Linaclotide Dimer Impurity 44

(2S,2'S) -2,2'- (((3aS,6S,9R,12R,15S,18S,21R,26R,29S,32S,35R,38R,41S,43aS,49S,52R,57R,60S,65S,71R,78S,84R,93R,98R) -93,98-diamino-6,41-bis (2-amino-2-oxoethyl) -18,29-bis (2-carboxyethyl) -15,32-bis (4-hydroxybenzyl) -65,78-bis ((R) -1-hydroxyethyl) -49,60-dimethyl-4,5,8,11,14,19,20,27,28,33,36,39,42,43,50,59,63,66,69,76,79,82,94,97-tetracosaoxohexapentacontahydro-1H,25H-21,9:26,38-bis (epiminopropanodithiomethano) -12,57:35,52-bis (methanodithioethanoiminoethanoiminoethanoiminomethano) dipyrrolo[1,2-i:2',1'-y1][1,2,30,31]tetrathia[5,8,9,14,17,20,23,24,37,38,41,44,47,52,53,56]hexadecaazacyclooctapentacontine-71,84-dicarbonyl) bis (azanediyl) ) bis (3- (4-hydroxyphenyl) propanoic acid)