US  2020/0050105  Al  77  Feb. 13, 2020  -continued  xi  xi  xi  O~C-S03- xi  OH  2  0  xi  xi  xi  CF2  o~r  \03- OH  0  xi  xi  xi  -continued  xi  xi  xi  xi  xi  O~-S03- xi  0  0  xi  xi  xi  o~o~-s0 3 - OH  0  xi  xi  xi  o~o~-s0 3 - OH  0  xi  xi  xi  o~o~-s0 3 - xi  OH  0  0 