ¢II!, and removing the phthaloyl group from the racemic or optically active threo- or erythro-N-phthaloyl-3-(3,4-dihydroxyphenyl)-serine to yield the racemic or optically active threoor erythro-3-(3,4-dihydroxyphenyl)serine represented by the above formula ¢I!.</p> |
