Patent ID: 7297793

Claim:
A compound represented by the formula: or a pharmaceutically acceptable salt thereof, wherein R 1 represents a hydrogen, alkyl, or a side chain of an amino acid selected from the group consisting of leucine, norleucine, isoleucine, allo-isoleucine, alanine, tert-leucine, and valine; R 2 represents cycloalkyl or aralkyl; R 3 represents alkyl, cycloalkyl, or cycloalkylalkyl; R 4 represents heterocyclo, heteroaryl, or aryl; R 6 represents a hydrogen or alkyl; R 7 and R 8 each independently represent a hydrogen or alkyl; and R 10 and R 11 together with the nitrogen atom to which they are bonded represent heterocyclo, aralkylheteroaryl, aralkylheterocyclo, heteroaralkylheteroaryl or heteroaralkylheterocyclo; wherein heteroaryl, as used alone or in combination, is optionally substituted with one or more radicals selected from the group consisting of alkyl, alkoxy, hydroxy, alkylthio, alkylsulfinyl, alkylsulfonyl, halo, amino, nitro, cyano, haloalkyl, carboxy, alkoxycarbonyl, alkanoylamino, amido, amidino, N-alkylamidino, alkylamino, dialkylamino, N-alkylamido, N,N-dialkylamido, alkoxycarbonylamino, and alkylsulfonylamino; wherein cycloalkyl and aryl, as used alone or in combination, are optionally substituted with one or more radicals selected from the group consisting of alkyl, alkoxy, hydroxy, alkylthio, alkylsulfinyl, alkylsulfonyl, halo, amino, nitro, cyano, haloalkyl, carboxy, alkoxycarbonyl, alkanoylamino, amido, amidino, N-alkylamidino, alkylamino, dialkylamino, N-alkylamido, N,N-dialkylamido, and alkoxycarbonylamino; and wherein heterocyclo, as used alone or in combination, is optionally substituted with one or more radicals selected from the group consisting of alkyl, alkoxy, hydroxy, amidino, N-alkylamidino, alkoxycarbonylamino, and alkylsulfonylamino.