[1]Patent:US2015/23989,2015,A1
[2]Patent:US2015/246136,2015,A1
[3]Patent:CN109200291,2019,A
[1]Patent:CN109200291,2019,A
Title: Michinori Akaiwa, et al. Synthesis and Evaluation of Linear and Macrocyclic Dolastatin 10 Analogues Containing Pyrrolidine Ring Modifications. ACS Omega. 2018 May 31;3(5):5212-5221.