  Meson-baryon couplings between positive and negative parity baryons are
investigated using two point correlation functions in the soft meson limit. We
find that the pi NN^* coupling vanishes due to chiral symmetry, while the eta
NN^* coupling remains finite. We perform an analysis based on the algebraic
method for SU(2) and SU(3) chiral symmetry, and find that baryon axial charges
play an essential role for vanishing coupling constants.
