Azide-Lys(m-PEG4)-Gly-Gly-Phe-Gly-PAB(m-PEG4)-MMAE dacf1 653 SMILES OC(=O)CN1CCN(CC(O)=O)CCN(CC(=O)NCCCNC(=O)CCN2C(=O)C=CC2=O)CCN(CC(O)=O)CC1 Purity (HPLC)

653 SMILES OC(=O)CN1CCN(CC(O)=O)CCN(CC(=O)NCCCNC(=O)CCN2C(=O)C=CC2=O)CCN(CC(O)=O)CC1 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

197 Purity (HPLC) >= 95% Solubility DMSO

83 SMILES CC1=C(SC=N1)C1=CC=C(CNC(=O)[C@@H]2C[C@@H](O)CN2C(=O)[C@@H](NC(=O)CCCCCCCCCC(O)=O)C(C)(C)C)C=C1 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

324 SMILES O=C1N(C2CCC(=O)NC2=O)C(=O)C2=CC(NCCC#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

497 SMILES OCCOCCOCCOCCOCCOC1=C2C(=O)N(C3CCC(=O)NC3=O)C(=O)C2=CC=C1 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

Azide-Lys(m-PEG4)-Gly-Gly-Phe-Gly-PAB(m-PEG4)-MMAE dacf1 653 SMILES OC(=O)CN1CCN(CC(O)=O)CCN(CC(=O)NCCCNC(=O)CCN2C(=O)C=CC2=O)CCN(CC(O)=O)CC1 Purity (HPLC)SOLU KNEX cleavable linker features a Gly Gly Phe Gly (GGFG) peptide. In this product, a Azide Lys(m PEG4) moiety replaces the conventional maleimidocaproyl (MC) unit to enhance aqueous solubility. The azide functional group is widely utilized in bioconjugation via click chemistry to enable efficient and selective attachment of biomolecules. Additionally, m PEG4 is attached to the commonly used self immolative para aminobenzyl (PAB) moiety to further