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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

(3AS,12bR)-5-Chloro-2-methyl-2,3,3a,12b-tetrahydro-1H-dibenzo[2,3:6,7]oxepino[4,5-c]pyrrole chemical structure

(3AS,12bR)-5-Chloro-2-methyl-2,3,3a,12b-tetrahydro-1H-dibenzo[2,3:6,7]oxepino[4,5-c]pyrrole

CAS: 1422571-39-8
Formula: C₁₇H₁₆ClNO
MW: 285.8 g/mol

VQ-043964

Reference Standard

(3AS,4R,6aR)-Tetrahydro-4-methoxyfuro[3,4-b]furan-2(3H)-one chemical structure

(3AS,4R,6aR)-Tetrahydro-4-methoxyfuro[3,4-b]furan-2(3H)-one

CAS: 866594-61-8
Formula: C₇H₁₀O₄
MW: 158.15 g/mol

VQ-025204

Reference Standard

(3AS,4R,6S,6aR)-6-Aminotetrahydro-2,2-dimethyl-4H-cyclopenta-1,3-dioxol-4-ol chemical structure

(3AS,4R,6S,6aR)-6-Aminotetrahydro-2,2-dimethyl-4H-cyclopenta-1,3-dioxol-4-ol

CAS: 592533-90-9
Formula: C₈H₁₅NO₃
MW: 173.21 g/mol

VQ-034236

Reference Standard

(3AS,4R,6S,6aR)-Methyl 4-((tert-butoxycarbonyl)amino)-3-(pentan-3-yl)-4,5,6,6a-tetrahydro-3aH-cyclopenta[d]isoxazole-6-carboxylate chemical structure

(3AS,4R,6S,6aR)-Methyl 4-((tert-butoxycarbonyl)amino)-3-(pentan-3-yl)-4,5,6,6a-tetrahydro-3aH-cyclopenta[d]isoxazole-6-carboxylate

CAS: 383910-25-6
Formula: C₁₈H₃₀N₂O₅
MW: 354.4 g/mol

VQ-043251

Reference Standard

(3AS,4S,6aR)-Tetrahydro-4-methoxyfuro[3,4-b]furan-2(3H)-one chemical structure

(3AS,4S,6aR)-Tetrahydro-4-methoxyfuro[3,4-b]furan-2(3H)-one

CAS: 866594-60-7
Formula: C₇H₁₀O₄
MW: 158.15 g/mol

VQ-030075

Reference Standard

(3AS,4S,6R,6aR)-4-(Iodomethyl)-6-methoxy-2,2-dimethyltetrahydrofuro[3,4-d][1,3]dioxole chemical structure

(3AS,4S,6R,6aR)-4-(Iodomethyl)-6-methoxy-2,2-dimethyltetrahydrofuro[3,4-d][1,3]dioxole

CAS: 38838-06-1
Formula: C₉H₁₅IO₄
MW: 314.12 g/mol

VQ-042518

Reference Standard

(3AS,4S,6R,6aR)-6-(N-Boc-amino)-3-(1-ethylpropyl)-3a,5,6,6a-tetrahydro-4H-cyclopent[d]isoxazole-4-carboxylic Acid Methyl Ester chemical structure

(3AS,4S,6R,6aR)-6-(N-Boc-amino)-3-(1-ethylpropyl)-3a,5,6,6a-tetrahydro-4H-cyclopent[d]isoxazole-4-carboxylic Acid Methyl Ester

CAS: 383910-22-3
Formula: C₁₈H₃₀N₂O₅
MW: 354.4 g/mol

VQ-033111

Reference Standard

(3BS,4aR)-3-(trifluoromethyl)-1,3b,4,4a-tetrahydrospiro[cyclopropa[3,4]cyclopenta[1,2-c]pyrazole-5,2'-[1,3]dithiolane]

(3BS,4aR)-3-(trifluoromethyl)-1,3b,4,4a-tetrahydrospiro[cyclopropa[3,4]cyclopenta[1,2-c]pyrazole-5,2'-[1,3]dithiolane]

CAS: 2375020-08-7
Formula: C₁₀H₉F₃N₂S₂
MW: 278.32 g/mol

VQ-037936

Reference Standard

(3E)-1-Acetyl-3-(ethoxyphenylmethylene)-2,3-dihydro-2-oxo-1H-indole-6-carboxylic Acid Methyl Ester chemical structure

(3E)-1-Acetyl-3-(ethoxyphenylmethylene)-2,3-dihydro-2-oxo-1H-indole-6-carboxylic Acid Methyl Ester

CAS: 1168152-06-4
Formula: C₂₁H₁₉NO₅
MW: 365.4 g/mol

VQ-032171

Reference Standard

(3R,3AR,6aS)-Hexahydrofuro[2,3-b]furan-3-yl 4-Nitrophenyl Ester Carbonic Acid chemical structure

(3R,3AR,6aS)-Hexahydrofuro[2,3-b]furan-3-yl 4-Nitrophenyl Ester Carbonic Acid

CAS: 252873-51-1
Formula: C₁₃H₁₃NO₇
MW: 295.24 g/mol

VQ-036575

Reference Standard

(3R,3AR,6S,6aS)-6-(Nitrooxy)hexahydrofuro[3,2-b]furan-3-yl Acetate chemical structure

(3R,3AR,6S,6aS)-6-(Nitrooxy)hexahydrofuro[3,2-b]furan-3-yl Acetate

CAS: 39698-15-2
Formula: C₈H₁₁NO₇
MW: 233.18 g/mol

VQ-044541

Reference Standard

(3R,3AS,6aR)-hexahydrofuro[2,3-b]furan-3-ol chemical structure

(3R,3AS,6aR)-hexahydrofuro[2,3-b]furan-3-ol

CAS: 156928-09-5
Formula: C₆H₁₀O₃
MW: 130.14 g/mol

VQ-030068

Reference Standard

(3R,3AS,6aR)-hexahydrofuro[2,3-b]furan-3-yl 4-nitrophenyl carbonate chemical structure

(3R,3AS,6aR)-hexahydrofuro[2,3-b]furan-3-yl 4-nitrophenyl carbonate

CAS: 192725-55-6
Formula: C₁₃H₁₃NO₇
MW: 295.24 g/mol

VQ-025208

Reference Standard

(3R,3AS,6aS)-6-Oxohexahydrofuro[3,2-b]furan-3-yl Nitrate chemical structure

(3R,3AS,6aS)-6-Oxohexahydrofuro[3,2-b]furan-3-yl Nitrate

CAS: 110627-22-0
Formula: C₆H₇NO₆
MW: 189.12 g/mol

VQ-043502

Reference Standard

(3R,4R,5R)-2-(4-Aminopyrrolo[2,1-f][1,2,4]triazin-7-yl)-3,4-bis(benzyloxy)-5-((benzyloxy)methyl)tetrahydrofuran-2-carbonitrile chemical structure

(3R,4R,5R)-2-(4-Aminopyrrolo[2,1-f][1,2,4]triazin-7-yl)-3,4-bis(benzyloxy)-5-((benzyloxy)methyl)tetrahydrofuran-2-carbonitrile

CAS: 1191237-68-9
Formula: C₃₃H₃₁N₅O₄
MW: 561.6 g/mol

VQ-044585

Reference Standard

(3R,4R,5R)-3,4-Bis(benzyloxy)-5-((benzyloxy)methyl)dihydrofuran-2(3H)-one chemical structure

(3R,4R,5R)-3,4-Bis(benzyloxy)-5-((benzyloxy)methyl)dihydrofuran-2(3H)-one

CAS: 55094-52-5
Formula: C₂₆H₂₆O₅
MW: 418.5 g/mol

VQ-043774

Reference Standard

(3R,4R,5R)-3,4-Dihydroxy-5-[(methylsulfonyl)oxy]-1-cyclohexene-1-carboxylic Acid Ethyl Ester chemical structure

(3R,4R,5R)-3,4-Dihydroxy-5-[(methylsulfonyl)oxy]-1-cyclohexene-1-carboxylic Acid Ethyl Ester

CAS: 220626-12-0
Formula: C₁₀H₁₆O₇S
MW: 280.3 g/mol

VQ-038807

Reference Standard

(3R,4R,5S)-4-(Acetylamino)-5-amino-3-(1-methylethoxy)-1-Cyclohexene-1-carboxylic Acid Ethyl Ester chemical structure

(3R,4R,5S)-4-(Acetylamino)-5-amino-3-(1-methylethoxy)-1-Cyclohexene-1-carboxylic Acid Ethyl Ester

CAS: 1052063-36-1
Formula: C₁₄H₂₄N₂O₄
MW: 284.35 g/mol

VQ-038801

Reference Standard

(3R,4R,5S)-Ethyl 4-acetamido-5-(diallylamino)-3-(pentan-3-yloxy)cyclohex-1-enecarboxylate chemical structure

(3R,4R,5S)-Ethyl 4-acetamido-5-(diallylamino)-3-(pentan-3-yloxy)cyclohex-1-enecarboxylate

CAS: 651324-09-3
Formula: C₂₂H₃₆N₂O₄
MW: 392.5 g/mol

VQ-038865

Reference Standard

(3R,4R)-4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidine-1-carbaldehyde chemical structure

(3R,4R)-4-Methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidine-1-carbaldehyde

CAS: 2227199-28-0
Formula: C₁₄H₁₉N₅O
MW: 273.33 g/mol

VQ-043917

Reference Standard

(3R,4R)-N-Methyl Paroxol chemical structure

(3R,4R)-N-Methyl Paroxol

CAS: 100332-12-5
Formula: C₁₃H₁₈FNO
MW: 223.29 g/mol

VQ-043250

Reference Standard

(3R,4R)-N,4-Dimethyl-1-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)piperidin-3-amine chemical structure

(3R,4R)-N,4-Dimethyl-1-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)piperidin-3-amine

CAS: 2097982-05-1
Formula: C₁₃H₁₉N₅
MW: 245.32 g/mol

VQ-044085

Reference Standard

(3R,4S,5S,6R,7R,9R,11R,12R,13S,14R)-14-Ethyl-4,6,12,13-tetrahydroxy-7-methoxy-3,5,7,9,11,13-hexamethyloxacyclotetradecane-2,10-dione chemical structure

(3R,4S,5S,6R,7R,9R,11R,12R,13S,14R)-14-Ethyl-4,6,12,13-tetrahydroxy-7-methoxy-3,5,7,9,11,13-hexamethyloxacyclotetradecane-2,10-dione

CAS: 2376120-29-3
Formula: C₂₂H₄₀O₈
MW: 432.5 g/mol

VQ-036354

Reference Standard

(3R,4S,6R)-6-Methoxytetrahydro-2H-pyran-3,4-diyl bis(4-methylbenzoate) chemical structure

(3R,4S,6R)-6-Methoxytetrahydro-2H-pyran-3,4-diyl bis(4-methylbenzoate)

CAS: 78185-67-8
Formula: C₂₂H₂₄O₆
MW: 384.4 g/mol

VQ-044073

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