[ Eq(Derivative(x1, t), 0),
  Eq(Derivative(x2, t), (1*k31*(k1 + k2*k3) + (-1)*k32*k4*x2**2/(k5**2 + x2**2) + 1*k33*k6*x3**4*x4**2*x2**k7/((k8**4 + x3**4)*(k9**2 + x4**2)*(k10**k7 + x2**k7)) + 1*k33*k11*x4 + (-1)*k32*k12*x2)/k32),
  Eq(Derivative(x3, t), (1*k32*k3*k13 + (-1)*k32*k14*x3**k30*x2**k15/((k16**k30 + x3**k30)*(k17**k15 + x2**k15)) + (-1)*k32*k18*x3)/k32),
  Eq(Derivative(x4, t), (1*k32*k4*x2**2/(k5**2 + x2**2) + (-1)*k33*k6*x3**4*x4**2*x2**k7/((k8**4 + x3**4)*(k9**2 + x4**2)*(k10**k7 + x2**k7)) + (-1)*k33*k11*x4)/k33),
  Eq(Derivative(x5, t), (1*k32*k19*(1 + k20*x2**4/(k21**4 + x2**4))*(1 - x5)/(k22/(1 + x2**4/k23**4) + 1 - x5) + (-1)*k32*k24*(1 + k25*k26/(k27 + k26))*x5/(k28/(1 + k26/k29) + x5))/k32) ]