Complex sentence: The methylglyoxal molecule consists of two carbonyl groups flanked by a hydrogen atom and a methyl group; its carbonyl carbons will be denoted as C 1 and C 2, respectively.
Split into simpler sentences: The methylglyoxal molecule consists of two carbonyl groups flanked by a hydrogen atom and a methyl group. In the discussion below, these two carbonyl carbons will be denoted as C 1 and C 2, respectively.