#$%^&*AU2016202473A120160512.pdf#####ABSTRACT A compound which is either A: H N N O0 0 HH o OH H N N H N N HB o 0 g O h 0 H - H"-' 0-N 0 0 0 0 H N H~ 0 0 HY HH lH,,, N- H 0 0 B and salts and solvates thereof, as well as conjugates thereof with cell binding agent.