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-AMINO-2,3-DIMETHYL-1-PHENYL-3-PYRAZOLIN-5-ONE | C11H13N3O | Mass Spec | Chemical | MassBank | |
| 4-AMINO-2-METHYLPYRIMIDINE | C5H7N3 | Mass Spec | Chemical | MassBank | |
| 4-AMINO-5-CYANO-2-METHYLPYRIMIDINE | C6H6N4 | Mass Spec | Chemical | MassBank | |
| 4-AMINO-ANTIPYRINE | C11H13N3O | Mass Spec | Chemical | MassBank | |
| 4-AMINOANTIPYRIN | C11H13N3O | Mass Spec | Chemical | MassBank | |
| 4-AMINOBENZONITRILE | C7H6N2 | Mass Spec | Chemical | MassBank | |
| 4-AMINOBENZOPHENONE | C13H11NO | Mass Spec | Chemical | MassBank | |
| 4-AMINOBENZYL CYANIDE | C8H8N2 | Mass Spec | Chemical | MassBank | |
| 4-AMINOBUTYRIC ACID | C4H9NO2 | Mass Spec | Chemical | MassBank | |
| 4-AMINODIPHENYL | C12H11N | Mass Spec | Chemical | MassBank | |
| 4-AMINOHIPPURIC ACID | C9H10N2O3 | Mass Spec | Chemical | MassBank | |
| 4-AMINOPHENYL DISULFIDE | C12H12N2S2 | Mass Spec | Chemical | MassBank | |
| 4-AMINOPYRIDINE | C5H6N2 | Mass Spec | Chemical | MassBank | |
| 4-ANILINO-7-CHLORO QUINAZOLINE | C14H10ClN3 | Mass Spec | Chemical | MassBank | |
| 4-AZIDOBENZOIC ACID CYCLOHEXYL ESTER | C13H15N3O2 | Mass Spec | Chemical | MassBank | |
| 4-Acetamidoantipyrin | C13H15N3O2 | Mass Spec | Environmental | MassBank | |
| 4-Acetamidoantipyrine | C13H15N3O2 | Mass Spec | Pharmaceutical | MassBank | |
| 4-Acetamidobenzoic acid | C9H9NO3 | Mass Spec | Pharmaceutical | MassBank | |
| 4-Acetamidophenol | C8H9NO2 | Mass Spec | Environmental | MassBank | |
| 4-Acetamidophenyl D-glucopyranosiduronic acid | C14H17NO8 | Mass Spec | Pharmaceutical | MassBank | |
| 4-Acetylaminophenylacetic acid | C10H11NO3 | Mass Spec | Chemical | MassBank | |
| 4-Acetylbenzoic acid | C9H8O3 | Mass Spec | Pharmaceutical | MassBank | |
| 4-Acetylbutyrate | C6H10O3 | Mass Spec | Chemical | MassBank | |
| 4-Allyl-2-(4-methoxyphenyl)-5,5-dimethyl-1,3-dioxane | C16H22O3 | Mass Spec | Natural product | MassBank | |
| 4-Amino-1,2,4-triazole | C2H4N4 | Mass Spec | Chemical | MassBank | |
| 4-Amino-2,5-dimethoxy-N-phenylbenzenesulfonamide | C14H16N2O4S | Mass Spec | Environmental | MassBank | |
| 4-Amino-2,6-dimethoxypyrimidine | C6H9N3O2 | Mass Spec | Pharmaceutical | MassBank | |
| 4-Amino-6-Chloro-1,3-Benzenedisulfonamide | C6H8ClN3O4S2 | Mass Spec | Pharmaceutical | MassBank | |
| 4-Amino-6-tert-butyl-3-thioxo-3,4-dihydro-1,2,4-triazin-5(2H)-one | C7H12N4OS | Mass Spec | Chemical | MassBank | |
| 4-Amino-N,N-dimethylbenzenesulfonamide | C8H12N2O2S | Mass Spec | Environmental | MassBank | |
| 4-Aminoantipyrine | C15H23NO2 | Mass Spec | Environmental | MassBank | |
| 4-Aminoazobenzene | C12H11N3 | Mass Spec | Chemical | MassBank | |
| 4-Aminobenzamide | C7H8N2O | Mass Spec | Environmental | MassBank | |
| 4-Aminobenzoic acid | C7H7NO2 | Mass Spec | Natural product | MassBank | |
| 4-Aminobutanoate | C4H9NO2 | Mass Spec | Natural product | MassBank | |
| 4-Aminobutanoic acid | C4H9NO2 | Mass Spec | Chemical | MassBank | |
| 4-Aminoindole | C8H8N2 | Mass Spec | Chemical | MassBank | |
| 4-Aminophenol | C6H7NO | Mass Spec | Environmental | MassBank | |
| 4-Aminophenylsulfone | C12H12N2O2S | Mass Spec | Chemical | MassBank | |
| 4-Aminosalicylate | C7H7NO3 | Mass Spec | Chemical | MassBank | |
| 4-Aminosalicylic acid | C7H7NO3 | Mass Spec | Pharmaceutical | MassBank | |
| 4-Androsten-11beta-ol-3,17-dione | C19H26O3 | Mass Spec | Environmental | MassBank | |
| 4-Androstene-3,17-dione | C19H26O2 | Mass Spec | Environmental | MassBank | |
| 4-Anilinophenol | C12H11NO | Mass Spec | Chemical | MassBank | |
| 4-BENZOYL-2,6-DIPHENYLPYRIDINE | C24H17NO | Mass Spec | Chemical | MassBank | |
| 4-BENZOYL-3,5-DIMETHYLISOXAZOLE | C12H11NO2 | Mass Spec | Chemical | MassBank | |
| 4-BENZOYL-3-PHENYL-5-ISOXAZOLONE | C16H11NO3 | Mass Spec | Chemical | MassBank | |
| 4-BENZOYL-6-PHENYL-2H-PYRAN-2-ONE | C18H12O3 | Mass Spec | Chemical | MassBank | |
| 4-BENZOYLBUTYRIC ACID | C11H12O3 | Mass Spec | Chemical | MassBank | |
| 4-BENZOYLOXY-1-(2-BENZOYLOXYETHYL)CYCLOHEXAN-1-OL | C22H24O5 | Mass Spec | Chemical | MassBank |