[ Eq(Derivative(x1, t), 1*(k6*(1 - x1) + 2*(k4*x4 - k3*x3**2))/k46),
  Eq(Derivative(x4, t), 1*(k3*x3**2 - (k4 + k5)*x4)/k46),
  Eq(Derivative(x6, t), 1*k9*(x5 - x6)/k46),
  Eq(Derivative(x8, t), 1*k12*((1 + k13)*x7 - (1 + k13*x7)*x8)/k46),
  Eq(Derivative(x9, t), 1*k14*(x8 - x9/(1 + x11/k18 + x12/k24))/k46),
  Eq(Derivative(x10, t), 1*k15*((1 + k16)*x6/(1 + k16*x6) - x10/(1 + x11/k20 + x12/k26))/k46),
  Eq(Derivative(x11, t), 1*(k21*x12/(1 + x12/k22 + x13/k28) - k17*x9*x11/(1 + x11/k18 + x12/k24) - k19*x10*x11/(1 + x11/k20 + x12/k26))/k46),
  Eq(Derivative(x13, t), 1*(k23*x9*x12/(1 + x11/k18 + x12/k24) + k25*x10*x12/(1 + x11/k20 + x12/k26) - k27*x13/((1 + x14/k30 + x15/k34)*(1 + x12/k22) + x13/k28))/k46),
  Eq(Derivative(x14, t), 1*(k31*x19*x15/(1 + x15/k32 + x16/k36) - k29*x13*x14/(1 + x14/k30 + x15/k34))/k46),
  Eq(Derivative(x16, t), 1*(k33*x13*x15/(1 + x14/k30 + x15/k34) - k35*x19*x16/(1 + x15/k32 + x16/k36))/k46),
  Eq(Derivative(x17, t), 1*k37*((1 - x17)/k40 - x16**k39/(k38**k39 + x16**k39)*x17)/k46),
  Eq(Derivative(x18, t), 1*k41*(x16 - x18)/k46),
  Eq(Derivative(x19, t), 1*k42*(x18**k44/(k43**k44 + x18**k44) - (x19 - 1)/k45)/k46) ]