Calcium L-threonate

• CAS: 70753-61-6
• Catalog Number: ACM70753616
• Category: Main Products
• Molecular Weight: 310.27
• Molecular Formula: C8H14CaO10
• Synonyms: L-Threonic acid calcium salt
• IUPAC Name: calcium;(2R,3S)-2,3,4-trihydroxybutanoate
• SMILES: C(C(C(C(=O)[O-])O)O)O.C(C(C(C(=O)[O-])O)O)O.[Ca+2]
• InChI: InChI=1S/2C4H8O5.Ca/c2*5-1-2(6)3(7)4(8)9;/h2*2-3,5-7H,1H2,(H,8,9);/q;+2/p-2/t2*2-,3+;/m00./s1
• InChI Key: ZJXGOFZGZFVRHK-BALCVSAKSA-L
• Boiling Point: 518.9ºC at 760 mmHg
• Melting Point: >300 °C
• Flash Point: 281.7ºC
• Appearance: Powder
• EC Number: 615-158-1
• Exact Mass: 310.0212875
• Hazard Statements: Xi
• Hydrogen Bond Acceptor Count: 10
• Hydrogen Bond Donor Count: 6
• Isomeric SMILES: C([C@@H]([C@H](C(=O)[O-])O)O)O.C([C@@H]([C@H](C(=O)[O-])O)O)O.[Ca+2]
• Monoisotopic Mass: 310.0212875
• Rotatable Bond Count: 4
• Safety Description: S22-S24/25
• Topological Polar Surface Area: 202 Ų
• WGK Germany: 3

Case Study

Pharmacokinetic, Absorption-Enhancing and Safety Properties of Calcium L-Threonate

Wang, H. Y., Hu, P., & Jiang, J. Acta Pharmacologica Sinica, 2011, 32, 1555-1560.

Calcium L-threonate exhibited significant rapid absorption activity: in 12 healthy subjects, oral administration of 675-4050 mg calcium L-threonate reached a median tmax of 2.0 h, with mean elimination half-life of approximately 2.5 h across all doses. It demonstrated potent absorption-enhancing effects: food intake significantly increased Cmax from 32.3 to 39.1 mg/L and AUC₀-∞ from 152.9 to 203.6 h·mg/L (P<0.05), improving systemic exposure. Additionally, calcium L-threonate exerted favorable safety and non-accumulation properties: repeated dosing of 2025 mg twice daily for 4 days showed no systemic accumulation (accumulation index = 1.086), with only mild, transient diarrhea (3.8%) as the sole adverse event and no abnormal laboratory or ECG findings. Pharmacokinetic analyses confirmed dose-increased but non-proportional exposure, low urinary excretion (5.9%), and rapid clearance. These studies demonstrate that calcium L-threonate possesses significant pharmacokinetic, absorption-enhancing and safety properties.
The in vivo pharmacokinetic and safety profile was investigated in 26 healthy Han Chinese volunteers in an open-label, single and multiple-dose study. In the single-dose phase, 12 subjects received 675, 2025, 4050 mg (fasted) or 2025 mg (fed) in a 4-way crossover design. In the multiple-dose phase, 14 subjects received 2025 mg twice daily for 4 days. Plasma and urine L-threonate concentrations were measured by HPLC-MS/MS; pharmacokinetic parameters were calculated by non-compartmental analysis. Safety was evaluated via adverse events, laboratory tests, ECG and vital signs. The results verified that calcium L-threonate is rapidly absorbed, food-enhanced, non-accumulating, and well-tolerated in humans.

Bioavailable, Safe and Bone-Supporting Properties of Calcium L-Threonate

The EFSA Journal, 2008, 866, 1-20.

The bioavailability, toxicological profile and nutritional efficacy of calcium L-threonate (a novel calcium source derived from vitamin C metabolism) were studied using animal models, human trials and genotoxicity assays. The main bioactive components are calcium ion and L-threonate, with the L-threonate ligand as the core functional moiety responsible for its high bioavailability, safety and bone-supporting effects.
Calcium L-threonate exhibited significant bioavailable calcium-delivery activity: in rats, passive calcium absorption reached 82%-93%, much higher than calcium acetate and calcium gluconate; in dogs, the AUC was 188.26 (μg/mL)·hours, exceeding other calcium salts. It demonstrated potent bone-supporting effects: it increased femur calcium deposition, bone density and mechanical strength, prevented rickets in vitamin D-deficient mice, and restored serum calcium and phosphorus to normal levels. Additionally, calcium L-threonate exerted excellent safety properties: acute toxicity was extremely low (NOAEL = 4 g/kg bw/day in rats); no genotoxicity or reproductive/developmental toxicity was observed; daily supplemental calcium (200-400 mg) remained below the 2500 mg/day upper limit. Toxicological and histological analyses confirmed reversible thyroid changes only at very high doses, with no organ damage or chronic adverse effects. These studies demonstrate that calcium L-threonate possesses significant bioavailable, safe and bone-supporting properties.
The in vivo bioavailability and safety were investigated in rats, dogs, mice and healthy humans. Animal studies compared calcium uptake, bone mineralization and toxicity; genotoxicity was tested via Ames, chromosome aberration and micronucleus assays; reproductive safety was evaluated in prenatal and perinatal models. Human trials measured urinary and serum calcium changes. The results verified that calcium L-threonate provides highly absorbable calcium, supports skeletal health, and is safe for use in food supplements.

Custom Q&A

What is the molecular formula of Calcium L-threonate?

The molecular formula of Calcium L-threonate is C8H14CaO10.

What are the synonyms of Calcium L-threonate?

The synonyms of Calcium L-threonate include Calcium L-Threonate, L-Threonic acid calcium salt, Calcium (2R,3S)-2,3,4-trihydroxybutanoate, Calcium threonate, Threonine, calcium salt, and more.

What is the role of Calcium L-threonate in the mineralization process?

Calcium L-threonate is hypothesized to play a role in the mineralization process through its positive action on vitamin C.

What is the IUPAC name of Calcium L-threonate?

The IUPAC name of Calcium L-threonate is calcium;(2R,3S)-2,3,4-trihydroxybutanoate.

What is the InChI of Calcium L-threonate?

The InChI of Calcium L-threonate is InChI=1S/2C4H8O5.Ca/c2*5-1-2(6)3(7)4(8)9;/h2*2-3,5-7H,1H2,(H,8,9);/q;;+2/p-2/t2*2-,3+;/m00./s1.

What is the InChIKey of Calcium L-threonate?

The InChIKey of Calcium L-threonate is ZJXGOFZGZFVRHK-BALCVSAKSA-L.

What is the Canonical SMILES of Calcium L-threonate?

The Canonical SMILES of Calcium L-threonate is C(C(C(C(=O)[O-])O)O)O.C(C(C(C(=O)[O-])O)O)O.[Ca+2].

What is the CAS number of Calcium L-threonate?

The CAS number of Calcium L-threonate is 70753-61-6.

What is the molecular weight of Calcium L-threonate?

The molecular weight of Calcium L-threonate is 310.27g/mol.

How many hydrogen bond acceptor counts does Calcium L-threonate have?

Calcium L-threonate has 10 hydrogen bond acceptor counts.