 
- 
                        N1,N2-bis[[(E)-(2-hydroxy-4-oxo-1-cyclohexa-2,5-dienylidene)methyl]amino]ethanediimidamideCAS:6343-51-7Formula:C16H16N6O4 
                     
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                        Propanedioic acid, (1H-pyrazolo[3,4-b]quinoxalin-3-ylhydrazono)-,
diethyl esterCAS:194033-29-9Formula:C16H16N6O4 
                     
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                        1,10-Diazacyclooctadeca-1,3,5,7,9,11,13,15,17-nonaene-5,6-diamine,
12,17-dinitro-CAS:202148-27-4Formula:C16H16N6O4 
                     
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                        Adenosine, 2'-deoxy-N-(2-pyridinylcarbonyl)-CAS:661463-48-5Formula:C16H16N6O4 
                     
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                        8-[(2E)-2-(1,3-benzodioxol-5-ylmethylidene)hydrazinyl]-1,3,7-trimethyl-3,7-dihydro-1H-purine-2,6-dioneCAS:6632-73-1Formula:C16H16N6O4 
                     
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                        Carbamic acid, [7-(4-nitrophenyl)[1,2,4]triazolo[1,5-a]pyrimidin-2-yl]-,
1,1-dimethylethyl esterCAS:850734-02-0Formula:C16H16N6O4 
                     
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                        Propanamide,
N-[6,7-dihydro-7-[(4-nitrophenyl)methyl]-6-oxo-1H-purin-2-yl]-2-methyl-CAS:869657-57-8Formula:C16H16N6O4 
                     
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                        N-[1-[[4-[4-[[1-(hydroxyamino)-2-nitroso-ethenyl]amino]phenyl]phenyl]amino]-2-nitroso-ethenyl]hydroxylamineCAS:87259-67-4Formula:C16H16N6O4 
                     
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                        Pyrimidinedione, 5,5'-[(4-methylphenyl)methylene]bis[6-amino-CAS:874349-19-6Formula:C16H16N6O4 
                     
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                        (3E)-1-ethyl-3-(3-hydroxy-4-oxocyclohexa-2,5-dien-1-ylidene)-9-methyl-1,2,3,4-tetrahydro[1,2,4]triazino[3,4-f]purine-6,8(7H,9H)-dioneCAS:105774-51-4Formula:C16H16N6O4