Disclosed are compounds of Formula (I) or pharmaceutically acceptable salts thereof, wherein W, X, Y, Z, R
1
, R
2
, R
3
and R
4
are described in this application, and methods of using said compounds in the treatment of cancer.
An amino acid derivative having an angiotensin I-converting enzyme inhibitor activity, a vasopressin antagonism and an atrial natriuretic peptide hydrolase inhibitor activity, and represented by general formula (I) wherein R¹ represents hydrogen or acyl; R² represents hydrogen, lower alkyl, cycloalkyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted arylalkyl or optionally substituted heteroarylalkyl; m and n represent each independently an integer of 0.1 or 2; and J represents a cyclic group having an angiotensin I-converting enzyme inhibitor activity.