Patent ID: 7872097

Claim:
A cyclic peptide compound of the following general formula (I): wherein X is in which R 1 is hydrogen or lower alkyl; R 2 is hydrogen, aryl or lower alkyl which is optionally substituted by a suitable substituent selected from the group consisting of: hydroxy, cyclo(lower)alkyl, lower alkoxy, aryl, aryl(lower)alkoxy, optionally substituted carbamoyloxy, and optionally substituted amino; and is N-containing heterocyclic group; Y is in which R 3 is cyclo(lower)alkyl, aryl, optionally substituted heterocyclic group, or lower alkyl which is optionally substituted by a suitable substituent selected from the group consisting of: hydroxy, cyclo(lower)alkyl, lower alkoxy, aryl, aryl(lower)alkoxy, lower alkoxy(lower)alkoxy, optionally substituted amino, and —OC(O)NR 6 R 7 (wherein R 6 and R 7 are each independently hydrogen or lower alkyl, or alternatively R 6 and R 7 , together with the nitrogen atom to which they are attached, represent N-containing heterocyclic group which is optionally substituted by a lower alkyl); and R 4 and R 5 are each independently hydrogen or lower alkyl; and --- represents single bond or double bond; or a salt thereof, provided that, when R 2 is hydrogen, R 3 is cyclo(lower)alkyl, aryl, optionally substituted heterocyclic group, lower alkoxymethyl, aryl(lower)alkyl, t-butyl, sec-butyl, cyclo(lower)alkyl(lower)alkyl, or ethyl substituted by a suitable substituent selected from the group consisting of hydroxy, lower alkoxy, aryl(lower)alkoxy, lower alkoxy(lower)alkoxy, optionally substituted amino and —OC(O)NR 6 R 7 (wherein R 6 and R 7 are each as defined above).