S1 Supporting Information Exploration of Pyrrolobenzodiazepine(PBD)-dimers Containing Disulfide-based Prodrugs as Payloads for Antibody-Drug Conjugates Zhonghua Pei, †,‡ Chunjiao Chen, ║ Jinhua Chen, § Josefa dela Cruz-Chuh, † Reginald Delarosa, † Yuzhong Deng, † Aimee Fourie-O’Donohue, † Isabel Figueroa, † Jun Guo, † Weiwei Jin, ║ S. Cyrus Khojasteh, † Katherine R. Kozak, † Brandon Latifi, † James Lee, † Guangmin Li, † Eva Lin, † Liling Liu, † Jiawei Lu, ║ Scott Martin, † Carl Ng, † Trung Nguyen, † Rachana Ohri, † Gail Lewis Phillips, † Thomas H. Pillow, † Rebecca K. Rowntree, † Nicola J. Stagg, † David Stokoe, †, ┴ Sheila Ulufatu, † Vishal A. Verma, † John Wai, § Jing Wang, § Keyang Xu, † Zijin Xu, § Hui Yao, § Shang-Fan Yu, † Donglu Zhang, † Peter S. Dragovich* ,† † Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA ‡ Present address: Ideaya Biosciences, 7000 Shoreline Court, South San Francisco, CA 94080, USA § Wuxi Apptec, 288 Fute Zhong Road, Waigaoqiao Free Trade Zone, Shanghai 200131, China ║ WuXi Biologics, 288 Fute Zhong Road, Waigaoqiao Free Trade Zone, Shanghai 200131, China ┴Present address: Calico Inc., 1170 Veterans Blvd, South San Francisco, CA, 94080, USA