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-Methylumbelliferylglucuronide | C16H16O9 | Mass Spec | Natural product | MassBank | |
| 4-Methylvaleric acid | C6H12O2 | Mass Spec | Chemical | MassBank | |
| 4-N,N-BIS(TRIMETHYLSILYL)ANISIDINE | C13H25NOSi2 | Mass Spec | Chemical | MassBank | |
| 4-N-AMYLBENZOIC ACID METHYL ESTER | C13H18O2 | Mass Spec | Chemical | MassBank | |
| 4-N-BUTYLBENZOIC ACID METHYL ESTER | C12H16O2 | Mass Spec | Chemical | MassBank | |
| 4-N-HYDROXYIMINOMETHYL-2,5-DIMETHOXY-6-METHYLTROPONE | C11H13NO4 | Mass Spec | Chemical | MassBank | |
| 4-NITROANILINE | C6H6N2O2 | Mass Spec | Chemical | MassBank | |
| 4-NITROANISOL | C7H7NO3 | Mass Spec | Chemical | MassBank | |
| 4-NITROBENZALDEHYDE | C7H5NO3 | Mass Spec | Chemical | MassBank | |
| 4-NITROBENZOIC ACID CYCLOHEXYL ESTER | C13H15NO4 | Mass Spec | Chemical | MassBank | |
| 4-NITROBENZONITRILE | C7H4N2O2 | Mass Spec | Chemical | MassBank | |
| 4-NITROBENZYL ALCOHOL | C7H7NO3 | Mass Spec | Chemical | MassBank | |
| 4-NITROBENZYL BENZOATE | C14H11NO4 | Mass Spec | Chemical | MassBank | |
| 4-NITROBENZYL BROMIDE | C7H6BrNO2 | Mass Spec | Chemical | MassBank | |
| 4-NITROBENZYLALCOHOL | C7H7NO3 | Mass Spec | Chemical | MassBank | |
| 4-NITROPHENOXYACETIC ACID METHYL ESTER | C9H9NO5 | Mass Spec | Chemical | MassBank | |
| 4-NITROPHENOXYACETIC ACID TRIMETHYLSILYL ESTER | C11H15NO5Si | Mass Spec | Chemical | MassBank | |
| 4-NITROPHENYL ACETATE | C8H7NO4 | Mass Spec | Chemical | MassBank | |
| 4-NITROPHENYL PENTAFLUOROBENZYL ETHER | C13H6F5NO3 | Mass Spec | Chemical | MassBank | |
| 4-NITROPHENYLACETIC ACID | C8H7NO4 | Mass Spec | Chemical | MassBank | |
| 4-NITROPHENYLACETIC ACID METHYL ESTER | C9H9NO4 | Mass Spec | Chemical | MassBank | |
| 4-NITROPHENYLACETIC ACID TRIMETHYLSILYL ESTER | C11H15NO4Si | Mass Spec | Chemical | MassBank | |
| 4-NITROPHENYLACETONITRILE | C8H6N2O2 | Mass Spec | Chemical | MassBank | |
| 4-NITROPHENYLHYDRAZINE | C6H7N3O2 | Mass Spec | Chemical | MassBank | |
| 4-NITROPYRIDINE-N-OXIDE | C5H4N2O3 | Mass Spec | Chemical | MassBank | |
| 4-NITROQUINOLINE-N-OXIDE | C9H6N2O3 | Mass Spec | Chemical | MassBank | |
| 4-NITROSOMETHYL-6-TRIFLUOROMETHYL-1,2-DIHYDROPYRIMIDIN-2-ONE | C6H4F3N3O2 | Mass Spec | Chemical | MassBank | |
| 4-NITROTOLUENE | C7H7NO2 | Mass Spec | Chemical | MassBank | |
| 4-NONANONE | C9H18O | Mass Spec | Chemical | MassBank | |
| 4-Nitro-1,2-phenylenediamine | C6H7N3O2 | Mass Spec | Chemical | MassBank | |
| 4-Nitro-N-phenylaniline | C12H10N2O2 | Mass Spec | Chemical | MassBank | |
| 4-Nitroanisole | C7H7NO3 | Mass Spec | Natural product | MassBank | |
| 4-Nitroanthranilic acid | C7H6N2O4 | Mass Spec | Chemical | MassBank | |
| 4-Nitrobenzoic acid | C7H5NO4 | Mass Spec | Chemical | MassBank | |
| 4-Nitrobenzyltriphenylphosphonium | [C25H21NO2P]+ | Mass Spec | Chemical | MassBank | |
| 4-Nitrophenol | C6H5NO3 | Mass Spec | Environmental | MassBank | |
| 4-Nitrophenyl phosphate | C6H6NO6P | Mass Spec | Chemical | MassBank | |
| 4-Nitroquinoline-1-oxide | C9H6N2O3 | Mass Spec | Environmental | MassBank | |
| 4-Nitrosodiphenylamine | C12H10N2O | Mass Spec | Chemical | MassBank | |
| 4-Nonylphenol-branched | C15H24O | Mass Spec | Natural product | MassBank | |
| 4-O-ACETYL-1,3,5,6-TETRA-O-METHYL-2-N-METHYLACETAMIDO-2-DEOXYHEXITOL | C15H29NO7 | Mass Spec | Chemical | MassBank | |
| 4-O-Caffeoylquinic acid | C16H18O9 | Mass Spec | Natural product | MassBank | |
| 4-O-Feruloylquinic acid | C17H20O9 | Mass Spec | Natural product | MassBank | |
| 4-OCTYLANILINE | C14H23N | Mass Spec | Chemical | MassBank | |
| 4-OCTYLBENZOIC ACID METHYL ESTER | C16H24O2 | Mass Spec | Chemical | MassBank | |
| 4-OCTYLBENZOIC ACID TRIMETHYLSILYL ESTER | C18H30O2Si | Mass Spec | Chemical | MassBank | |
| 4-OCTYLCYCLOHEXANONE | C14H26O | Mass Spec | Chemical | MassBank | |
| 4-OCTYLOXYBENZOIC ACID METHYL ESTER | C16H24O3 | Mass Spec | Chemical | MassBank | |
| 4-OCTYLOXYBENZOIC ACID TRIMETHYLSILYL ESTER | C18H30O3Si | Mass Spec | Chemical | MassBank | |
| 4-OXO-1,6,7,8,9,9A-HEXAHYDRO-4H-PYRIDO(1,2-A)PYRIMIDINE-3-CARBOXYLIC ACID ETHYL ESTER | C11H16N2O3 | Mass Spec | Chemical | MassBank |