p. 377 - 380
(2007/10/02)(2R,3S)-2-Dibenzylamino-3-methyl-pentanedioic acid di-tert-butyl ester
ethyl cis-3-methylpyroglutamate
2,2-diethyl 3-methyl-5-oxopyrrolidine-2,2-dicarboxylate
cis-3-methylpyroglutamic acid
(2S,3R)-2-Dibenzylamino-3-methyl-pentanedioic acid