Mal-Propionyl-PEG8-Gly-Gly-Phe-Gly-PAB(m-PEG4)-PNP Size:25mg 98 SMILES: CC1(C)\C(=C/C=C/C2=[N+](CCCCCC(=O)NCCN3C(=O)C=CC3=O)C3=CC=C(C=C3C2(C)C)S(O)(=O)=O)N(CCCS([O-])(=O)=O)C2=CC=C(C=C12)S(O)(=O)=O Purity (HPLC):

98 SMILES: CC1(C)\C(=C/C=C/C2=[N+](CCCCCC(=O)NCCN3C(=O)C=CC3=O)C3=CC=C(C=C3C2(C)C)S(O)(=O)=O)N(CCCS([O-])(=O)=O)C2=CC=C(C=C12)S(O)(=O)=O Purity (HPLC): ≥ 95% Shipping Conditions: room temperature Storage Conditions: Refrigerated Regulatory Statement: For Research Use Only

Product Name: 5(6)-FAM ethylenediamine Synonyms: 5-(and 6)-carboxyfluorescein ethylenediamine CAS Number: N/A Molecular Formula: C25H19F3N2O8 (TFA salt) Molecular Weight: 532

493 SMILES O=C1N(C2CCC(=O)NC2=O)C(=O)C2=CC(OCCOCCOCCOCCOCC#C)=CC=C12 Purity (HPLC) >= 95% Shipping Conditions Room temperature Storage Conditions Refrigerated Shelf Life 12 months after the date of delivery Regulatory Statement For Research Use Only

34 Purity (HPLC) >= 95% Solubility DMSO

Product Name DBCO-Lys(m-PEG4)-Gly-Gly-Phe-Gly-PAB(m-PEG8)-Exatecan Synonyms CAS Number Related CAS Molecular Formula C100H125FN12O27 Molecular Weight 1946

Mal-Propionyl-PEG8-Gly-Gly-Phe-Gly-PAB(m-PEG4)-PNP Size:25mg 98 SMILES: CC1(C)\C(=C/C=C/C2=[N+](CCCCCC(=O)NCCN3C(=O)C=CC3=O)C3=CC=C(C=C3C2(C)C)S(O)(=O)=O)N(CCCS([O-])(=O)=O)C2=CC=C(C=C12)S(O)(=O)=O Purity (HPLC):SOLU KNEX cleavable linker features a Gly Gly Phe Gly (GGFG) peptide. The conventional maleimidocaproyl (MC) unit is replaced by Mal Propionyl PEG8 moiety to enhance aqueous solubility. The Mal Propionyl group may also improve retro Michael addition stability during antibody conjugation. m PEG4 is attached to the commonly used self immolative para aminobenzyl (PAB) moiety to increase aqueous solubility. The PNP (para nitrophenyl) moiety serves as an