1. Product Overview
3,7-Dihydroxypteridine-2,4(1H,3H)-dione (CAS 2765672-52-2), commonly known as Xanthine, is a purine alkaloid and a key intermediate in purine metabolism. With the molecular formula C₅H₄N₄O₂ and a molecular weight of 152.11 g/mol, xanthine is the deaminated product of guanine (via guanase) and the methylated precursor to uric acid (via xanthine oxidase). It is a structural isomer of hypoxanthine and a core scaffold in the purine nucleoside/nucleotide family. Xanthine serves as a critical reference standard and substrate for studying purine catabolism, xanthine oxidase enzymology, and the pathophysiology of hyperuricemia and gout.
2. Key Features and Benefits
• Central Purine Catabolite: Occupies the pivotal position in the purine degradation cascade: Guanine → Xanthine → Uric Acid, making it indispensable for studying purine nucleotide turnover.
• Xanthine Oxidase (XO) Substrate: Directly acted upon by xanthine oxidase (Km ~10–20 μM) to produce uric acid; used extensively in XO activity assays, inhibitor screening (e.g., allopurinol, febuxostat), and enzyme kinetics studies.
• Adenosine Receptor Ligand: Functions as a low-affinity ligand for adenosine A1, A2A, and A3 receptors, serving as a reference in purinergic signaling research.
• Metabolically Stable Isostere: The 3,7-dihydroxy-2,4-dione core is a bioisostere of hypoxanthine (6-hydroxypurine), enabling structure-activity studies in nucleoside analog design.
• High Purity & Batch Consistency: Supplied at ≥95% or ≥98% (HPLC), with full CoA including ¹H NMR, UV-Vis, and LC-MS verification.
3. Major Applications
• Purine Metabolism & Gout Research: Used to investigate the biochemical basis of hyperuricemia, gout, and Lesch-Nyhan syndrome (HPRT deficiency), where xanthine and uric acid levels are dysregulated.
• Xanthine Oxidase (XO) Assays: Employed as the standard substrate for measuring XO activity in tissue extracts, cell lysates, and purified enzyme preparations; used in high-throughput screening (HTS) for novel XO inhibitors.
• Drug Discovery — XO Inhibitors: Serves as a competitive substrate in inhibitor validation assays for anti-gout drugs (allopurinol, oxypurinol, febuxostat, topiroxostat).
• Adenosine Receptor Pharmacology: Applied in binding and functional assays to characterize A1/A2A/A3 receptor ligands and study purinergic signaling in CNS, cardiovascular, and immune systems.
• Nucleoside Analog Development: Used as a scaffold for synthesizing xanthine-based nucleoside analogs with antiviral, anticancer, or immunomodulatory activity.
• Clinical & Forensic Toxicology: Employed as an analytical standard for quantifying xanthine and related purines in biological fluids (plasma, urine) via HPLC-UV, LC-MS/MS.
4. Technical Specifications
Item Description
Product Name 3,7-Dihydroxypteridine-2,4(1H,3H)-dione (Xanthine)
Synonyms Xanthine; 3,7-Dihydro-1H-purine-2,6-dione; Xanthic Oxide; Pseudoxanthine; Diurex; 2,6-Dioxopurine
CAS Number 2765672-52-2
Molecular Formula C₅H₄N₄O₂
Molecular Weight 152.11 g/mol
MDL Number —
PubChem CID 135403508
Assay (Purity) ≥95% / ≥98% (HPLC)
Appearance White crystalline powder
Melting Point >300 °C (sublimes, does not melt at atmospheric pressure)
Boiling Point Not applicable (sublimes)
Density ~1.85 g/cm³ (Predicted)
pKa (Literature) pKa₁ ≈ 7.7 (N-H); pKa₂ ≈ 11.1 (N-H deprotonation)
Calculated LogP -1.2 to -0.8 (highly polar/hydrophilic)
Polar Surface Area (PSA) 96.4 Ų
Hydrogen Bond Donors 2 (N-H ×2)
Hydrogen Bond Acceptors 4 (C=O ×2, N×2)
Rotatable Bonds 0 (rigid purine core)
Solubility Slightly Soluble: Water (~0.5–1 mg/mL at 25°C; more soluble at pH >8), Dilute NaOH/KOH (pH-dependent), Hot water (~5 mg/mL at 100°C).
Soluble:Dilute ammonia, DMF (slightly), DMSO (slightly).
Insoluble:Methanol, Ethanol, DCM, Chloroform, THF, Acetone, Hexane, Ether.
Spectral Data (Literature) ¹H NMR (DMSO‑d₆, 400 MHz): δ 10.85 (s, 1H, N1-H), 10.95 (s, 1H, N3-H), 11.50 (s, 1H, N7-H), 7.85 (s, 1H, C8-H).
¹³C NMR (DMSO‑d₆):δ 110.0 (C5), 140.0 (C8), 150.5 (C2), 155.0 (C4), 156.5 (C6).
UV-Vis (H₂O, pH 7):λmax ≈ 267 nm (ε ≈ 9,800 M⁻¹cm⁻¹).
SMILES Oc1nc2c(n1)nc[nH]c2=O
InChI Key IJDNQMDRTMLWQE-UHFFFAOYSA-N
Storage (Powder) Room Temperature or 2–8 °C, sealed, protected from light & moisture; stable ≥24+ months
HS Code 2933.59.90 / 3822.90.00 (Reference Standard)
5. Storage and Handling
• Storage: Store in a tightly sealed container at room temperature or 2–8 °C, protected from light and moisture. Xanthine is a stable, non-hygroscopic solid with excellent long-term stability—no special atmosphere required. Stable for ≥24 months from date of manufacture.
• Handling: No special precautions needed beyond standard laboratory PPE. Dissolve in dilute NaOH (0.1–1 M) for aqueous work, or in DMF/DMSO for organic-phase reactions. The compound is non-toxic at typical research concentrations.
• Solution Preparation: For XO assays, dissolve in 0.1 M NaOH to 10–50 mM stock, then dilute into assay buffer (pH 7.5–8.0, typically Tris or phosphate buffer) immediately before use. Final substrate concentration in assays: 50–200 μM.
• pH-Dependent Solubility: Xanthine is a weak diprotic acid; solubility increases dramatically above pH 8 (deprotonation of N-H groups). For neutral pH work, prepare stocks in DMSO and dilute into aqueous buffer (final DMSO ≤1%).
• Solution Stability: Aqueous solutions are stable for several days at 4°C; for long-term storage, aliquot and freeze at -20°C. Avoid repeated freeze-thaw cycles.
6. Safety Summary (Full SDS Highlights)
• GHS Classification: Not classified as hazardous (non-toxic, non-corrosive, non-flammable per typical purine alkaloids).
• Signal Word: No signal word (non-hazardous at research concentrations).
• Hazard Statements: None under normal handling conditions.
• Precautionary Statements: Standard laboratory hygiene practices.
• First Aid Measures:
• Inhalation: Remove to fresh air. Seek medical attention if symptoms persist.
• Skin Contact: Wash with soap and water. Seek medical advice if irritation develops.
• Eye Contact: Flush with water for 15 minutes. Seek medical attention if irritation persists.
• Ingestion: Rinse mouth. Drink water. Seek medical advice if large quantity ingested.
• Fire-Fighting Measures:
• Suitable Extinguishing Media: Water spray, alcohol-resistant foam, dry chemical, or CO₂.
• Special Hazards: Combustion may produce CO, NOₓ. No special hazards expected for this purine compound.
• Spill Response: Sweep up and place in suitable container. No special precautions needed.
• Handling & Storage: Standard laboratory conditions. Store at room temperature, protected from light.
• Intended Use: For laboratory research and development ONLY. Not for human or veterinary therapeutic, diagnostic, or food use.
