73  US 9,256,127 B2  74  -continued  -continued  H  H  i  Fo  ~OH  HO~  HO  c+-I-J  J  Fo  0  HO  H  H  (++)  i  Fo  0  HO  OH  H  H  (++)  i  Fo  0  HO  H  H  HO  i  Fo  HO  HO  0  c+-I-J  J  Fo  0  H  H  (++)  i  Fo  0  c+-I-J  J  Fo  0  OH  OH  c+-I-J  J  Fo  0  OH  HO  c+-I-J  J  0  H  H  H  H  (++)  i  Fo  (++)  i  Fo  ~o  ~o  0  (++)  (++)  i  Fo  i  Fo  9  ~  0  0  H  H  H  H  (++)  i  Fo  (++)  i  Fo  0  0  Illustrative examples of the recurring units having formula  (C) are given below, but not limited thereto. 