  We have obtained Gemini/GMOS spectra of 28 regions located across the
interacting group NGC 6845, spanning from the inner regions of the four major
galaxies (NGC 6845A, B, C, D) to the tidal tails of NGC 6845A. All regions in
the tails are star-forming objects with ages younger than 10 Myr. We derived
the gas-phase metallicity gradients across NGC 6845A and its two tails and we
find that these are shallower than those for isolated galaxies. NGC 6845A has a
gas-phase oxygen central metallicity of \mbox{12+log(O/H)$\sim$8.5} and a flat
gas-phase metallicity gradient ($\beta$=0.002$\pm$0.004 dex kpc$^{-1}$) out to
$\sim$4 $\times$ R$_{25}$ (to the end of the longest tidal tail). Considering
the mass-metallicity relation, the central region of NGC 6845A displays a lower
oxygen abundance than the expected for its mass. Taking into account this fact
and considering the flat oxygen distribution measured along the eastern tidal
tail, we suggest that an interaction event has produced a dilution in the
central metallicity of this galaxy and the observed flattening in its metal
distribution. We found that the star formation process along the eastern tidal
structure has not been efficient enough to increase the oxygen abundances in
this place, suggesting that this structure was formed from enriched material.
