The tetraamine chelator outperforms HYNIC in a new technetium-99m-labelled somatostatin receptor 2 antagonist

EJNMMI Research

Table 1 Analytical data of the purified chelator-peptide conjugates

Compound	Sequence	Molecular weight (g/mol)	m/z (calc.)	MS (ESI):(m/z)	Purity (%)
SS-03	DOTA-(4-Cl)-Phe-Cyclo(D-Cys-Tyr-D-Trp-Lys-Thr-Cys)-D-Tyr-NH₂	1531.15	1529.59	767.2 [M+2H]⁺⁺	99.5
SS-03		1531.15	1529.59	1531.8 [M+H]⁺	99.5
SS-04	N4-(4-Cl)-Phe-Cyclo(D-Cys-Tyr-D-Trp-Lys-Thr-Cys)-D-Tyr-NH₂	1331.01	1329.56	667.7 [M+2H]⁺⁺	98
SS-04	N4-(4-Cl)-Phe-Cyclo(D-Cys-Tyr-D-Trp-Lys-Thr-Cys)-D-Tyr-NH₂	1331.01	1329.56	1332 [M+H]⁺	98
SS-05	HYNIC-(4-Cl)-Phe-Cyclo(D-Cys-Tyr-D-Trp-Lys-Thr-Cys)-D-Tyr-NH₂	1279.88	1278.45	642 [M+2H]⁺⁺	97
SS-05		1279.88	1278.45	1280.8 [M+H]⁺	97