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-Hydroxybenzoate | C7H6O3 | Mass Spec | Chemical | MassBank | |
| 4-Hydroxybenzoic acid | C7H6O3 | Mass Spec | Chemical | MassBank | |
| 4-Hydroxybenzonitrile | C7H5NO | Mass Spec | Chemical | MassBank | |
| 4-Hydroxybenzotriazole | C6H5N3O | Mass Spec | Environmental | MassBank | |
| 4-Hydroxybenzoylcholine | [C12H18NO3]+ | Mass Spec | Natural product | MassBank | |
| 4-Hydroxybenzyl alcohol | C7H8O2 | Mass Spec | Natural product | MassBank | |
| 4-Hydroxycoumarin | C9H6O3 | Mass Spec | Environmental | MassBank | |
| 4-Hydroxydiphenylamine | C12H11NO | Mass Spec | Pesticide | MassBank | |
| 4-Hydroxylutein | C40H56O3 | Mass Spec | Natural product | MassBank | |
| 4-Hydroxymandelate | C8H8O4 | Mass Spec | Chemical | MassBank | |
| 4-Hydroxymethylimidazole | C4H6N2O | Mass Spec | Chemical | MassBank | |
| 4-Hydroxymyxol | C40H56O4 | Mass Spec | Chemical | MassBank | |
| 4-Hydroxyphenethyl alcohol | C8H10O2 | Mass Spec | Natural product | MassBank | |
| 4-Hydroxyphenyl benzoate | C13H10O3 | Mass Spec | Chemical | MassBank | |
| 4-Hydroxyphenylacetic acid | C8H8O3 | Mass Spec | Natural product | MassBank | |
| 4-Hydroxyphenylpyruvate | C9H8O4 | Mass Spec | Natural product | MassBank | |
| 4-Hydroxyphenylpyruvic acid | C9H8O4 | Mass Spec | Natural product | MassBank | |
| 4-Hydroxypropanolol-sulfate | C16H21NO6S | Mass Spec | Environmental | MassBank | |
| 4-Hydroxypyridine | C5H5NO | Mass Spec | Natural product | MassBank | |
| 4-Hydroxyquinoline | C9H7NO | Mass Spec | Environmental | MassBank | |
| 4-Hydroxytamoxifen | C26H29NO2 | Mass Spec | Environmental | MassBank | |
| 4-Hydroxytrimethoprim | C14H18N4O4 | Mass Spec | Pharmaceutical | MassBank | |
| 4-IMIDAZOLEACETIC ACID | C5H6N2O2 | Mass Spec | Natural product | MassBank | |
| 4-IODO-3,5-DIMETHYLISOXAZOLE | C5H6INO | Mass Spec | Chemical | MassBank | |
| 4-IODOBENZOIC ACID | C7H5IO2 | Mass Spec | Chemical | MassBank | |
| 4-IODONITROBENZENE | C6H4INO2 | Mass Spec | Chemical | MassBank | |
| 4-ISOPROPENYLBICYCLO(3.2.2)NONA-3,6-DIEN-2-ONE | C12H14O | Mass Spec | Chemical | MassBank | |
| 4-ISOPROPYL-2-CYCLOHEXENONE | C9H14O | Mass Spec | Chemical | MassBank | |
| 4-ISOPROPYL-2-METHYL-1,2,3,3A,6,6A-HEXAHYDROPYRROLO(3,4-C)PYRROLE-1,3-DIONE | C10H14N2O2 | Mass Spec | Chemical | MassBank | |
| 4-ISOPROPYL-3-METHYLENE-1-OXA-3,3A,4,5,6,7,8,8A-OCTAHYDROAZULEN-2(1H)-ONE | C13H20O2 | Mass Spec | Chemical | MassBank | |
| 4-ISOPROPYL-6-METHYLENE-3,4,4A,5,6,7,8,8A-OCTAHYDRO-1(2H)-NAPHTHALENONE | C14H22O | Mass Spec | Chemical | MassBank | |
| 4-ISOPROPYL-6-TRIMETHYLSILYLMETHYL-3,4,4A,5,8,8A-HEXAHYDRO-1(2H)-NAPHTHALENONE | C17H30OSi | Mass Spec | Chemical | MassBank | |
| 4-ISOPROPYL-7-TRIMETHYLSILYLMETHYL-3,4,4A,5,8,8A-HEXAHYDRO-1(2H)-NAPHTHALENONE | C17H30OSi | Mass Spec | Chemical | MassBank | |
| 4-ISOPROPYLBENZALDEHYDE | C10H12O | Mass Spec | Chemical | MassBank | |
| 4-ISOPROPYLBENZYL BENZOATE | C17H18O2 | Mass Spec | Chemical | MassBank | |
| 4-ISOPROPYLBICYCLO(3.2.2)NONA-3,6-DIEN-2-ONE | C12H16O | Mass Spec | Chemical | MassBank | |
| 4-ISOPROPYLCYCLOHEXANOL | C9H18O | Mass Spec | Chemical | MassBank | |
| 4-ISOPROPYLPHENYL METHYL KETONE | C11H14O | Mass Spec | Chemical | MassBank | |
| 4-ISOPROPYLPYRIDINE | C8H11N | Mass Spec | Chemical | MassBank | |
| 4-Iodophenol | C6H5IO | Mass Spec | Chemical | MassBank | |
| 4-Iodphenol | C6H5IO | Mass Spec | Environmental | MassBank | |
| 4-Isopropylaniline | C9H13N | Mass Spec | Environmental | MassBank | |
| 4-Isopropylantipyrine | C14H18N2O | Mass Spec | Environmental | MassBank | |
| 4-Isopropylbenzenesulfonic acid | C9H12O3S | Mass Spec | Chemical | MassBank | |
| 4-Isopropylbenzyl alcohol | C10H14O | Mass Spec | Chemical | MassBank | |
| 4-Isopropylphenol | C9H12O | Mass Spec | Chemical | MassBank | |
| 4-Keto-4'-hydroxy-diatoxanthin | C40H52O4 | Mass Spec | Natural product | MassBank | |
| 4-Keto-deepoxyneoxanthin | C40H54O4 | Mass Spec | Natural product | MassBank | |
| 4-Ketoalloxanthin | C40H50O3 | Mass Spec | Natural product | MassBank | |
| 4-Ketozeinoxanthin | C40H54O2 | Mass Spec | Natural product | MassBank |