(Z)-(1-benzylpyridin-1-ium-4-yl)(5,6-dimethoxy-1-oxo-1H-inden-2(3H)-ylidene)methanolate, potassium salt (hydrobromide)

(Z)-(1-benzylpyridin-1-ium-4-yl)(5,6-dimethoxy-1-oxo-1H-inden-2(3H)-ylidene)methanolate, potassium salt (hydrobromide)