Orotic acid (zinc), a precursor for pyrimidine nucleotide and RNA biosynthesis, is released from mitochondrial dihydroorotate dehydrogenase (DHODH) and converted to UMP by cytoplasmic UMP synthase. Orotic acid (zinc) is measured in routine newborn screening for urea cycle abnormalities. Orotic acid (zinc) causes hepatic steatosis and hepatomegaly in rats.

Physicochemical Properties

Molecular Formula	C5H4N2O4ZN0.5
Molecular Weight	188.79
Exact Mass	373.948
CAS #	68399-76-8
Related CAS #	Orotic acid;65-86-1;Orotic acid potassium;24598-73-0
PubChem CID	108934
Appearance	White to off-white solid powder
Hydrogen Bond Donor Count	4
Hydrogen Bond Acceptor Count	8
Rotatable Bond Count	0
Heavy Atom Count	23
Complexity	262
Defined Atom Stereocenter Count	0
InChi Key	LUALAXHLCYKCNS-UHFFFAOYSA-N
InChi Code	InChI=1S/2C5H4N2O4.Zn/c2*8-3-1-2(4(9)10)6-5(11)7-3;/h2*1H,(H,9,10)(H2,6,7,8,11);
Chemical Name	2,4-dioxo-1H-pyrimidine-6-carboxylic acid;zinc
HS Tariff Code	2934.99.9001
Storage	Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.
Shipping Condition	Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Biological Activity

Targets	Human Endogenous Metabolite
ln Vitro	For utilization in the pyrimidine salvage pathway, orotic acid—found in milk and dairy products—is converted to uridine primarily in the liver, kidney, and erythrocytes[2].
ln Vivo	Ornithine transcarbamylase deficiency (OTCD) is one of the urea cycle diseases (UCDs) that can be measured with orotic acid[2]. Orotic acid (1.0% addition to the diet; po for 3–10 d) reduces the purine/pyrimidine ratio of hepatic acid-soluble nucleotides by day 3 and causes fatty liver growth by day 7[3].
References	[1]. Orotate (orotic acid): An essential and versatile molecule. Nucleosides Nucleotides Nucleic Acids. [2]. The role of orotic acid measurement in routine newborn screening for urea cycle disorders. J Inherit Metab Dis. 2020 Nov 15. [3]. Orotic acid-induced metabolic changes in the rat. J Nutr. 1980 Apr;110(4):816-21.
Additional Infomation	An intermediate product in PYRIMIDINE synthesis which plays a role in chemical conversions between DIHYDROFOLATE and TETRAHYDROFOLATE.

Solubility Data

Solubility (In Vitro)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Solubility (In Vivo)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples. Injection Formulations (e.g. IP/IV/IM/SC) Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline) *Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution. Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil) Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals). Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)] *Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution. Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline) Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline) Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline) Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil) Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Oral Formulations Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium) Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals). Oral Formulation 3: Dissolved in PEG400 Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose Oral Formulation 6: Mixing with food powders Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	5.2969 mL	26.4845 mL	52.9689 mL
	5 mM	1.0594 mL	5.2969 mL	10.5938 mL
	10 mM	0.5297 mL	2.6484 mL	5.2969 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.