  The out-of-phase soliton distribution of the wave field was found for a
multicore fiber (MCF) from an even number of cores located in a ring. Its
stability is proved both with respect to small wave field perturbations,
including azimuthal ones and to small deformations of the MCF structure. As an
example of using this soliton distribution, the problem of laser pulse
compression in an active MCF is studied. The optimal fiber parameters, the
minimum duration of the output pulse, and the compression length have been
found, which are in good agreement with the results of numerical simulation. In
order to achieve high energies in the output laser pulse, the requirements for
MCF deformations are determined.
