| prov:value
| - Rb, Rb???, Rb???, Rc, Rc??? and Rc??? each preferably independently represents an alkylene group having from 1 to 12 carbon atoms, and particularly preferably an alkylene group having from 1 to 6 carbon atoms (e.g., a methylene group, an ethylene group, a propylene group, a butylene group, or a hexylene group).
|