  Over the past five decades, radio astronomy has shown that molecular
complexity is a natural outcome of interstellar chemistry, in particular in
star forming regions. However, the pathways that lead to the formation of
complex molecules are not completely understood and the depth of chemical
complexity has not been entirely revealed. In addition, the sulfur chemistry in
the dense interstellar medium is not well understood.
  We want to know the relative abundances of alkanethiols and alkanols in the
Galactic Center source Sagittarius B2(N2), the northern hot molecular core in
Sgr B2(N), whose relatively small line widths are favorable for studying the
molecular complexity in space.
  We investigated spectroscopic parameter sets that were able to reproduce
published laboratory rotational spectra of ethanethiol and studied effects that
modify intensities in the predicted rotational spectrum of ethanol. We used the
Atacama Large Millimeter Array (ALMA) in its Cycles~0 and 1 for a spectral line
survey of Sagittarius B2(N) between 84 and 114.4 GHz. These data were analyzed
by assuming local thermodynamic equilibrium (LTE) for each molecule. Our
observations are supplemented by astrochemical modeling; a new network is used
for the first time that includes reaction pathways for alkanethiols.
  The column density ratios involving methanol, ethanol, and methanethiol in
Sgr B2(N2) are similar to values reported for Orion KL, but those involving
ethanethiol are significantly different and suggest that the detection of
ethanethiol reported toward Orion KL is uncertain. Our chemical model presently
does not permit the prediction of sufficiently accurate column densities of
alkanethiols or their ratios among alkanethiols and alkanols. Therefore,
additional observational results are required to establish the level of C2H5SH
in the dense and warm interstellar medium with certainty.
