摘要:
Racemic cis-2-amino-1-cyclopentane- or -cyclohexane-1-carboxylic acid was reacted with (R)-alpha-methylbenzylamine to form homochiral amides 3, 4 and 8, 9. The ring closures of 3, 4 and 8, 9 with aryl imidates resulted in cyclopentane cis-fused and cyclohexane cis- and trans-fused dihydropyrimidin-4-one enantiomers with loss of the N-substituent. The absolute configurations were determined by hydrolysis of 5, 6 and 10-13 to the corresponding amino acids. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.