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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

1,1,3,3-Tetramethyldisiloxane-1,3-diol chemical structure

1,1,3,3-Tetramethyldisiloxane-1,3-diol

CAS: 1118-15-6
Formula: C₄H₁₄O₃Si₂
MW: 166.32 g/mol

VQ-033858

Reference Standard

1,1,3,3,5,5-Hexamethyltrisiloxane-1,5-diol chemical structure

1,1,3,3,5,5-Hexamethyltrisiloxane-1,5-diol

CAS: 3663-50-1
Formula: C₆H₂₀O₄Si₃
MW: 240.48 g/mol

VQ-042179

Reference Standard

1,1,5,5-Tetramethyl-2-(1-methylethenyl)cyclohexane chemical structure

1,1,5,5-Tetramethyl-2-(1-methylethenyl)cyclohexane

CAS: 63251-38-7
Formula: C₁₃H₂₄
MW: 180.33 g/mol

VQ-032756

Reference Standard

1,1'-((Methylenebis(sulfanediyl))bis(ethane-2,1-diyl))bis(3-cyano-3-methylguanidine) chemical structure

1,1'-((Methylenebis(sulfanediyl))bis(ethane-2,1-diyl))bis(3-cyano-3-methylguanidine)

CAS: 208447-53-4
Formula: C₁₁H₂₀N₈S₂
MW: 328.5 g/mol

VQ-045042

Reference Standard

1,1'-((Propane-1,3-diylbis(oxy))bis(3-methoxy-4,1-phenylene))bis(ethan-1-one) chemical structure

1,1'-((Propane-1,3-diylbis(oxy))bis(3-methoxy-4,1-phenylene))bis(ethan-1-one)

CAS: 19417-90-4
Formula: C₂₁H₂₄O₆
MW: 372.4 g/mol

VQ-037664

Reference Standard

1,1'-(1,4-Phenylene)bis(5-methylpyridin-2(1H)-one) chemical structure

1,1'-(1,4-Phenylene)bis(5-methylpyridin-2(1H)-one)

CAS: 2251047-36-4
Formula: C₁₈H₁₆N₂O₂
MW: 292.3 g/mol

VQ-033126

Reference Standard

1,1'-(1,4,8,11-Tetraazacyclotetradecane-1,8-diyl)bis(2,2,2-trifluoroethan-1-one) chemical structure

1,1'-(1,4,8,11-Tetraazacyclotetradecane-1,8-diyl)bis(2,2,2-trifluoroethan-1-one)

CAS: 548488-50-2
Formula: C₁₄H₂₂F₆N₄O₂
MW: 392.34 g/mol

VQ-033238

Reference Standard

1,1'-(10,11-Dihydro-5H-Dibenzo[b,f]azepine-3,5-diyl)bis(ethan-1-one)

1,1'-(10,11-Dihydro-5H-Dibenzo[b,f]azepine-3,5-diyl)bis(ethan-1-one)

CAS: 40583-97-9
Formula: C₁₈H₁₇NO₂
MW: 279.33 g/mol

VQ-044326

Reference Standard

1,1'-(3-Methylthiophene-2,5-diyl)bis(ethan-1-one)

1,1'-(3-Methylthiophene-2,5-diyl)bis(ethan-1-one)

CAS: 1303946-86-2
Formula: C₉H₁₀O₂S
MW: 182.24 g/mol

VQ-048960

Reference Standard

1,1'-(Oxybis(propane-3,1-diyl))dipiperidine chemical structure

1,1'-(Oxybis(propane-3,1-diyl))dipiperidine

CAS: 110129-10-7
Formula: C₁₆H₃₂N₂O
MW: 268.44 g/mol

VQ-041538

Reference Standard

1,1'-[[[[(4-Chlorophenyl)carbamimidoyl]imino]methylene]bis[imino(hexane-1,6-diyl)]]bis[5-(4-chlorophenyl)biguanide] chemical structure

1,1'-[[[[(4-Chlorophenyl)carbamimidoyl]imino]methylene]bis[imino(hexane-1,6-diyl)]]bis[5-(4-chlorophenyl)biguanide]

CAS: 2734290-31-2
Formula: C₃₆H₅₀Cl₃N₁₅
MW: 799.2 g/mol

VQ-029742

Reference Standard

1,1'-[Dithiobis(methylene)]biscyclopropaneacetic Acid chemical structure

1,1'-[Dithiobis(methylene)]biscyclopropaneacetic Acid

CAS: 162515-67-5
Formula: C₁₂H₁₈O₄S₂
MW: 290.4 g/mol

VQ-026771

Reference Standard

1,1'-[Dithiobis(methylene)]biscyclopropaneacetic Acid Methyl Ester chemical structure

1,1'-[Dithiobis(methylene)]biscyclopropaneacetic Acid Methyl Ester

CAS: 1446481-28-2
Formula: C₁₃H₂₀O₄S₂
MW: 304.4 g/mol

VQ-031994

Reference Standard

1,1'-Biphenyl-2-ylcarbamic acid chemical structure

1,1'-Biphenyl-2-ylcarbamic acid

CAS: 50443-60-2
Formula: C₁₃H₁₁NO₂
MW: 213.23 g/mol

VQ-035198

Reference Standard

1,1',1'',1'''-(1,4,8,11-Tetraazacyclotetradecane-1,4,8,11-tetrayl)tetrakis(2,2,2-trifluoroethan-1-one) chemical structure

1,1',1'',1'''-(1,4,8,11-Tetraazacyclotetradecane-1,4,8,11-tetrayl)tetrakis(2,2,2-trifluoroethan-1-one)

CAS: 201610-16-4
Formula: C₁₈H₂₀F₁₂N₄O₄
MW: 584.4 g/mol

VQ-033239

Reference Standard

1,1′-[(4,6-Dimethyl-1,3-phenylene)bis(thio-2,1-phenylene)]bis[piperazine] chemical structure

1,1′-[(4,6-Dimethyl-1,3-phenylene)bis(thio-2,1-phenylene)]bis[piperazine]

CAS: 2099147-02-9
Formula: C₂₈H₃₄N₄S₂
MW: 490.7 g/mol

VQ-035330

Reference Standard

1,12-Dichlorododecane chemical structure

1,12-Dichlorododecane

CAS: 3922-28-9
Formula: C₁₂H₂₄Cl₂
MW: 239.22 g/mol

VQ-040324

Reference Standard

1,2 Dihydro Flumethasone acid

1,2 Dihydro Flumethasone acid

CAS: 28416-86-6
Formula: C₂₁H₂₈F₂O₅
MW: 398.44 g/mol

VQ-044720

Reference Standard

1,2 Dihydro Fluorometholone

1,2 Dihydro Fluorometholone

CAS: 378-36-9
Formula: C₂₂H₃₁FO₄
MW: 378.48 g/mol

VQ-025840

Reference Standard

1,2-alpha-Epoxy Exemestane chemical structure

1,2-alpha-Epoxy Exemestane

CAS: 159354-61-7
Formula: C₂₀H₂₄O₃
MW: 312.4 g/mol

VQ-022619

Reference Standard

1,2-Benzisoxazole-3-Acetic Acid chemical structure

1,2-Benzisoxazole-3-Acetic Acid

CAS: 4865-84-3
Formula: C₉H₇NO₃
MW: 177.16 g/mol

VQ-034766

Reference Standard

1,2-Benzisoxazole-3-carboxamide chemical structure

1,2-Benzisoxazole-3-carboxamide

CAS: 52046-80-7
Formula: C₈H₆N₂O₂
MW: 162.15 g/mol

VQ-032963

Reference Standard

1,2-Bis((2,4-dimethylphenyl)thio)benzene chemical structure

1,2-Bis((2,4-dimethylphenyl)thio)benzene

CAS: 2368241-98-7
Formula: C₂₂H₂₂S₂
MW: 350.5 g/mol

VQ-028762

Reference Standard

1,2-Bis(1-methyl-1H-imidazol-2-yl)disulfane chemical structure

1,2-Bis(1-methyl-1H-imidazol-2-yl)disulfane

CAS: 61747-29-3
Formula: C₈H₁₀N₄S₂
MW: 226.3 g/mol

VQ-042480

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