Structurally, the reducible compounds are aromatic derivatives or {HEAD ~ quinones} having {TAIL ~ suitable substituents} which promote varying amounts of moiety release at physiological pH. When reduced at about pH 7, the preferred compounds release at least 50% of the available detectable species within 30 minutes 
Structurally , the reducible compounds are aromatic derivatives or { HEAD ~ quinones } having { TAIL ~ suitable substituents } which promote varying amounts of moiety release at physiological pH. When reduced at about pH 7 , the preferred compounds release at least 50 % of the available detectable species within 30 minutes
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH