Portion of the EMoCA survey around 102.2 GHz. The best-fit LTE synthetic spectrum that contains the contributions of all molecules identified so far towards Sgr B2(N2) is overlaid in green on the observed spectrum, which is shown in black. The synthetic spectrum of imidazole used to derived the upper limit on its column density is shown in red. The y-axis is labelled in brightness temperature units. The dotted line indicates the 3σ noise level.