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-CYANO-5-METHYL-6-PHENYL-2-(PARA-TOLYL)PERHYDROPYRROLO(3,4-C)PYRROLE-1,3-DIONE (3A,4-TRANS-6,6A-CIS) | C21H19N3O2 | Mass Spec | Chemical | MassBank | |
| 4-CYANO-5-METHYL-6-PHENYL-2-(PARA-TOLYL)PERHYDROPYRROLO(3,4-C)PYRROLE-1,3-DIONE (3A,4-TRANS-6,6A-TRANS) | C21H19N3O2 | Mass Spec | Chemical | MassBank | |
| 4-CYANO-6-(4-FLUOROPHENYL)PYRIMIDINE | C11H6FN3 | Mass Spec | Chemical | MassBank | |
| 4-CYANOBENZALDOXIME | C8H6N2O | Mass Spec | Chemical | MassBank | |
| 4-CYANOBENZYL BENZOATE | C15H11NO2 | Mass Spec | Chemical | MassBank | |
| 4-CYANOMETHYL-3-METHYL-1-PARA-TOLYL-3-PYRROLINE-2,5-DIONE | C14H12N2O2 | Mass Spec | Chemical | MassBank | |
| 4-CYCLOHEXENYL-3-METHYLBUTENE | C11H18 | Mass Spec | Chemical | MassBank | |
| 4-CYCLOHEXYL-4-METHYL-2-PENTANONE | C12H22O | Mass Spec | Chemical | MassBank | |
| 4-Carboxy-9-acridanone | C14H9NO3 | Mass Spec | Pharmaceutical | MassBank | |
| 4-Chloro-2-methylphenol | C7H7ClO | Mass Spec | Chemical | MassBank | |
| 4-Chloro-3-nitroaniline | C6H5ClN2O2 | Mass Spec | Chemical | MassBank | |
| 4-Chloro-N,N-Dimethylbenzamide | C9H10ClNO | Mass Spec | Chemical | MassBank | |
| 4-Chloroaniline | C6H6ClN | Mass Spec | Environmental | MassBank | |
| 4-Chlorobenzenesulfonamide | C6H6ClNO2S | Mass Spec | Environmental | MassBank | |
| 4-Chlorobenzenesulfonic acid | C6H5ClO3S | Mass Spec | Chemical | MassBank | |
| 4-Chlorobenzoate | C7H5ClO2 | Mass Spec | Chemical | MassBank | |
| 4-Chlorobenzophenone | C13H9ClO | Mass Spec | Environmental | MassBank | |
| 4-Chlorocatechol | C6H5ClO2 | Mass Spec | Metabolite | MassBank | |
| 4-Chlorophenol | C6H5ClO | Mass Spec | Environmental | MassBank | |
| 4-Chlorophenoxyacetic Acid | C8H7ClO3 | Mass Spec | Environmental | MassBank | |
| 4-Chlorophenylurea | C7H7ClN2O | Mass Spec | Chemical | MassBank | |
| 4-Chlorophthalic acid | C8H5ClO4 | Mass Spec | Chemical | MassBank | |
| 4-Chloropyridine 1-oxide | C5H4ClNO | Mass Spec | Chemical | MassBank | |
| 4-Chlororesorcinol | C6H5ClO2 | Mass Spec | Chemical | MassBank | |
| 4-Chlorosalicylic acid | C7H5ClO3 | Mass Spec | Pharmaceutical | MassBank | |
| 4-Chlorphenol | C6H5ClO | Mass Spec | Pharmaceutical | MassBank | |
| 4-Coumaric acid | C9H8O3 | Mass Spec | Chemical | MassBank | |
| 4-Coumaroylcholine | [C14H20NO3]+ | Mass Spec | Natural product | MassBank | |
| 4-Cyanobenzoic acid | C8H5NO2 | Mass Spec | Chemical | MassBank | |
| 4-Cyclododecyl-2,6-dimethylmorpholine | C18H35NO | Mass Spec | Environmental | MassBank | |
| 4-DECANOL | C10H22O | Mass Spec | Chemical | MassBank | |
| 4-DIACETYLAMINO-3-METHYLPHENYL ACETATE | C13H15NO4 | Mass Spec | Chemical | MassBank | |
| 4-DIMETHOXYMETHYL-3-PHENYL-5-OXOHEXANAL | C15H20O4 | Mass Spec | Chemical | MassBank | |
| 4-DIMETHYLAMINO-2(5H)-FURANONE | C6H9NO2 | Mass Spec | Chemical | MassBank | |
| 4-DIMETHYLAMINO-2-(3-FLUOROPHENYL)PYRIMIDINE | C12H12FN3 | Mass Spec | Chemical | MassBank | |
| 4-DIMETHYLAMINO-2-(4-FLUOROPHENYL)PYRIMIDINE | C12H12FN3 | Mass Spec | Chemical | MassBank | |
| 4-DIMETHYLAMINO-3-DIMETHYLAMINOMETHYL-2(5H)-FURANONE | C9H16N2O2 | Mass Spec | Chemical | MassBank | |
| 4-DIMETHYLAMINOBENZALDEHYDE | C9H11NO | Mass Spec | Chemical | MassBank | |
| 4-DIMETHYLAMINOBENZOIC ACID | C9H11NO2 | Mass Spec | Chemical | MassBank | |
| 4-DIMETHYLAMINOBENZOIC ACID METHYL ESTER | C10H13NO2 | Mass Spec | Chemical | MassBank | |
| 4-DIMETHYLAMINOPYRIDINE | C7H10N2 | Mass Spec | Chemical | MassBank | |
| 4-DIMETHYLAMINOPYRIDINE-N-OXIDE | C7H10N2O | Mass Spec | Chemical | MassBank | |
| 4-DODECYLOXY-2-HYDROXY-BENZOPHENONE | C25H34O3 | Mass Spec | Chemical | MassBank | |
| 4-Deoxyphloridzin | C21H24O9 | Mass Spec | Chemical | MassBank | |
| 4-Desmethyl-trimethoprim | C13H16N4O3 | Mass Spec | Pharmaceutical | MassBank | |
| 4-Desmethyltrimethoprim | C13H16N4O3 | Mass Spec | Environmental | MassBank | |
| 4-Dodecylbenzenesulfonic acid | C18H30O3S | Mass Spec | Chemical | MassBank | |
| 4-Dodecylmorpholine | C16H33NO | Mass Spec | Chemical | MassBank | |
| 4-Dodecylphenol | C18H30O | Mass Spec | Natural product | MassBank | |
| 4-ETHENYL-4-HYDROXY-2,2,6,6-TETRAMETHYLPIPERIDINE | C11H21NO | Mass Spec | Chemical | MassBank |