Cc1cc(=O)oc2c3c(cc(OCC(=O)NCCC(=O)O)c12)OC(C)(C)CC3
A rotatable bond is defined as any single non-ring bond, attached to a non-terminal, non-hydrogen atom. Amide C-N bonds are not counted because of their high barrier to rotation.  How many rotatable bonds does the molecule have?