Quantization of the $(\sin\varphi)_2$ interaction in terms of fermion variables

Quantization of the $(\sin\varphi)_2$-interaction is performed. It is shown that for the accepted quantization procedure, the Hamiltonian of the $(\sin\varphi)_2$-interaction is equivalent to the Hamiltonian of a fermion field which reduces at definite conditions to the Hamiltonian of the massive Thirring model.