  The Scutum complex in the inner disk of the Galaxy hosts a number of young
clusters and associations of red supergiant stars that are heavily obscured by
dust extinction. These stars are important tracers of the recent star formation
and chemical enrichment history in the inner Galaxy. Within the SPA Large
Programme at the TNG, we secured GIANO-B high-resolution (R=50,000) YJHK
spectra of 11 red supergiants toward the Alicante 7 and Alicante 10
associations near the RSGC3 cluster. Taking advantage of the full YJHK spectral
coverage of GIANO in a single exposure, we were able to measure several
hundreds of atomic and molecular lines that are suitable for chemical abundance
determinations. We also measured a prominent diffuse interstellar band at
lambda=1317.8 nm (vacuum). This provides an independent reddening estimate. The
radial velocities, Gaia proper motions, and extinction of seven red supergiants
in Alicante 7 and three in Alicante 10 are consistent with them being members
of the associations. One star toward Alicante 10 has kinematics and low
extinction that are inconsistent with a membership. By means of spectral
synthesis and line equivalent width measurements, we obtained chemical
abundances for iron-peak, CNO, alpha, other light, and a few neutron-capture
elements. We found average slightly subsolar iron abundances and solar-scaled
[X/Fe] abundance patterns for most of the elements, consistent with a thin-disk
chemistry. We found depletion of [C/Fe], enhancement of [N/Fe], and relatively
low 12C/13C<15, which is consistent with CN cycled material and possibly some
additional mixing in their atmospheres.
