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Impurities & Reference Standards

API Impurities

Source 1942 api impurities for research, QC and production, documented with COA and SDS.

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Reference Standard

tert-Butyl (S)-2-(4-fluoro-3,5-dimethylphenyl)-4-methyl-3-(2-oxo-2,3-dihydro-1H-imidazol-1-yl)-2,4,6,7-tetrahydro-5H-pyrazolo[4,3-c]pyridine-5-carboxylate chemical structure

tert-Butyl (S)-2-(4-fluoro-3,5-dimethylphenyl)-4-methyl-3-(2-oxo-2,3-dihydro-1H-imidazol-1-yl)-2,4,6,7-tetrahydro-5H-pyrazolo[4,3-c]pyridine-5-carboxylate

CAS: 2212021-61-7
Formula: C₂₃H₂₈FN₅O₃
MW: 441.5 g/mol

VQ-040520

Reference Standard

tert-Butyl (S)-2-(5-bromo-1H-imidazol-2-yl)pyrrolidine-1-carboxylate chemical structure

tert-Butyl (S)-2-(5-bromo-1H-imidazol-2-yl)pyrrolidine-1-carboxylate

CAS: 1007882-59-8
Formula: C₁₂H₁₈BrN₃O₂
MW: 316.19 g/mol

VQ-048812

Reference Standard

tert-Butyl (S)-3-(3-(2,2-dimethoxyethyl)ureido)-2-(4-fluoro-3,5-dimethylphenyl)-4-methyl-2,4,6,7-tetrahydro-5H-pyrazolo[4,3-c]pyridine-5-carboxylate chemical structure

tert-Butyl (S)-3-(3-(2,2-dimethoxyethyl)ureido)-2-(4-fluoro-3,5-dimethylphenyl)-4-methyl-2,4,6,7-tetrahydro-5H-pyrazolo[4,3-c]pyridine-5-carboxylate

CAS: 2212021-60-6
Formula: C₂₅H₃₆FN₅O₅
MW: 505.6 g/mol

VQ-038785

Reference Standard

tert-Butyl (S)-3-(4-(7-carbamoyl-2H-indazol-2-yl)phenyl)piperidine-1-carboxylate chemical structure

tert-Butyl (S)-3-(4-(7-carbamoyl-2H-indazol-2-yl)phenyl)piperidine-1-carboxylate

CAS: 1038916-11-8
Formula: C₂₄H₂₈N₄O₃
MW: 420.5 g/mol

VQ-023268

Reference Standard

tert-Butyl (S)-3-(4-(7-cyano-2H-indazol-2-yl)phenyl)piperidine-1-carboxylate

tert-Butyl (S)-3-(4-(7-cyano-2H-indazol-2-yl)phenyl)piperidine-1-carboxylate

CAS: 1476776-81-4
Formula: C₂₄H₂₆N₄O₂
MW: 402.49 g/mol

VQ-038657

Reference Standard

tert-Butyl (S)-3-amino-2-(4-fluoro-3,5-dimethylphenyl)-4-methyl-2,4,6,7-tetrahydro-5H-pyrazolo[4,3-c]pyridine-5-carboxylate chemical structure

tert-Butyl (S)-3-amino-2-(4-fluoro-3,5-dimethylphenyl)-4-methyl-2,4,6,7-tetrahydro-5H-pyrazolo[4,3-c]pyridine-5-carboxylate

CAS: 2212021-59-3
Formula: C₂₀H₂₇FN₄O₂
MW: 374.5 g/mol

VQ-038784

Reference Standard

tert-Butyl (S)-4-((4-fluoroisoquinolin-5-yl)sulfonyl)-3-methyl-1,4-diazepane-1-carboxylate chemical structure

tert-Butyl (S)-4-((4-fluoroisoquinolin-5-yl)sulfonyl)-3-methyl-1,4-diazepane-1-carboxylate

CAS: 1360538-86-8
Formula: C₂₀H₂₆FN₃O₄S
MW: 423.5 g/mol

VQ-033561

Reference Standard

tert-Butyl (S)-6-((1-(benzyloxy)-3-(3-(methylsulfonyl)phenyl)-1-oxopropan-2-yl)carbamoyl)-5,7-dichloro-3,4-dihydroisoquinoline-2(1H)-carboxylate chemical structure

tert-Butyl (S)-6-((1-(benzyloxy)-3-(3-(methylsulfonyl)phenyl)-1-oxopropan-2-yl)carbamoyl)-5,7-dichloro-3,4-dihydroisoquinoline-2(1H)-carboxylate

CAS: 1194550-61-2
Formula: C₃₂H₃₄Cl₂N₂O₇S
MW: 661.6 g/mol

VQ-038035

Reference Standard

tert-Butyl (trans-4-(2-oxoethyl)cyclohexyl)carbamate chemical structure

tert-Butyl (trans-4-(2-oxoethyl)cyclohexyl)carbamate

CAS: 215790-29-7
Formula: C₁₃H₂₃NO₃
MW: 241.33 g/mol

VQ-024804

Reference Standard

tert-Butyl (Z)-2-((2-methoxy-2-oxoethoxy)imino)-3-oxobutanoate chemical structure

tert-Butyl (Z)-2-((2-methoxy-2-oxoethoxy)imino)-3-oxobutanoate

CAS: 84080-68-2
Formula: C₁₁H₁₇NO₆
MW: 259.26 g/mol

VQ-024844

Reference Standard

Tert-Butyl [(1R,5S,6S)-6-(aminomethyl)-3-ethylbicyclo[3.2.0]hept-3-en-6-yl]acetate chemical structure

Tert-Butyl [(1R,5S,6S)-6-(aminomethyl)-3-ethylbicyclo[3.2.0]hept-3-en-6-yl]acetate

CAS: 1138245-20-1
Formula: C₁₆H₂₇NO₂
MW: 265.39 g/mol

VQ-026726

Reference Standard

tert-Butyl [(4R,6S)-6-(chloromethyl)-2,2-dimethyl-1,3-dioxan-4-yl]acetate chemical structure

tert-Butyl [(4R,6S)-6-(chloromethyl)-2,2-dimethyl-1,3-dioxan-4-yl]acetate

CAS: 154026-94-5
Formula: C₁₃H₂₃ClO₄
MW: 278.77 g/mol

VQ-023512

Reference Standard

tert-Butyl [cis-4-(2-oxoethyl)cyclohexyl]carbamate chemical structure

tert-Butyl [cis-4-(2-oxoethyl)cyclohexyl]carbamate

CAS: 847417-37-2
Formula: C₁₃H₂₃NO₃
MW: 241.33 g/mol

VQ-029657

Reference Standard

tert-Butyl 2-((1R,5S,6R)-6-(aminomethyl)-3-ethylbicyclo[3.2.0]hept-3-en-6-yl)acetate chemical structure

tert-Butyl 2-((1R,5S,6R)-6-(aminomethyl)-3-ethylbicyclo[3.2.0]hept-3-en-6-yl)acetate

CAS: 1415817-44-5
Formula: C₁₆H₂₇NO₂
MW: 265.39 g/mol

VQ-031950

Reference Standard

tert-Butyl 2-((1R,5S,6S)-3-ethyl-6-(nitromethyl)bicyclo[3.2.0]hept-3-en-6-yl)acetate chemical structure

tert-Butyl 2-((1R,5S,6S)-3-ethyl-6-(nitromethyl)bicyclo[3.2.0]hept-3-en-6-yl)acetate

CAS: 1138246-18-0
Formula: C₁₆H₂₅NO₄
MW: 295.37 g/mol

VQ-031948

Reference Standard

tert-Butyl 2-((1R,5S)-3-ethylbicyclo[3.2.0]hept-3-en-6-ylidene)acetate chemical structure

tert-Butyl 2-((1R,5S)-3-ethylbicyclo[3.2.0]hept-3-en-6-ylidene)acetate

CAS: 1469800-26-7
Formula: C₁₅H₂₂O₂
MW: 234.33 g/mol

VQ-049137

Reference Standard

tert-Butyl 2-((4R,6R)-6-((E)-2-(4-(4-fluorophenyl)-6-isopropyl-2-(N-methylmethylsulfonamido)pyrimidin-5-yl)vinyl)-2,2-dimethyl-1,3-dioxan-4-yl)acetate chemical structure

tert-Butyl 2-((4R,6R)-6-((E)-2-(4-(4-fluorophenyl)-6-isopropyl-2-(N-methylmethylsulfonamido)pyrimidin-5-yl)vinyl)-2,2-dimethyl-1,3-dioxan-4-yl)acetate

CAS: 2758676-77-4
Formula: C₂₉H₄₀FN₃O₆S
MW: 577.7 g/mol

VQ-027907

Reference Standard

tert-Butyl 2-((4R,6R)-6-(chloromethyl)-2,2-dimethyl-1.3-dioxan-4-yl)acetate chemical structure

tert-Butyl 2-((4R,6R)-6-(chloromethyl)-2,2-dimethyl-1.3-dioxan-4-yl)acetate

CAS: 521974-01-6
Formula: C₁₃H₂₃ClO₄
MW: 278.77 g/mol

VQ-033673

Reference Standard

tert-Butyl 2-((4R,6R)-6-formyl-2,2-dimethyl-1,3-dioxan-4-yl)acetate chemical structure

tert-Butyl 2-((4R,6R)-6-formyl-2,2-dimethyl-1,3-dioxan-4-yl)acetate

CAS: 2124275-54-1
Formula: C₁₃H₂₂O₅
MW: 258.31 g/mol

VQ-027909

Reference Standard

tert-Butyl 2-((4S,6R)-6-(chloromethyl)-2,2-dimethyl-1,3-dioxan-4-yl)acetate chemical structure

tert-Butyl 2-((4S,6R)-6-(chloromethyl)-2,2-dimethyl-1,3-dioxan-4-yl)acetate

CAS: 521973-99-9
Formula: C₁₃H₂₃ClO₄
MW: 278.77 g/mol

VQ-026528

Reference Standard

tert-Butyl 2-((4S,6S)-6-((E)-2-(4-(4-fluorophenyl)-6-isopropyl-2-(N-methylmethylsulfonamido)pyrimidin-5-yl)vinyl)-2,2-dimethyl-1,3-dioxan-4-yl)acetate chemical structure

tert-Butyl 2-((4S,6S)-6-((E)-2-(4-(4-fluorophenyl)-6-isopropyl-2-(N-methylmethylsulfonamido)pyrimidin-5-yl)vinyl)-2,2-dimethyl-1,3-dioxan-4-yl)acetate

CAS: 1378943-63-5
Formula: C₂₉H₄₀FN₃O₆S
MW: 577.7 g/mol

VQ-028848

Reference Standard

tert-Butyl 2-((4S,6S)-6-(chloromethyl(02,2-1,3-dioxan-4-yl)acetate chemical structure

tert-Butyl 2-((4S,6S)-6-(chloromethyl(02,2-1,3-dioxan-4-yl)acetate

CAS: 521974-00-5
Formula: C₁₃H₂₃ClO₄
MW: 278.77 g/mol

VQ-027914

Reference Standard

tert-Butyl 2-((5,6-diphenylpyrazin-2-yl)oxy)acetate chemical structure

tert-Butyl 2-((5,6-diphenylpyrazin-2-yl)oxy)acetate

CAS: 162928-03-2
Formula: C₂₂H₂₂N₂O₃
MW: 362.4 g/mol

VQ-033802

Reference Standard

tert-Butyl 2-(2,2-dimethyl-4H-1,3-benzodioxin-6-yl)-2-oxoethylcarbamate chemical structure

tert-Butyl 2-(2,2-dimethyl-4H-1,3-benzodioxin-6-yl)-2-oxoethylcarbamate

CAS: 452339-71-8
Formula: C₁₇H₂₃NO₅
MW: 321.4 g/mol

VQ-042878

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