The instant invention is directed to a process for synthesizing substituted prolines, in particular, optically pure substituted prolines, which comprises the steps of:
a) adding an unsubstituted or substituted proline alkali salt and an alkali halide to a solution of dialkylacylamidomalonate; and
b) adding &agr;, &bgr; unsaturated aldehyde to produce an adduct.
Peptide analog type-B CCK receptor ligands or pharmaceutically-acceptable salts thereof, which are useful for treating central nervous system disorders, substance abuse, gastrointestinal disorders, endocrine disorders, eating-related disorders and for the treatment of shock, respiratory and cardiocirculatory insufficiencies.
A tetrapeptide type-B CCK receptor ligand of the formula
A-B-C-D
or a pharmaceutically acceptable salt thereof, which is useful for treating central nervous system disorders, substance abuse, gastrointestinal disorders, endocrine disorders, eating-related disorders and treatment of shock, respiratory and cardiocirculatory insufficiencies.