{HEAD ~ In particular, sulfonated aminocoumarins} that are useful as {TAIL ~ fluorescent tracing agents} and enzyme substrates, reactive derivatives of sulfonated aminocoumarins useful as labels, and their conjugates 
are useful as
{ HEAD ~ In particular , sulfonated aminocoumarins } that are useful as { TAIL ~ fluorescent tracing agents } and enzyme substrates , reactive derivatives of sulfonated aminocoumarins useful as labels , and their conjugates
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH