Glutamic acid derivatives, processes and intermediates for their preparation and pharmaceutical formulations containing them

Claim 1

(1) A process for the preparation of a compound of formula (I): wherein R¹ is hydrogen, C 1-4 alkyl, acetyl or formyl; R² and R³ are the same or different and are hydrogen or C 1-4 alkyl; R⁴ is NR¹¹R¹²; R¹¹, R¹², R⁵ and R⁶ are the same or different and are hydrogen, C 1-4 alkyl or C 1-12 acyl; R⁷, R⁸, R⁹ and R¹⁰ are the same or different and are hydrogen, halo, C 1-4 haloalkyl, C 1-4 alkyl and C 1-4 alkoxy; and n is 2, 3, 4 or 5; m is o or an integer from 1 to 6; or a salt thereof, which comprises deacylating a compound of formula (II): wherein R¹ is hydrogen or C 1-4 alkyl; R², R³, R⁷, R⁸, R⁹ and R¹⁰ and n and m are as defined in herein; one of the groups R⁵, R⁶, R¹¹, R¹² being C 1-12 acyl, the other groups R⁵, R⁶, R¹¹, and R¹² being the same or different and are hydrogen or C 1-12 acyl, and optionally thereafter (i) in the case where, in the resulting compound of formula (I) R¹ is hydrogen, formylating the compound so as to prepare the corresponding compound of formula (I), wherein R¹ is formyl; and/or (ii) converting R², R³, R⁵, R⁶, R¹¹ and R¹² in the resulting compound of formula (I) into another R², R³, R⁵, R⁶, R¹¹ and R¹²; and optionally forming a salt.