{ diff(x1, t) = (1*k23*k1/(1 + k9*x3^k14)*(k15 - x1)*k4/(1 + k11*x3^k14)*x1 + (-1)*k23*(1 - k1/(1 + k9*x3^k14))*k4/(1 + k11*x3^k14)*x1)/k23, diff(x2, t) = (2*k23*(1 - k1/(1 + k9*x3^k14))*k4/(1 + k11*x3^k14)*x1 + 1*k23*k2/(1 + k10*x3^k14)*(k16 - (x2 + x4))*k5/(1 + k12*x3^k14)*x2 + (-1)*k23*(1 - k2/(1 + k10*x3^k14))*k5/(1 + k12*x3^k14)*x2)/k23, diff(x3, t) = (2*k23*(1 - k2/(1 + k10*x3^k14))*k5/(1 + k12*x3^k14)*x2 + (-1)*k23*k7*x3)/k23, diff(x4, t) = (1*k23*k3*(k16 - (x2 + x4))*k6*x4 + (-1)*k23*(1 - k3)*k6*x4)/k23, diff(x5, t) = (2*k23*(1 - k3)*k6*x4 + (-1)*k23*k8*x5)/k23 }