Conformal field theory with background H-flux and T-duality

We consider closed bosonic string theory with flat background and constant H-flux. Up to linear order in the flux, this is a solution to the string equations of motion and we are able to define a world-sheet conformal field theory framework to compute scattering amplitudes. In the easiest cases of n-point tachyon amplitudes, we use the properties of the Rogers dilogarithm function to speculate about the nature of the product of functions on spacetimes T-dual to the original configuration.