Cyclo(3-methyl-D-2-hydroxybutanoyl-D-isoleucyl-L-2-hydroxypropanoyl-L-isoleucyl-3-methyl-D-2-hydroxybutanoyl-D-isoleucyl-L-2-hydroxypropanoyl-L-isoleucyl-3-methyl-D-2-hydroxybutanoyl-D-isoleucyl-L-2-hydroxypropanoyl-L-isoleucyl-3-methyl-D-2-hydroxybutanoyl-D-isoleucyl-L-2-hydroxypropanoyl-L-isoleucyl)