| abstract |
Compounds and pharmaceutically acceptable salts of the compounds are disclosed, wherein the compounds have the structure of Formula I: n n n n n n n n n n wherein A 1 , A 2 , A 3 , A 4 , A 5 , A 6 , A 7 , A 8 , X 4 , X 6 , R 2 , R 4 , R 5 , and R 6 are as defined in the detailed description of the invention. Corresponding pharmaceutical compositions, methods of treatment, methods of synthesis, and intermediates are also disclosed. |