| 摘要 |
The invention provides salts of formula (I) wherein X is a basic counterion selected from a group I or group II metal and a primary, secondary or tertia ry amine; n is 0, 1 or 2; and Rl, Rla, R2, R2a, R3, R3a, R4 and R4a are independently selected from H and C1-C6 alkyl, or R1 and R2 or R2 and R3 are taken together to form a C3-C7 cycloalkyl ring, which is optionally substituted with one or two substituents selected from C1-C6 alkyl, which ar e useful as intermediates in the preparation of cyclic and bicyclic amino acid s. Processes for the preparation of the final products and for the conversion o f the compounds of formula (.IOTA.) to amino acids are included.
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