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Heterocyclic Building Blocks

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  • 4-Amino-6-hydroxy-2-mercaptopyrimidine hydrate

    Purity:
    ≥ 98% (Assay by titration)
    Synonym:
    6-Amino-2-thiouracil hydrate
    Catalog Number:
    43685
    CAS Number:
    65802-56-4
    Purity Limit:
    ≥ 98% (Assay by titration)
    MDL NO:
    MFCD00052384
    Molecular Formula:
    C4H5N3OS·xH2O
    Molecular Weight:
    143.16
    Specification Sheet SDS

  • Pyridazine

    Purity:
    ≥ 99% (GC)
    Catalog Number:
    43661
    CAS Number:
    289-80-5
    Purity Limit:
    ≥ 99% (GC)
    MDL NO:
    MFCD00006463
    Molecular Formula:
    C4H4N2
    Molecular Weight:
    80.09
    Specification Sheet SDS

  • 3-Methoxypyridazine

    Purity:
    ≥ 97% (GC)
    Catalog Number:
    43674
    CAS Number:
    19064-65-4
    Purity Limit:
    ≥ 97% (GC)
    MDL NO:
    MFCD00234098
    Molecular Formula:
    C5H6N2O
    Molecular Weight:
    110.12
    Specification Sheet SDS

  • 6-Chloro-3(2H)-pyridazinone

    Purity:
    ≥ 98% (GC)
    Synonym:
    3-Chloro-6-hydroxypyridazine
    Catalog Number:
    43660
    CAS Number:
    19064-67-6
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00233955
    Molecular Formula:
    C4H3ClN2O
    Molecular Weight:
    130.53
    Specification Sheet SDS

  • Ethyl 6-methyl-2-oxo-4-phenyl-1,2,3,4-tetrahydropyrimidine-5-carboxylate

    Purity:
    ≥ 98% (HPLC)
    Synonym:
    6-Methyl-2-oxo-4-phenyl-1,2,3,4-tetrahydropyrimidine-5-carboxylic acid ethyl ester
    Catalog Number:
    43681
    CAS Number:
    5395-36-8
    Purity Limit:
    ≥ 98% (HPLC)
    MDL NO:
    MFCD00124778
    Molecular Formula:
    C14H16N2O3
    Molecular Weight:
    260.29
    Specification Sheet SDS

  • Phthalazone

    Purity:
    ≥ 98% (GC)
    Synonym:
    Benzo[d]pyridazin-1(2Hone
    Catalog Number:
    43672
    CAS Number:
    119-39-1
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00006892
    Molecular Formula:
    C8H6N2O
    Molecular Weight:
    146.15
    Specification Sheet SDS

  • 2,4,6-Triamino-5-nitrosopyrimidine

    Purity:
    ≥ 98% (HPLC)
    Catalog Number:
    43677
    CAS Number:
    1006-23-1
    Purity Limit:
    ≥ 98% (HPLC)
    MDL NO:
    MFCD00006096
    Molecular Formula:
    C4H6N6O
    Molecular Weight:
    154.13
    Specification Sheet SDS

  • 4,5-Dihydro-6-methyl-3(2H)-pyridazinone

    Purity:
    ≥ 98% (GC)
    Catalog Number:
    43663
    CAS Number:
    5157-08-4
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00006455
    Molecular Formula:
    C5H8N2O
    Molecular Weight:
    112.13
    Specification Sheet SDS

  • 1,4,5,6-Tetrahydro-6-oxopyridazine-3-carboxylic acid

    Purity:
    ≥ 98% (HPLC)
    Catalog Number:
    43668
    CAS Number:
    27372-38-9
    Purity Limit:
    ≥ 98% (HPLC)
    MDL NO:
    MFCD00052030
    Molecular Formula:
    C5H6N2O3
    Molecular Weight:
    142.11
    Specification Sheet SDS

  • Ethyl 2-amino-4-hydroxypyrimidine-5-carboxylate

    Purity:
    ≥ 98% (GC)
    Synonym:
    2-Amino-4-hydroxypyrimidine-5-carboxylic acid ethyl ester
    Catalog Number:
    43676
    CAS Number:
    15400-53-0
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00039708
    Molecular Formula:
    C7H9N3O3
    Molecular Weight:
    183.17
    Specification Sheet SDS

  • 6-Phenylisocytosine

    Purity:
    ≥ 98% (HPLC)
    Synonym:
    2-Amino-6-phenyl-4(1H-pyrimidinone
    Catalog Number:
    43680
    CAS Number:
    56741-94-7
    Purity Limit:
    ≥ 98% (HPLC)
    MDL NO:
    MFCD00466412
    Molecular Formula:
    C10H9N3O
    Molecular Weight:
    187.2
    Specification Sheet SDS

  • 3-Methylpyridazine

    Purity:
    ≥ 97% (GC)
    Catalog Number:
    43671
    CAS Number:
    1632-76-4
    Purity Limit:
    ≥ 97% (GC)
    MDL NO:
    MFCD00006469
    Molecular Formula:
    C5H6N2
    Molecular Weight:
    94.12
    Specification Sheet SDS

  • 3,5-Diisopropylpyrazole

    Purity:
    ≥ 98% (GC)
    Catalog Number:
    43655
    CAS Number:
    17536-00-4
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00671516
    Molecular Formula:
    C9H16N2
    Molecular Weight:
    152.24
    Specification Sheet SDS

  • 6-Methylphthalazine

    Purity:
    ≥ 98% (GC)
    Catalog Number:
    43666
    CAS Number:
    78032-05-0
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD03844800
    Molecular Formula:
    C9H8N2
    Molecular Weight:
    144.18
    Specification Sheet SDS

  • Methylmaleic hydrazide

    Purity:
    ≥ 98% (GC)
    Synonym:
    1,2-Dihydro-4-methyl-3,6-pyridazinedione
    Catalog Number:
    43664
    CAS Number:
    5754-18-7
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00067746
    Molecular Formula:
    C5H6N2O2
    Molecular Weight:
    126.12
    Specification Sheet SDS

  • 3-Aminopyridazine

    Purity:
    ≥ 98% (GC)
    Catalog Number:
    43659
    CAS Number:
    5469-70-5
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD01529869
    Molecular Formula:
    C4H5N3
    Molecular Weight:
    95.11
    Specification Sheet SDS

  • Pyrimidine-5-carboxylic acid

    Purity:
    ≥ 97% (GC)
    Catalog Number:
    43675
    CAS Number:
    4595-61-3
    Purity Limit:
    ≥ 97% (GC)
    MDL NO:
    MFCD00856162
    Molecular Formula:
    C5H4N2O2
    Molecular Weight:
    124.1
    Specification Sheet SDS

  • 1-Methylpyrazole-4-carboxylic acid

    Purity:
    ≥ 98% (GC)
    Catalog Number:
    43649
    CAS Number:
    5952-92-1
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00159641
    Molecular Formula:
    C5H6N2O2
    Molecular Weight:
    126.12
    Specification Sheet SDS

  • 3-Methyl-1-p-tolyl-5-pyrazolone

    Purity:
    ≥ 99% (Assay)
    Catalog Number:
    43651
    CAS Number:
    86-92-0
    Purity Limit:
    ≥ 99% (Assay)
    MDL NO:
    MFCD00035708
    Molecular Formula:
    C11H12N2O
    Molecular Weight:
    188.23
    Specification Sheet SDS

  • 3,5-Dimethyl-1-phenylpyrazole

    Purity:
    ≥ 98% (GC)
    Catalog Number:
    43642
    CAS Number:
    1131-16-4
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00020728
    Molecular Formula:
    C11H12N2
    Molecular Weight:
    172.23
    Specification Sheet SDS

  • 4-Nitrophthalic hydrazide

    Purity:
    ≥ 98% (HPLC)
    Synonym:
    4-Nitrophthalhydrazide
    Catalog Number:
    43658
    CAS Number:
    3682-19-7
    Purity Limit:
    ≥ 98% (HPLC)
    MDL NO:
    MFCD00006891
    Molecular Formula:
    C8H5N3O4
    Molecular Weight:
    207.15
    Specification Sheet SDS

  • 3(2H)-Pyridazinone

    Purity:
    ≥ 96% (GC)
    Catalog Number:
    43665
    CAS Number:
    504-30-3
    Purity Limit:
    ≥ 96% (GC)
    MDL NO:
    MFCD00099605
    Molecular Formula:
    C4H4N2O
    Molecular Weight:
    96.09
    Specification Sheet SDS

  • 6-Hydroxypyridazine-3-carboxylic acid monohydrate

    Purity:
    ≥ 98% (HPLC)
    Catalog Number:
    43667
    CAS Number:
    306934-80-5
    Purity Limit:
    ≥ 98% (HPLC)
    MDL NO:
    MFCD09064936
    Molecular Formula:
    C5H4N2O3·H2O
    Molecular Weight:
    158.12
    Specification Sheet SDS

  • 6-Phenyl-3(2H)-pyridazinone

    Purity:
    ≥ 98% (GC)
    Synonym:
    3-Hydroxy-6-phenylpyridazine
    Catalog Number:
    43657
    CAS Number:
    2166-31-6
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00114953
    Molecular Formula:
    C10H8N2O
    Molecular Weight:
    172.19
    Specification Sheet SDS

  • 4-Methylpyridazine

    Purity:
    ≥ 98% (GC)
    Catalog Number:
    43662
    CAS Number:
    1120-88-3
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00011594
    Molecular Formula:
    C5H6N2
    Molecular Weight:
    94.12
    Specification Sheet SDS

  • 4-Benzoyl-3-methyl-1-phenyl-5-pyrazolone

    Purity:
    ≥ 98% (HPLC)
    Catalog Number:
    43641
    CAS Number:
    4551-69-3
    Purity Limit:
    ≥ 98% (HPLC)
    MDL NO:
    MFCD00003136
    Molecular Formula:
    C17H14N2O2
    Molecular Weight:
    278.31
    Specification Sheet SDS

  • Pyridazine-4-carboxylic acid

    Purity:
    ≥ 98% (GC)
    Catalog Number:
    43656
    CAS Number:
    50681-25-9
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00011576
    Molecular Formula:
    C5H4N2O2
    Molecular Weight:
    124.1
    Specification Sheet SDS

  • 4-Methyl-1-phenyl-3-pyrazolidone

    Purity:
    ≥ 98% (HPLC)
    Synonym:
    4-methyl-3-oxo-1-phenylpyrazolidine
    Catalog Number:
    43630
    CAS Number:
    2654-57-1
    Purity Limit:
    ≥ 98% (HPLC)
    MDL NO:
    MFCD00044800
    Molecular Formula:
    C10H12N2O
    Molecular Weight:
    176.22
    Specification Sheet SDS

  • 3-Methyl-5-pyrazolone

    Purity:
    ≥ 99% (HPLC)
    Catalog Number:
    43652
    CAS Number:
    108-26-9
    Purity Limit:
    ≥ 99% (HPLC)
    MDL NO:
    MFCD00020699
    Molecular Formula:
    C4H6N2O
    Molecular Weight:
    98.11
    Specification Sheet SDS

  • 2-(1-Pyrazolyl)pyridine

    Purity:
    ≥ 98% (GC)
    Catalog Number:
    43645
    CAS Number:
    25700-11-2
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD09033534
    Molecular Formula:
    C8H7N3
    Molecular Weight:
    145.17
    Specification Sheet SDS

  • 3-Amino-1-phenyl-2-pyrazolin-5-one

    Purity:
    ≥ 98% (HPLC)
    Catalog Number:
    43637
    CAS Number:
    4149-06-8
    Purity Limit:
    ≥ 98% (HPLC)
    MDL NO:
    MFCD00003137
    Molecular Formula:
    C9H9N3O
    Molecular Weight:
    175.19
    Specification Sheet SDS

  • Methyl pyrazole-3-carboxylate

    Purity:
    ≥ 98% (GC)
    Synonym:
    Pyrazole-3-carboxylic acid methyl ester
    Catalog Number:
    43646
    CAS Number:
    15366-34-4
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00649381
    Molecular Formula:
    C5H6N2O2
    Molecular Weight:
    126.12
    Specification Sheet SDS

  • 3-Methyl-1-(3'-sulfoamidophenyl)-5-pyrazolone

    Purity:
    ≥ 95% (Assay by titration)
    Catalog Number:
    43653
    CAS Number:
    89-29-2
    Purity Limit:
    ≥ 95% (Assay by titration)
    MDL NO:
    MFCD00035707
    Molecular Formula:
    C10H11N3O3S
    Molecular Weight:
    253.28
    Specification Sheet SDS

  • Methyl 5-methylpyrazole-3-carboxylate

    Purity:
    ≥ 98% (GC)
    Synonym:
    5-Methylpyrazole-3-carboxylic acid methyl ester
    Catalog Number:
    43647
    CAS Number:
    25016-17-5
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD03778987
    Molecular Formula:
    C6H8N2O2
    Molecular Weight:
    140.14
    Specification Sheet SDS

  • 3-Phenylpyrazole-5-carboxylic acid hydrate

    Purity:
    ≥ 97% (HPLC)
    Catalog Number:
    43638
    CAS Number:
    5071-61-4
    Purity Limit:
    ≥ 97% (HPLC)
    MDL NO:
    MFCD01248821
    Molecular Formula:
    C10H8N2O2·xH2O
    Molecular Weight:
    188.19
    Specification Sheet SDS

  • 3-Carboxy-1-(4-sulfophenyl)-5-pyrazolone sodium salt

    Purity:
    ≥ 98% (HPLC)
    Synonym:
    5-Oxo-1-(4-sulfophenyl)-2-pyrazoline-3-carboxylic acid sodium salt
    Catalog Number:
    43640
    CAS Number:
    52126-51-9
    Purity Limit:
    ≥ 98% (HPLC)
    MDL NO:
    MFCD00059720
    Molecular Formula:
    C10H7N2NaO6S
    Molecular Weight:
    306.22
    Specification Sheet SDS

  • 1-Benzyl-1H-pyrazole-4-carboxaldehyde

    Purity:
    ≥ 98% (GC)
    Catalog Number:
    43632
    CAS Number:
    63874-95-3
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD02179567
    Molecular Formula:
    C11H10N2O
    Molecular Weight:
    186.21
    Specification Sheet SDS

  • 3,5-Dimethylpyrazole-1-carboxamide

    Purity:
    ≥ 98% (GC)
    Synonym:
    1-Carbamoyl-3,5-dimethylpyrazole
    Catalog Number:
    43648
    CAS Number:
    934-48-5
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00003126
    Molecular Formula:
    C6H9N3O
    Molecular Weight:
    139.16
    Specification Sheet SDS

  • 1-(4-Nitrophenyl)-3-methyl-5-pyrazolone

    Purity:
    ≥ 98% (GC)
    Synonym:
    3-Methyl-1-(4-nitrophenyl)-5-pyrazolone
    Catalog Number:
    43644
    CAS Number:
    6402-09-1
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00020751
    Molecular Formula:
    C10H9N3O3
    Molecular Weight:
    219.2
    Specification Sheet SDS

  • 1-Ethylpyrazole

    Hazmat
    Purity:
    ≥ 98% (GC)
    Hazmat
    Catalog Number:
    43610
    CAS Number:
    2817-71-2
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD03444367
    Molecular Formula:
    C5H8N2
    Molecular Weight:
    96.13
    Specification Sheet SDS

  • 3-Amino-5-tert-butylpyrazole

    Purity:
    ≥ 98% (GC)
    Catalog Number:
    43643
    CAS Number:
    82560-12-1
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00067987
    Molecular Formula:
    C7H13N3
    Molecular Weight:
    139.2
    Specification Sheet SDS

  • 4-Methylpyrazole

    Purity:
    ≥ 98% (GC)
    Catalog Number:
    43636
    CAS Number:
    7554-65-6
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00005245
    Molecular Formula:
    C4H6N2
    Molecular Weight:
    82.11
    Specification Sheet SDS

  • 1-Phenyl-5-pyrazolone-3-carboxylic acid

    Purity:
    ≥ 98% (HPLC)
    Synonym:
    5-Oxo-1-phenyl-2-pyrazolin-3-carboxylic acid
    Catalog Number:
    43634
    CAS Number:
    119-18-6
    Purity Limit:
    ≥ 98% (HPLC)
    MDL NO:
    MFCD00037318
    Molecular Formula:
    C10H8N2O3
    Molecular Weight:
    204.19
    Specification Sheet SDS

  • 5-Amino-1-(p-tolyl)pyrazole-4-carbonitrile

    Purity:
    ≥ 93% (GC)
    Synonym:
    5-Amino-1-(4-methylphenyl)pyrazole-4-carbonitrile
    Catalog Number:
    43608
    CAS Number:
    103646-82-8
    Purity Limit:
    ≥ 93% (GC)
    MDL NO:
    MFCD00052944
    Molecular Formula:
    C11H10N4
    Molecular Weight:
    198.23
    Specification Sheet SDS

  • 4-Bromo-1-isopropylpyrazole

    Purity:
    ≥ 98% (GC)
    Catalog Number:
    43639
    CAS Number:
    313735-62-5
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD09801021
    Molecular Formula:
    C6H9BrN2
    Molecular Weight:
    189.06
    Specification Sheet SDS

  • Potassium tris(3,5-dimethylpyrazol-1-yl)borohydride

    Hazmat
    Purity:
    ≥ 98% (Assay by titration)
    Synonym:
    Potassium hydrotris(3,5-dimethylpyrazol-1-yl)borate
    Hazmat
    Catalog Number:
    43623
    CAS Number:
    17567-17-8
    Purity Limit:
    ≥ 98% (Assay by titration)
    MDL NO:
    MFCD00040342
    Molecular Formula:
    C15H22BKN6
    Molecular Weight:
    336.29
    Specification Sheet SDS

  • 4-Formylaminoantipyrine

    Purity:
    ≥ 98% (GC)
    Synonym:
    N-(1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)formamide
    Catalog Number:
    43614
    CAS Number:
    1672-58-8
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00085457
    Molecular Formula:
    C12H13N3O2
    Molecular Weight:
    231.26
    Specification Sheet SDS

  • 1-Phenylpyrazole

    Purity:
    ≥ 98% (GC)
    Catalog Number:
    43609
    CAS Number:
    1126-00-7
    Purity Limit:
    ≥ 98% (GC)
    MDL NO:
    MFCD00003112
    Molecular Formula:
    C9H8N2
    Molecular Weight:
    144.18
    Specification Sheet SDS

  • 3-Methyl-1-(4-sulfophenyl)-2-pyrazolin-5-one

    Purity:
    ≥ 97% (Assay by titration)
    Synonym:
    1-(4'-Sulfophenyl)-3-methyl-5-pyrazolone
    Catalog Number:
    43631
    CAS Number:
    89-36-1
    Purity Limit:
    ≥ 97% (Assay by titration)
    MDL NO:
    MFCD00020756
    Molecular Formula:
    C10H10N2O4S
    Molecular Weight:
    254.26
    Specification Sheet SDS

  • Pyrazole-3-carboxylic acid

    Purity:
    ≥ 98% (HPLC)
    Catalog Number:
    43616
    CAS Number:
    1621-91-6
    Purity Limit:
    ≥ 98% (HPLC)
    MDL NO:
    MFCD00077436
    Molecular Formula:
    C4H4N2O2
    Molecular Weight:
    112.09
    Specification Sheet SDS
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