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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

2-Cyanoethyl (S)-4-(4-cyano-2-methoxyphenyl)-5-ethoxy-2,8-dimethyl-1,4-dihydro-1,6-naphthyridine-3-carboxylate chemical structure

2-Cyanoethyl (S)-4-(4-cyano-2-methoxyphenyl)-5-ethoxy-2,8-dimethyl-1,4-dihydro-1,6-naphthyridine-3-carboxylate

CAS: 2640574-73-6
Formula: C₂₄H₂₄N₄O₄
MW: 432.5 g/mol

VQ-025785

Reference Standard

2-Cyclopentylidene-2-phenylacetic Acid chemical structure

2-Cyclopentylidene-2-phenylacetic Acid

CAS: 126497-27-6
Formula: C₁₃H₁₄O₂
MW: 202.25 g/mol

VQ-031024

Reference Standard

2-Cyclopropyl-4-(4-fluorophenyl)-quinolyl-3-methylbromide chemical structure

2-Cyclopropyl-4-(4-fluorophenyl)-quinolyl-3-methylbromide

CAS: 154057-56-4
Formula: C₁₉H₁₅BrFN
MW: 356.2 g/mol

VQ-033227

Reference Standard

2-Deamino-(2,3-dihydro-2-oxo) Penciclovir chemical structure

2-Deamino-(2,3-dihydro-2-oxo) Penciclovir

CAS: 108970-74-7
Formula: C₂₁H₃₀Cl₃NO₁₀
MW: 562.8 g/mol

VQ-033090

Reference Standard

2-Debenzoyl Paclitaxel 2-Pentanoate chemical structure

2-Debenzoyl Paclitaxel 2-Pentanoate

CAS: 213767-22-7
Formula: C₄₅H₅₅NO₁₄
MW: 833.9 g/mol

VQ-027355

Reference Standard

2-Debenzoyl-2-pentenoyl Docetaxel chemical structure

2-Debenzoyl-2-pentenoyl Docetaxel

CAS: 1412898-66-8
Formula: C₄₁H₅₅NO₁₄
MW: 785.9 g/mol

VQ-022414

Reference Standard

2-Demethoxy-2-chloro Urapidil chemical structure

2-Demethoxy-2-chloro Urapidil

CAS: 34661-73-9
Formula: C₁₉H₂₆ClN₅O₂
MW: 391.9 g/mol

VQ-035059

Reference Standard

2-Demethoxy-4-methoxy Urapidil chemical structure

2-Demethoxy-4-methoxy Urapidil

CAS: 34661-79-5
Formula: C₂₀H₂₉N₅O₃
MW: 387.5 g/mol

VQ-028591

Reference Standard

2-Deoxy-2-chloro-D-glucose chemical structure

2-Deoxy-2-chloro-D-glucose

CAS: 14685-79-1
Formula: C₆H₁₁ClO₅
MW: 198.6 g/mol

VQ-030781

Reference Standard

2-Deoxy-2,2-difluoro-4,5-O-isopropylidene-D-erythro-pentonic Acid Ethyl Ester chemical structure

2-Deoxy-2,2-difluoro-4,5-O-isopropylidene-D-erythro-pentonic Acid Ethyl Ester

CAS: 95058-92-7
Formula: C₁₀H₁₆F₂O₅
MW: 254.23 g/mol

VQ-030963

Reference Standard

2-Deoxy-2,2-difluoro-D-erythro-ribofuranose-3,5-dibenzoate 1-Methanesulfonate chemical structure

2-Deoxy-2,2-difluoro-D-erythro-ribofuranose-3,5-dibenzoate 1-Methanesulfonate

CAS: 122111-11-9
Formula: C₂₀H₁₈F₂O₈S
MW: 456.4 g/mol

VQ-037497

Reference Standard

2-Deoxy-D-erythro-pentopyranosyl Chloride Bis(4-methylbenzoate) (Mixture of α/β isomers) chemical structure

2-Deoxy-D-erythro-pentopyranosyl Chloride Bis(4-methylbenzoate) (Mixture of α/β isomers)

CAS: 20535-28-8
Formula: C₂₁H₂₁ClO₅
MW: 388.8 g/mol

VQ-030096

Reference Standard

2-Deoxystreptamine, Dihydrobromide chemical structure

2-Deoxystreptamine, Dihydrobromide

CAS: 84107-26-6
Formula: C₆H₁₆Br₂N₂O₃
MW: 324.01 g/mol

VQ-025978

Reference Standard

2-Descyano-2-ethyl Formyl-tofacitinib chemical structure

2-Descyano-2-ethyl Formyl-tofacitinib

CAS: 1675248-18-6
Formula: C₁₈H₂₅N₅O₃
MW: 359.4 g/mol

VQ-034306

Reference Standard

2-Dimethylaminoethyl Benzilate chemical structure

2-Dimethylaminoethyl Benzilate

CAS: 968-46-7
Formula: C₁₈H₂₁NO₃
MW: 299.4 g/mol

VQ-027183

Reference Standard

2-Dimethylaminophenol chemical structure

2-Dimethylaminophenol

CAS: 3743-22-4
Formula: C₈H₁₁NO
MW: 137.18 g/mol

VQ-039302

Reference Standard

2-Epi Docetaxel Impurity chemical structure

2-Epi Docetaxel Impurity

CAS: 133577-33-0
Formula: C₄₃H₅₃NO₁₄
MW: 807.9 g/mol

VQ-036760

Reference Standard

2-epi-Emtricitabine chemical structure

2-epi-Emtricitabine

CAS: 145416-34-8
Formula: C₈H₁₀FN₃O₃S
MW: 247.25 g/mol

VQ-022514

Reference Standard

2-Ethoxy-1-methoxy-4-(2-methylsulfonylethenyl)benzene chemical structure

2-Ethoxy-1-methoxy-4-(2-methylsulfonylethenyl)benzene

CAS: 1831833-38-5
Formula: C₁₂H₁₆O₄S
MW: 256.32 g/mol

VQ-024333

Reference Standard

2-Ethoxy-3H-benzo-imidazole-4-carboxylic acid chemical structure

2-Ethoxy-3H-benzo-imidazole-4-carboxylic acid

CAS: 1234834-29-7
Formula: C₁₀H₁₀N₂O₃
MW: 206.2 g/mol

VQ-035357

Reference Standard

2-Ethoxy-4-(2-((4aR,6S)-6-isobutyl-2,3,4,4a-tetrahydro-1H-pyrido[1,2-a]quinazolin-5(6H)-yl)-2-oxoethyl)benzoic Acid chemical structure

2-Ethoxy-4-(2-((4aR,6S)-6-isobutyl-2,3,4,4a-tetrahydro-1H-pyrido[1,2-a]quinazolin-5(6H)-yl)-2-oxoethyl)benzoic Acid

CAS: 2519482-33-6
Formula: C₂₇H₃₄N₂O₄
MW: 450.6 g/mol

VQ-043733

Reference Standard

2-Ethoxy-4-(2-((4aS,6S)-6-isobutyl-2,3,4,4a-tetrahydro-1H-pyrido[1,2-a]quinazolin-5(6H)-yl)-2-oxoethyl)benzoic Acid chemical structure

2-Ethoxy-4-(2-((4aS,6S)-6-isobutyl-2,3,4,4a-tetrahydro-1H-pyrido[1,2-a]quinazolin-5(6H)-yl)-2-oxoethyl)benzoic Acid

CAS: 2519482-34-7
Formula: C₂₇H₃₄N₂O₄
MW: 450.6 g/mol

VQ-033503

Reference Standard

2-Ethoxy-5-[(4-methyl-1-piperazinyl)sulfonyl]- benzoic Acid chemical structure

2-Ethoxy-5-[(4-methyl-1-piperazinyl)sulfonyl]- benzoic Acid

CAS: 194602-23-8
Formula: C₁₄H₂₀N₂O₅S
MW: 328.39 g/mol

VQ-042161

Reference Standard

2-Ethoxybenzamidine Hydrochloride chemical structure

2-Ethoxybenzamidine Hydrochloride

CAS: 18637-00-8
Formula: C₉H₁₃ClN₂O
MW: 200.66 g/mol

VQ-032473

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