{TAIL ~ The coupling reagent} couples with this diazo compound to produce {HEAD ~ an azo dye} 
{ TAIL ~ The coupling reagent } couples with this diazo compound to produce { HEAD ~ an azo dye }
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD