Browse reference spectra from the USGS Spectral Library Version 7 and other curated sources. Each spectrum includes interactive plots, metadata, and downloadable data.
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| Formula | Modality | Category | Source | ||
|---|---|---|---|---|---|
| 4' 5 7-trihydroxyflavanone | C15H12O5 | Mass Spec | Chemical | MassBank | |
| 4' 5 7-trihydroxyflavone | C15H10O5 | Mass Spec | Chemical | MassBank | |
| 4' 5 7-trihydroxyisoflavone | C15H10O5 | Mass Spec | Chemical | MassBank | |
| 4' 7-dihydroxyisoflavone | C15H10O4 | Mass Spec | Chemical | MassBank | |
| 4',5'-Dibromofluorescein | C20H10Br2O5 | Mass Spec | Chemical | MassBank | |
| 4',5,7-TRIACETOXYFLAVONE | C21H16O8 | Mass Spec | Chemical | MassBank | |
| 4',5,7-TRIHYDROXY-3'-(3-METHYL-2-BUTENYL)ISOFLAVONE | C20H18O5 | Mass Spec | Chemical | MassBank | |
| 4',5,7-TRIHYDROXYFLAVONOL | C15H10O6 | Mass Spec | Chemical | MassBank | |
| 4',5,7-trihydroxyflavanone | C15H12O5 | Mass Spec | Natural product | MassBank | |
| 4',5,7-trihydroxyflavone | C15H10O5 | Mass Spec | Natural product | MassBank | |
| 4',5,7-trihydroxyisoflavone | C15H10O5 | Mass Spec | Natural product | MassBank | |
| 4',5-DIHYDROXY-7-METHOXYFLAVANONE | C16H14O5 | Mass Spec | Chemical | MassBank | |
| 4',5-bisdeoxy-dothistromin | C18H12O7 | Mass Spec | Metabolite | MassBank | |
| 4',5-dihydroxy-7-methoxyflavone | C16H14O5 | Mass Spec | Chemical | MassBank | |
| 4',6,7-TRIMETHOXYFLAVONOL | C18H16O6 | Mass Spec | Chemical | MassBank | |
| 4',7-DIMETHOXYFLAVONE | C17H14O4 | Mass Spec | Chemical | MassBank | |
| 4',7-DIMETHOXYFLAVONOL | C17H14O5 | Mass Spec | Chemical | MassBank | |
| 4',7-dihydroxyisoflavone | C15H10O4 | Mass Spec | Natural product | MassBank | |
| 4'-ACETAMINO-6-METHYLFLAVANONE | C18H17NO3 | Mass Spec | Chemical | MassBank | |
| 4'-ACETOAMINO-5,7-DIMETHYLFLAVANONE | C19H19NO3 | Mass Spec | Chemical | MassBank | |
| 4'-ACETOXY-5,7-DIMETHYLFLAVANONE | C19H18O4 | Mass Spec | Chemical | MassBank | |
| 4'-AMINO-5,7-DIMETHYLFLAVANONE | C17H17NO2 | Mass Spec | Chemical | MassBank | |
| 4'-BROMO-6-CARBOXYFLAVONOL | C16H9BrO5 | Mass Spec | Chemical | MassBank | |
| 4'-BROMOACETOPHENONE | C8H7BrO | Mass Spec | Chemical | MassBank | |
| 4'-Chloro-2',5'-dimethoxyacetoacetanilide | C12H14ClNO4 | Mass Spec | Chemical | MassBank | |
| 4'-Chloroacetoacetanilide | C10H10ClNO2 | Mass Spec | Chemical | MassBank | |
| 4'-Fluoro-4-aminodiphenyl | C12H10FN | Mass Spec | Environmental | MassBank | |
| 4'-HYDROXY-6,8-DIMETHYLFLAVANONE | C17H16O3 | Mass Spec | Chemical | MassBank | |
| 4'-HYDROXY-6,8-DIMETHYLFLAVONE | C17H14O3 | Mass Spec | Chemical | MassBank | |
| 4'-HYDROXYACETOPHENONE | C8H8O2 | Mass Spec | Chemical | MassBank | |
| 4'-Hydroxyechinenone | C40H54O2 | Mass Spec | Natural product | MassBank | |
| 4'-Hydroxyflavone | C15H10O3 | Mass Spec | Natural product | MassBank | |
| 4'-METHOXY-6,8-DIMETHYLFLAVONOL | C18H16O4 | Mass Spec | Chemical | MassBank | |
| 4'-METHOXYCHALCONE | C16H14O2 | Mass Spec | Chemical | MassBank | |
| 4'-METHOXYFLAVONE | C16H12O3 | Mass Spec | Chemical | MassBank | |
| 4'-Methyl-alpha-pyrrolidinopropiophenone | C14H19NO | Mass Spec | Environmental | MassBank | |
| 4'-NITROFLAVANONE | C15H11NO4 | Mass Spec | Chemical | MassBank | |
| 4'-O-(2'-E-Coumaroyl GluA)(1-2)GluA) Apigenin (NMR) | C36H32O19 | Mass Spec | Natural product | MassBank | |
| 4'-O-(2'-E-Feruloyl GluA(1-2)GluA) Apigenin (NMR) | C37H34O20 | Mass Spec | Natural product | MassBank | |
| 4'-O-(2'-Z-Coumaroyl GluA)(1-2)GluA) Apigenin (NMR) | C36H32O19 | Mass Spec | Natural product | MassBank | |
| 4'-O-(2'-Z-Feruloyl GluA(1-2)GluA) Apigenin (NMR) | C37H34O20 | Mass Spec | Natural product | MassBank | |
| 4'-O-(GlcA(1-2)GlcA) Apigenin (NMR) | C27H26O17 | Mass Spec | Natural product | MassBank | |
| 4'-O-(Glucuronyl-(1-3)-2'-E-Feruloyl-O-glucuronyl)-(1-2)-glucuronyl Apigenin (NMR) | C43H42O26 | Mass Spec | Natural product | MassBank | |
| 4'-O-Demethyl pantoprazole sulfide | C15H13F2N3O3S | Mass Spec | Pharmaceutical | MassBank | |
| 4'-O-GlcA-7-O-GlcA Apigenin (NMR) | C27H26O17 | Mass Spec | Natural product | MassBank | |
| 4'-Sulfamylacetanilide | C8H10N2O3S | Mass Spec | Environmental | MassBank | |
| 4'-TERT-BUTYL-2',6'-DIMETHYL-3',5'-DINITROACETOPHENONE | C14H18N2O5 | Mass Spec | Chemical | MassBank | |
| 4(3H)-PYRIMIDONE | C4H4N2O | Mass Spec | Chemical | MassBank | |
| 4(8)-PARA-MENTHEN-3-YL ACETATE | C12H20O2 | Mass Spec | Chemical | MassBank | |
| 4,(6or7)-dimethyl benzotriazole (Tentative) | C8H9N3 | Mass Spec | Chemical | MassBank |