A1784 Sigma



Synonym: (S)-2-{4-[(2,4-Diaminopteridin-6-yl)methylamino]benzamido}pentanedioic acid, 4-Amino-PGA, 4-Aminofolic acid, 4-Aminopteroyl-L-glutamic acid



Related Categories A-AM, Antitumor Agents, Apoptosis and Cell Cycle, Application Index, Bioactive Small Molecule Alphabetical Index,
assay   ≥85% (TLC)
form   powder
color   yellow
solubility   2 M NaOH: soluble50 mg/mL (Solutions may be stored for 1-2 days at 4°C.)
  DMSO: soluble (Solutions may be stored for 1-2 days at 4°C.)
absorption   ε1M/261 nm, 0.1 M NaOH 25,700
  ε1M/282 nm, 0.1 M NaOH 24,500
  ε1M/373 nm, 0.1 M NaOH 8,100
storage temp.   −20°C
Gene Information   human ... FPGS(2356)
mouse ... Fpgs(14287)



More potent, but more toxic, than methotrexate.


1 g in glass bottle

50 mg in glass bottle

Biochem/physiol Actions

Folic acid antagonist. Aminopterin is actively transported into cells by the folate transporter. In the cell, it is converted to a high molecular weight polyglutamate metabolite by folylpolyglutamate synthase that, in turn, binds to dihydrofolate reductase and inhibits its activity. Aminopterin-polyglutamate is degraded intracellularly by γ-glutamyl hydrolase.

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Safety Information

Signal word 
Hazard statements 
Precautionary statements 
UN 2811 6.1 / PGI
WGK Germany 


Certificate of Analysis

Certificate of Origin

Protocols & Articles


DNA Damage and Repair

Damage to cellular DNA is involved in mutagenesis and the development of cancer. The DNA in a human cell undergoes several thousand to a million damaging events per day, generated by both external (e...
Keywords: AGE, Alkylations, Apoptosis, Biochemistry, Cancer, Carcinogens, Catalysis, Clinical, DNA replication, Deaminations, Degradations, Eliminations, Environmental, Enzymology, Gene expression, Genetic, Infrared spectroscopy, Metabolites, Methylations, Mutagens, Oncology, Oxidations, Polymorphisms, Rearrangements, Recombination, Substitutions, Transcription, transformation

Discover Bioactive Small Molecules for Apoptosis

Apoptosis, or programmed cell death (PCD), is a selective process for the removal of unnecessary, infected or transformed cells in various biological systems. As it plays a role in the homeostasis of...
Keywords: Apoptosis, Bioactive small molecules, Cancer, Clinical, Diseases, Ligands, Neurodegenerative Diseases

Discover Bioactive Small Molecules for Cell Cycle Research

In proliferating cells, the cell cycle consists of four phases. Gap 1 (G1) is the interval between mitosis and DNA replication that is characterized by cell growth. Replication of DNA occurs during t...
Keywords: Apoptosis, Bioactive small molecules, Cancer, Cell division, Cell proliferation, DNA replication, Diseases, Genetic

Nucleotide Synthesis in Cancer Cells

Neoplastic cells are highly dependent on the de novo synthesis of nucleotides to maintain sufficient pools to support DNA replication and the production of RNA. The metabolic pathways supporting nucl...
Keywords: Biofiles, Cancer, Catalysis, Citric Acid Cycle, DNA replication, Gene expression, Glycolysis, Metabolic Pathways, Metabolism, Metabolites, Nucleotide Synthesis, PAGE, Pentose phosphate pathway, Pyrimidine synthesis, Support

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D6566 Dihydrofolate Reductase human, ≥80% (SDS-PAGE), recombinant, expressed in E. coli, ≥1 units/mg protein

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