Access to Enantiomerically Pure cis- and trans- β-Phenylproline by HPLC Resolution
نویسندگان
چکیده
SHORTENED TITLE: HPLC resolution of cis-and trans-β-phenylproline ABSTRACT The preparation of all four stereoisomers of the proline analogue that bears a phenyl group attached to the β carbon either cis or trans to the carboxylic acid (cis-and trans-β-phenylproline, respectively) has been addressed. The methodology developed allows access to multigram quantities of the target amino acids in enantiomerically pure form and suitably protected for use in peptide synthesis. Racemic precursors of cis-β-phenylproline and trans-β-phenylproline were prepared from easily available starting materials and subjected to HPLC enantioseparation. Semi-preparative columns (250 mm × 20 mm) containing chiral stationary phases based on amylose (Chiralpak ® IA) or cellulose (Chiralpak ® IC) were used, respectively, for the resolution of the cis-and trans-β-phenylproline precursors.
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