The invention provides salts of formula (I)
1
wherein X is a basic counterion selected from a group I or group II metal and a primary, secondary or tertiary amine;
n is 0, 1 or 2; and
R
1
, R
1a
, R
2
, R
2a
, R
3
, R
3a
, R
4
and R
4a
are independently selected from H and C
1
-C
6
alkyl, or
R
1
and R
2
or R
2
and R
3
are taken together to form a C
3
-C
7
cycloalkyl ring, which is optionally substituted with one or two substituents selected from C
1
-C
6
alkyl, which are useful as intermediates in the preparation of cyclic and bicyclic amino acids. Processes for the preparation of the final products and for the conversion of the compounds of formula (I) to amino acids are included.
本发明提供了式(I)的盐,其中X是从I组或II组
金属和一次、二次或三次胺组成的基本阳离子;n为0、1或2;而R1、R1a、R2、R2a、R3、R3a、R4和R4a独立地选择自H和C1-C6烷基,或者R1和R2或R2和R3结合形成一个C3-C7
环烷基环,其可选地被一个或两个从C1-C6烷基中选择的取代基取代,这些盐在制备环状和双环
氨基酸的
中间体时有用。本发明还包括制备最终产物以及将式(I)化合物转化为
氨基酸的方法。