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-Fluoro-3-nitroaniline | C6H5FN2O2 | Mass Spec | Chemical | MassBank | |
| 4-Fluoroaniline | C6H6FN | Mass Spec | Chemical | MassBank | |
| 4-Fluorobenzoate | C7H5FO2 | Mass Spec | Chemical | MassBank | |
| 4-Fluorobenzoylpropionic acid | C10H9FO3 | Mass Spec | Environmental | MassBank | |
| 4-Formyl-antipyrine | C12H12N2O2 | Mass Spec | Environmental | MassBank | |
| 4-Formylaminoantipyrine | C12H13N3O2 | Mass Spec | Environmental | MassBank | |
| 4-GlcNAc3Man3GlcNAc2 | C58H97N5O41 | Mass Spec | Natural product | MassBank | |
| 4-HDoHE | C22H32O3 | Mass Spec | Lipid | MassBank | |
| 4-HEPTANONE | C7H14O | Mass Spec | Chemical | MassBank | |
| 4-HEXYLRESORCINOL | C12H18O2 | Mass Spec | Chemical | MassBank | |
| 4-HIDROXY-7-CHLORO BENZOPYLIMIDINE | C8H5ClN2O | Mass Spec | Chemical | MassBank | |
| 4-HYDROXY-2-BUTANONE | C4H8O2 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXY-3,3',4',7-TETRAMETHOXYFLAVAN | C19H22O6 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXY-3-(3-OXO-1-PHENYLBUTYL)-2H-CHROMEN-2-ONE | C19H16O4 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXY-3-HEXANONE | C6H12O2 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXY-3-METHOXYBENZALDEHYDE | C8H8O3 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXY-3-METHOXYBENZOIC ACID | C8H8O4 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXY-3-METHOXYBENZOIC ACID METHYL ESTER | C9H10O4 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXY-3-METHOXYCINNAMIC ACID | C10H10O4 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXY-3-METHOXYMANDELIC ACID-TRI-TMS | C18H34O5Si3 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXY-3-METHOXYPHENYLACETIC ACID (2,5,6-D3,ALPHA,ALPHA-D2) | C9H10O4 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXY-5,8-DIMETHYL-5-PROPYL-1,7-NONADIENE | C14H26O | Mass Spec | Chemical | MassBank | |
| 4-HYDROXY-7-METHOXY-3-METHYLCOUMARINE | C11H10O4 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXY-7-METHOXY-3-PHENYLCHROMAN (4D) | C16H16O3 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXY-N,N-DIMETHYLTRYPTAMINE PSILOCIN | C12H16N2O | Mass Spec | Chemical | MassBank | |
| 4-HYDROXY4-METHYLCYCLOHEXA-2,5-DIEN-1-ONE | C7H8O2 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXYACETANILIDE | C8H9NO2 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXYBENZOIC ACID METHYL ESTER | C8H8O3 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXYBENZOPHENONE | C13H10O2 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXYBIPHENYL | C12H10O | Mass Spec | Chemical | MassBank | |
| 4-HYDROXYDIPHENYL | C12H10O | Mass Spec | Chemical | MassBank | |
| 4-HYDROXYISONICOTINIC ACID | C6H5NO3 | Mass Spec | Chemical | MassBank | |
| 4-HYDROXYTROPOLONE | C7H6O3 | Mass Spec | Chemical | MassBank | |
| 4-Hexylaniline | C12H19N | Mass Spec | Chemical | MassBank | |
| 4-Hexyloxyaniline | C12H19NO | Mass Spec | Chemical | MassBank | |
| 4-Hydroxy-1-(2-hydroxyethyl)-2,2,6,6-tetramethylpiperidine | C11H23NO2 | Mass Spec | Environmental | MassBank | |
| 4-Hydroxy-1H-benzotriazole | C6H5N3O | Mass Spec | Metabolite | MassBank | |
| 4-Hydroxy-2',4',6'-trimethoxychalcone (Flavokawain A?) | C18H18O5 | Mass Spec | Natural product | MassBank | |
| 4-Hydroxy-2,2,6,6-tetramethylpiperidin-1-yl)oxidanyl | C9H19NO2 | Mass Spec | Chemical | MassBank | |
| 4-Hydroxy-3-methoxybenzoate | C8H8O4 | Mass Spec | Chemical | MassBank | |
| 4-Hydroxy-3-methoxycinnamaldehyde | C10H10O3 | Mass Spec | Chemical | MassBank | |
| 4-Hydroxy-3-methoxymandelate | C9H10O5 | Mass Spec | Chemical | MassBank | |
| 4-Hydroxy-3-methoxypyridine | C6H7NO2 | Mass Spec | Chemical | MassBank | |
| 4-Hydroxy-3-nitrophenylarsonic acid | C6H6AsNO6 | Mass Spec | Environmental | MassBank | |
| 4-Hydroxy-L-proline | C5H9NO3 | Mass Spec | Natural product | MassBank | |
| 4-HydroxyMandelic acid | C8H8O4 | Mass Spec | Natural product | MassBank | |
| 4-Hydroxyacetophenone | C8H8O2 | Mass Spec | Chemical | MassBank | |
| 4-Hydroxyamphetamine | C9H13NO | Mass Spec | Chemical | MassBank | |
| 4-Hydroxybenzaldehyde | C7H6O2 | Mass Spec | Environmental | MassBank | |
| 4-Hydroxybenzenesulfonic acid | C6H6O4S | Mass Spec | Environmental | MassBank |