111924-44-8 Argiotoxin 673 Butanediamide, N1-(15,20-diamino-20-imino-4,9-dimethyl-14-oxo-4,9,13,19-tetraazaeicos-1-yl)-2-(((2,4-dihydroxyphenyl)acetyl)amino)-, (S-(R*,R*))-