With no explanation, label each line with "O", "other-chemicalthing", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
Furan-2-ylmethanethiol
is
easily
prepared
by
reacting
furfuryl
alcohol
with
thiourea
in
hydrochloric
acid
via
an
intermediate
isothiouronium
salt
which
is
hydrolized
to
the
thiol
by
heating
with
sodium
hydroxide
.
Furan-2-ylmethanethiol:other-chemicalthing
is:O
easily:O
prepared:O
by:O
reacting:O
furfuryl:other-chemicalthing
alcohol:other-chemicalthing
with:O
thiourea:other-chemicalthing
in:O
hydrochloric:other-chemicalthing
acid:other-chemicalthing
via:O
an:O
intermediate:other-chemicalthing
isothiouronium:other-chemicalthing
salt:other-chemicalthing
which:O
is:O
hydrolized:O
to:O
the:O
thiol:other-chemicalthing
by:O
heating:O
with:O
sodium:other-chemicalthing
hydroxide:other-chemicalthing
.:O