| 摘要 |
Process for the preparation of substituted thiazolines of the formula (I) in which Ar is a phenyl, naphthyl, thienyl, pyridyl or quinolinyl radical which can optionally be substituted by one or more substituents from the group consisting of halogen, OH, benzyloxy, C<SUB>1</SUB>-C<SUB>4</SUB>-alkyl, C<SUB>1</SUB>-C<SUB>4</SUB>-alkoxy, COOR<SUB>1 </SUB>where R<SUB>1 </SUB>is H or C<SUB>1</SUB>-C<SUB>4</SUB>-alkyl, by coupling of (S)-alpha-methylcysteine hydrochloride of the formula (II) with a nitrile of the formula (III) <?in-line-formulae description="In-line Formulae" end="lead"?>Ar-CN <?in-line-formulae description="In-line Formulae" end="tail"?> in which Ar is as defined above, or a corresponding C<SUB>1</SUB>-C<SUB>4</SUB>-alkyl imidate, in which (S)-alpha-methylcysteine hydrochloride of the formula (II) is reacted in a suitable solvent with a nitrile of the formula (III) or a corresponding C<SUB>1</SUB>-C<SUB>4</SUB>-alkyl imidate in the presence of a tertiary base at a pH of 6.5 to 10 at 50 ° C. up to the reflux temperature to give the corresponding thiazoline of the formula (I), and processes for the preparation of (S)-alpha-methylcysteine hydrochloride and its use for the preparation of thiazolines of the formula (I).
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