[ Eq(Derivative(x1, t), (1*k36*x1*k1*1/(1 + (k30*x1 + k31*x3)**2)*x6 + (-1)*k36*k4*x1 + (-1)*k36*k2*x1 + (-1)*k36*k9*x6*x1)/k36),
  Eq(Derivative(x2, t), (1*k36*k2*k3*x1 + (-1)*k36*k5*x2)/k36),
  Eq(Derivative(x3, t), (1*k36*k9*x6*x1 + 1*k36*k11*1/(1 + (k32*x1 + k33*x3)**2)*x6*x3 + (-1)*k36*k34*x3 + (-1)*k36*k29*x3)/k36),
  Eq(Derivative(x4, t), (1*k36*k29*k28*x3 + (-1)*k36*k35*x4)/k36),
  Eq(Derivative(x5, t), (1*k36*k4*x1 + 1*k36*k5*x2 + 1*k36*k34*x3 + 1*k36*k35*x4 + (-1)*k36*k19*x5*x6)/k36),
  Eq(Derivative(x6, t), (1*k36*k18*x5 + (-1)*k36*k8*x6 + 1*k36*k10)/k36) ]