Isoluminol structure

Figure 4 Chemical structure of (A) luminol (5-amino-2,3- dihydro-l,4-phthalazinedi-one) and (B) isoluminol.

Fig. 13. Chemical structures of the chemiluminescent cyclic hydrazides luminol and isoluminol.

Fig. 14. Chemical structure of the popular isoluminol label ABEI (Al-aminobutyl-A -ethylisolu-...

While luminol and isoluminol require an oxidant plus a catalyst for initiation of the chemiluminescent reaction, esters derived from A -methyl acridinium carboxylic acid require only alkaline hydrogen peroxide (W4). Acridinium esters were first introduced by McCapra s group (M23, M25, S32), based on earlier work on the bioluminescence of the lucigenin/luciferase system (G18), and reviewed in McCapra and Beheshti (M21). From Fig. 19, one can see the structural similarity between lucigenin and a typical acridinium ester. 

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