[ Eq(Derivative(x1, t), ((-1)*k2*x1*x2 + 1*k1*x3 + 1*k10 + (-1)*k3*x1)/k11),
  Eq(Derivative(x2, t), ((-1)*k2*x1*x2 + 1*k1*x3)/k11),
  Eq(Derivative(x3, t), (1*k2*x1*x2 + (-1)*k1*x3 + (-1)*k6*x3*x5 + 1*k4*x4 + 1*k5*x4)/k11),
  Eq(Derivative(x4, t), (1*k6*x3*x5 + (-1)*k4*x4 + (-1)*k5*x4)/k11),
  Eq(Derivative(x5, t), ((-1)*k6*x3*x5 + 1*k4*x4 + 1*k7 + (-1)*k8*x5)/k11) ]