| abstract |
Compounds useful as biologically active compounds are disclosed. The compounds have the following structure (I): or stereoisomers, tautomers thereofOr a salt thereof, wherein R 1 、R 2 、R 3 、R 4 、R 5 、L a 、L b 、L 1 、L 2 、L 3 M, m and n are as defined herein. Also provided are methods relating to their preparation and uses of such compounds. |