\frac{dx_{1}}{dt} = \left(1 \cdot k_{1} \cdot k_{4} \cdot x_{3} / \left(k_{2} + x_{3}\right) \cdot x_{4} / \left(k_{3} + x_{4}\right) + 1 \cdot k_{1} \cdot k_{5} \cdot x_{5} + 1 \cdot k_{1} \cdot k_{6} + -1 \cdot k_{1} \cdot k_{7} \cdot x_{1}\right) / k_{1}\\
\frac{dx_{2}}{dt} = \left(-1 \cdot k_{1} \cdot k_{11} \cdot x_{2} + 1 \cdot k_{1} \cdot k_{18} \cdot x_{6} / \left(k_{19} + x_{6}\right) \cdot x_{5} / \left(k_{20} + x_{5}\right) \cdot x_{3} / \left(k_{21} + x_{3}\right)\right) / k_{1}\\
\frac{dx_{4}}{dt} = \left(-1 \cdot k_{1} \cdot k_{12} \cdot x_{4} + 1 \cdot k_{1} \cdot k_{14} \cdot x_{2}\right) / k_{1}\\
\frac{dx_{5}}{dt} = \left(-1 \cdot k_{1} \cdot k_{10} \cdot x_{5} + 1 \cdot k_{1} \cdot k_{15} \cdot x_{7}\right) / k_{1}\\
\frac{dx_{6}}{dt} = \left(-1 \cdot k_{1} \cdot k_{8} \cdot x_{6} + 1 \cdot k_{1} \cdot k_{13} \cdot x_{1}\right) / k_{1}\\
\frac{dx_{7}}{dt} = \left(-1 \cdot k_{1} \cdot k_{9} \cdot x_{7} + 1 \cdot k_{1} \cdot k_{16} \cdot x_{6} \cdot k_{17} / \left(k_{17} + x_{3}\right)\right) / k_{1}