Patent ID: 8603975

Claim:
A cyclic peptide compound of the following general formula (I): wherein R 1 is methyl; R 2 is hydrogen; R 3 is (1) —NR 8 R 9 , wherein R 8 and R 9 are independently hydrogen, lower alkyl, heterocyclic group or acyl, each of which may have one or more suitable substituent(s); or alternatively R 8 and R 9 , together with the nitrogen atom to which they are attached, represent an N-containing heterocyclic group which may have one or more suitable substituent(s); or (2) —OC(O)—NR 10 R 11 , wherein R 10 and R 11 are independently hydrogen, lower alkyl, cyclo (lower) alkyl, aryl or heterocyclic group, each of which may have one or more suitable substituent(s); or alternatively R 10 and R 11 , together with the nitrogen atom to which they are attached, represent an N-containing heterocyclic group, which may have one or more suitable substituent(s); R 4 is hydrogen; R 5 is methyl or ethyl; R 6 is hydrogen or lower alkyl which may have one or more suitable substituent(s); R 7 is hydrogen; and represents single bond or a double bond; or a salt thereof.