ALMA Observations of Molecular Complexity in the Large Magellanic Cloud:
  The N105 Star-Forming Region
  The Large Magellanic Cloud (LMC) is the nearest laboratory for detailed
studies on the formation and survival of complex organic molecules (COMs),
including biologically important ones, in low-metallicity environments--typical
for earlier cosmological epochs. We report the results of 1.2 mm continuum and
molecular line observations of three fields in the star-forming region N105
with the Atacama Large Millimeter/submillimeter Array (ALMA). N105 lies at the
western edge of the LMC bar with on-going star formation traced by H$_2$O, OH,
and CH$_3$OH masers, ultracompact H II regions, and young stellar objects.
Based on the spectral line modeling, we estimated rotational temperatures,
column densities, and fractional molecular abundances for twelve 1.2 mm
continuum sources. We identified sources with a range of chemical make-ups,
including two bona fide hot cores and four hot core candidates. The CH$_3$OH
emission is widespread and associated with all the continuum sources. COMs
CH$_3$CN and CH$_3$OCH$_3$ are detected toward two hot cores in N105 together
with smaller molecules typically found in Galactic hot cores (e.g., SO$_2$, SO,
and HNCO) with the molecular abundances roughly scaling with metallicity. We
report a tentative detection of the astrobiologically relevant formamide
molecule (NH$_2$CHO) toward one of the hot cores; if confirmed, this would be
the first detection of NH$_2$CHO in an extragalactic sub-solar metallicity
environment. We suggest that metallicity inhomogeneities resulting from the
tidal interactions between the LMC and the Small Magellanic Cloud (SMC) might
have led to the observed large variations in COM abundances in LMC hot cores.
