Mal-Propionyl-PEG8-Gly-Gly-Phe-Gly-PAB(m-PEG4)-MMAE Size:25mg 94 SMILES CC1=C(SC=N1)C1=CC=C(CNC(=O)[C@@H]2C[C@@H](O)CN2C(=O)[C@@H](NC(=O)COCCOCCOCCOCCOCCOCCN=[N+]=[N-])C(C)(C)C)C=C1 Purity (HPLC)

94 SMILES CC1=C(SC=N1)C1=CC=C(CNC(=O)[C@@H]2C[C@@H](O)CN2C(=O)[C@@H](NC(=O)COCCOCCOCCOCCOCCOCCN=[N+]=[N-])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

Product Name Pomalidomide-PEG4-C2-Br Synonyms Pomalidomide-4'-PEG4-C2-Br CAS Number n/a Related CAS Molecular Formula C23H30BrN3O8 Molecular Weight 556

99 SMILES ClCCOCCOCCOCCOCCOCCOC1=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

741 Purity (HPLC) >= 95% Physical Appearance Dark Purple Solid Optical Properties Abs/Em Maxima: 555/585 nm Solubility DMSO

Mal-Propionyl-PEG8-Gly-Gly-Phe-Gly-PAB(m-PEG4)-MMAE Size:25mg 94 SMILES CC1=C(SC=N1)C1=CC=C(CNC(=O)[C@@H]2C[C@@H](O)CN2C(=O)[C@@H](NC(=O)COCCOCCOCCOCCOCCOCCN=[N+]=[N-])C(C)(C)C)C=C1 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 payload is monomethyl auristatin E (MMAE), a