(\beta\circ\partial_{\sqrt{q}}\circ\mathcal A^{-0}\circ\mathcal B)(f_0)\ \text{modulo $\mathrm U(\mathfrak g)\cdot \mathfrak k^{-\delta+\frac{0}0\mathrm{tr}_\mathfrak g\circ\mathrm{ad}}$},$$ for $f_i$