  Although first considered as too diluted for the formation of molecules
in-situ and too harsh an environment for their survival, the interstellar
medium has turned out to host a rich palette of molecular species: to date, 256
species have been identified. The last decade has seen an explosion of new
detections, including those of a number of complex organic species, which may
be dubbed as prebiotic. Organic molecules have been discovered not just in
interstellar clouds from the Solar neighbourhood, but also throughout the
Milky-Way, as well as in nearby galaxies, or some of the most distant quasars.
These discoveries were made possible by the completion of large sub-millimetre
and radio facilities. Equipped with new generation receivers, those instruments
have provided the orders of magnitude leap in sensitivity required to detect
the weak rotational lines that allowed the molecule identifications. Last two
years, 30 prebiotic molecules have been detected in TMC-1, a dust-enshrouded
gaseous cloud located at 400 light-years from the Sun in the Taurus
constellation. Ten new molecular species, have been identified in the arm of a
spiral galaxy 6 billion light-yr distant, and 12 molecular species observed in
a quasar at 11 billion light-yr. We present the latest spectral observations of
this outlying quasar and discuss the implications of those detections in these
3 archetypal sources. The basic ingredients involved in the Miller-Urey
experiment and related experiments appeared early after the formation of the
first galaxies and are widespread throughout the Universe. The chemical
composition of the gas in distant galaxies seems not much different from that
in the nearby interstellar clouds. It presumably comprises, like for TMC-1,
aromatic rings and complex organic molecules putative precursors of the RNA
nucleobases, except the lines of such species are too weak to be detected that
far.
