136912-19-1 Cyclo(GP-psi(CH2SO)-gfp) Cyclo(gly-pro-psi(CH2SO)-gly-phe-pro) Cyclo(glycyl-prolyl-psi(CH2SO)-glycyl-phenylalanyl-prolyl) L-Prolinamide, N-(mercaptoacetyl)-D-phenylalanyl-N-(2-(2-(mercaptomethyl)-1-pyrrolidinyl)-2-oxoethyl)-, cyclic (1-2)-sulfide, S-oxide, (S-(R*,R*))-