Cc1n[nH]c(S/C(=C/c2ccc(-c3ccc(C(=O)O)cc3)o2)C(=O)O)n1
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?