[(4R,7S,13S,16R)-16-(acetylamino)-4-carbamoyl-13-{3-[(diaminomethylidene)amino]propyl}-3,3,14-trimethyl-6,9,12,15-tetraoxo-1,2-dithia-5,8,11,14-tetraazacycloheptadecan-7-yl]acetic acid