What do you mean by biologically important compounds?

Question

what do you mean by biologically important compounds?What is its importance...?

Answer 1

I think you usually mean the basic molecules that compose all the biological (macro)molecules, i.e. nucleotides, lipids, aminoacids, C/H).

Answer 2

I think you may be talking about the recent news about our latest Mars mission where the lander has found water and biologically important compounds.  What this means is there are compounds that we think are important for the potential of life to be created.  In a nutshell the scientists think that similar conditions also may have existed on mars that were on earth when life came forth.