O=C(NCCC1=CCCCC1)C1CCC(CNc2c(N3CCCC3)c(=O)c2=O)CC1
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?