65-86-1

Basic information

• Product Name: Orotic acid
• Synonyms: 1,2,3,6-tetrahydro-2,6-dioxo-4-pyrimidecarboxylicacid[qr];1,2,3,6-tetrahydro-2,6-dioxo-4-pyrimidinecarboxylicaci;2,6-Dihydroxy-4-pyrimidinecarboxylic acid;4-Pyrimidinecarboxylic acid, 1,2,3,6-tetrahydro-2,6-dioxo-;4-pyrimidinecarboxylicacid,1,2,3,6-tetrahydro-2,6-dioxo-[qr];6-carboxyuracil[qr];acideorotique(french)[qr];acidoorotico[qr]
• CAS NO: 65-86-1
• Molecular Formula: C₅H₄N₂O₄
• Molecular Weight: 156.1
• EINECS: 200-619-8
• Product Categories: Vitamin Ingredients;Daily-use cosmetics and medicine nucleic acid biological research;Inhibitors;pharmaceutical
• Mol File: 65-86-1.mol
• Article Data: 25

Chemical Properties

• Melting Point: >300°C
• Boiling Point: 280.29°C (rough estimate)
• Flash Point: 351.1 °C
• Appearance: White/Crystalline Powder
• Density: 1.6814 (rough estimate)
• Refractive Index: 1.4800 (estimate)
• Storage Temp.: Sealed in dry,Room Temperature
• PKA: pK1:1.8(+1);pK2:9.55(0) (25°C)
• Water Solubility: Slightly soluble
• Stability: Stable. Incompatible with strong oxidizing agents.
• Merck: 13,6942
• BRN: 383901
• CAS DataBase Reference: Orotic acid(CAS DataBase Reference)
• NIST Chemistry Reference: Orotic acid(65-86-1)
• EPA Substance Registry System: Orotic acid(65-86-1)

Safety Data

• Hazard Codes: Xn,Xi
• Statements: 22-36/37/38
• Safety Statements: 26-36/37/39-22-37/39
• WGK Germany: 3
• RTECS: RM3180000
• F: 10-21
• TSCA: Yes
• Hazardous Substances Data: 65-86-1(Hazardous Substances Data)

Usage

General Description

Different sources of media describe the General Description of 65-86-1 differently. You can refer to the following data:
1. Orotic acid (also known as pyrimidinecarboxylic acid) is a heterocyclic acid; it is also known as. Historically it was believed to be part of the vitamin B complex and was called vitamin B13, but it is now known that it is not a vitamin. It is well known as a precursor in biosynthesis of pyrimidines; in mammals it is released from the mitochondrial dihydroorotate dehydrogenase (DHODH) for conversion to UMP by the cytoplasmic UMP synthase enzyme[1]. OA is also a normal part of the diet, being found in milk and dairy products[5], and it is converted to uridine for use in the pyrimidine salvage pathway predominantly in liver, kidney and erythrocytes. Before its essential role as an intermediate of pyrimidine biosynthesis was established in the 1950s[3], the compound OA was discovered in whey (Greek oros) by Biscaro and Belloni (1905)[4]. Since then it has received attention from several different aspects. For example, it is proposed that the dietary orotate is beneficial for animals and humans obviously arose from its considerable natural amounts in milk and dairy products[5]. In addition, it also draw great attention from its medical potentials such as improvement of learning behavior of adult rats, neuro-protective effect for gerbils and cats under transient cerebral ischemia, and optimization of functions in normal and ischemic rat hearts[6-9].
2. White crystals or crystalline powder.

Metabolism

Orotate [orotic acid, OA] is the product of dihydroorotate dehydrogenase [DHODH], the fourth enzyme of pyrimidine [UMP] de novo synthesis [Fig. 1]. It is abundant in the serum and particularly urine of patients suffering from hereditary orotic academia or from enzyme defects in the urea cycle[10]. The sequence of six chemical reactions of UMP de novo synthesis is conserved from microorganisms to humans [Figure 1], although the organization of enzymes involved is different in eukaryotes[11-13]. In mammals, the six enzymes are coded by only three genes. The tri-functional CAD enzyme and the bifunctional UMP synthase each contain their appropriate catalytic activities on one polypeptide chain. The product of the third gene, dihydroorotate dehydrogenase [DHODH] holds a mitochondrial targeting sequence and a transmembrane domain at the N-terminus, which enable the enzyme to find its place in the inner mitochondrial membrane[14]. Through its electron acceptor, ubiquinone, DHODH is functionally united with the respiratory chain and can contribute to energy conservation in mitochondria. In turn, the formation of orotic acid [OA] by mitochondria, and hence the de novo synthesis of UMP, is strictly aerobic. In growth processes OA can be considered as a metabolic link between environmental oxygen tension and the proliferative capacity of cells[15].

Applications

Overview Orotic Acid is used in the preparation of therapeutic agents for chronic obstructive pulmonary disease [COPD] treatment[16]. As it is an intermediate in de novo pyrimidine biosynthesis, it may be used to study the specificity and kinetics of orotate phosphoribosyltransferase [OPRT] which catalyzes the reversible phosphoribosyl transfer from 5′-phospho-α-d-ribose 1′-diphosphate [PRPP] to orotic acid [OA], forming pyrophosphate and orotidine 5′-monophosphate [OMP][17]. Orotic acid can also be used as a starting material for the potential commercial bio-production of uridine 5′-monophosphate [UMP] by microbes such as Corynebacterium ammoniagenes [ATCC 6872] or Saccharomyces cerevisiae. Moreover, it may be used to study the AMPK/SREBP-1 dependent cell-signaling pathway and transcription regulation mechanisms associated with the induction hepatic lipogenesis[17]. Medical aspects OA has strong pharmacological potentials. The improvement of learning behavior of adult rats, neuro-protective effect for gerbils and cats under transient cerebral ischemia, and optimization of functions in normal and ischemic rat hearts were generally assigned to the precursor role of OA in cells for pyrimidine nucleotides and RNA[6-9]. The development of complexes and salts with metal ions [Mg2+, Zn2+, Ca2+, K+] and organic cations [e.g. choline, carnitine] exploited the favorable carrier function of OA for transportation and delivery of these ligands in living organisms to compensate deficiency syndromes[5]. Likewise, the construction of platinum, palladium and tin coordination compounds with OA for administration in cancer chemotherapy followed this principle[18]. The positive impact of OA preparations claimed for humans are highlighted by promises given in the public domain, such as beneficial cardiovascular effects, energy provision, improvement of body composition, and enhanced athletic performance. Study has also shown that OA may lower the serum cholesterol and lipid[19-21]. Orotic acid also has strong uricosuric effect, originating from its role as a true transport substrate for the anion exchangerURAT1 [encoded by human SLC22A12 gene] located at the luminal site of the tubule cells[22]. Dietary aspects The assumption that dietary orotate is beneficial for animals and humans obviously arose from its considerable natural amounts in milk and dairy products[5]. In the 1970s OA was proposed to increase the UDP-glucuronate pool for hepatic detoxification of bilirubin in the treatment of neonatal jaundice[5]. Another, underestimated, benefit of OA in the diet of newborns may be the establishment of the anaerobic OA-degrading intestinal microflora. Overall, it has strong potential to become a growth-enhancer for livestock. Central Nervous systems OA’s benefit for the brain, mentioned earlier, deserves closer attention. It can be assumed that a continuous supply of pyrimidine nucleotides is essential not only for the developing central nervous system[23], but equally for its plasticity, regeneration and neurotransmission: for example, some metabotropic P2Y receptor subtypes are sensitive to uridine nucleotides[24]. OA has putative protective and improvement effects of pyrimidine nucleotide pools, RNA synthesis, receptor saturation, repairing of ischeamia-induced membrane damage, which is explained by the function of OA as an intermediate in de novo UMP synthesis[25, 26]. Research field OA had became a compound of considerable interest as a tool for studying pyrimidine metabolism in cells, tissues and animals: monitoring precursors, nucleotide pools and the rate of RNA synthesis, differentiating between de novo and salvage/recycling pathways, searching for antimetabolites and anticancer drugs[27, 29]. Concurrently, the growth-promoting features of OA were still of interest, and OA was used on animals and humans, with various biochemical rationales, assumptions and expectations[28, 30]. When OA was an additive to pharmaceutical preparations, its benefits were attributed to its being an intermediate of pyrimidine biosynthesis and therefore augmenting uridine nucleotide pools which are required for nucleic acid synthesis and for all pyrimidine nucleotide dependent biosynthetic processes[31, 32].

References

https://www.springer.com/us/book/9780852002940 L?ffler, M.; Carrey E.; Zameitat, E. Orotic acid, more than just an intermediate of pyrimidine de novo synthesis, J. Genet. Genomics 2015, 42, 207–219. Reichard P.; Lagerkvist, U. The biogenesis of orotic acid in liver slices, Acta Chem. Scand. 1953, 7, 1207–1217. Biscaro, G.; Belloni E. About a new compound of the milk, Annuario della Soc. Chimica di Milano 1905, 11, 15. L?ffler, M.; Carrey E.; Zameitat, E. Orotic acid,more than just an intermediate of pyrimidine de novo synthesis, J. Genet. Genomics 2015, 42, 207–219. Ru?thrich, H.; Wetzel, W.; Matthies, H. Postnatal orotate treatment: effects on learning and memory in adult rats, Psychopharmacology 1979, 63, 25–28. Krug, M.; Koch, M.; Schoof, E.; Wagner, M.; Matthies, H. Methylglucamine orotate, a memory-improving drug, prolongs hippocampal long-term potentiation, Eur. J. Pharmacol. 1989, 173, 223–226. Akiho, H.; Iwai, A.; Katoh-Sudoh,M.; Tsukamoto, S.; Koshiya, K.; Yamaguchi, T. Neuroprotective effect of Y-39558, orotic acid ethylester, in gerbil forebrain ischemia, Jpn. J. Pharmacol. 1998, 76, 441–444. Vilskersts, R.; Liepinsh, E.; Kuka, J.; Cirule, H.; Veveris, M.; Kalvinsh, I.; Dambrova, M. Myocardial infarct size-limiting and anti-arrhythmic effects of mildronate orotate in the rat heart, Cardiovasc. Drug Ther. 2009, 21, 281–288. Webster, D.R., Becroft, D.M., van Gennip, A.H., van Kuilenburg, A.B.P., 2001. Hereditary orotic aciduria and other disorders of pyrimidine metabolism. In: Scriver, C.R., Beaudet, A.L., Sly,W.S., Valle, D. [Eds.], The Metabolic and Molecular Bases of Inherited Disease, Vol. II. Medical Publishing Division, McGraw-Hill, New York, USA, pp. 2663e2702. Jones, M.E. Pyrimidine nucleotide biosynthesis in animals: genes, enzymes, and regulation of UMP biosynthesis, Ann. Rev. Biochem. 1980, 49, 253–279. Evans, D.R.; Guy, H.I. Mammalian pyrimidine biosynthesis: fresh insights into an ancient pathway, J. Biol. Chem. 2004, 279, 33035–33038. L?fflerM.; Zameitat, E.. Pyrimidine biosynthesis and degradation [catabolism] in The Encyclopedia of Biological Chemistry, eds. W.J. Lennarz; M.D. Lane, Academic Press, Waltham, 2013, Vol III, pp. 712–718. Rawls, J.; Knecht, W.; Diekert, K.; Lill, R.; L?ffler, M. Requirements for the mitochondrial import and localization of dihydroorotate dehydrogenase, Eur. J. Biochem. 2000, 267, 2079– 2087. L?ffler, M.; Carrey, E.A.; Zameitat, E. Essential role of mitochondria in pyrimidine metabolism, in Tumor Cell Metabolism: Pathways, Regulation and Biology, eds. S. Mazurek; S. Shoshan, Springer,Wien, Austria, 2015, pp. 287–312 https://www.trc-canada.com/product-detail/?CatNum=O691500&CAS=50887-69-9%20&Chemical_Name=Orotic%20Acid%20Monohydrate&Mol_Formula=C?H?N?O??H?O https://www.sigmaaldrich.com/catalog/product/sigma/o2750?lang=en®ion=US Nath, M.; Vats, M.; Roy, P. Tri- and diorganotin[IV] complexes of biologically important orotic acid: synthesis, spectroscopic studies, in vitro anti-cancer, DNA fragmentation, enzyme assays and in vivo anti-inflammatory activities, Eur. J. Med. Chem. 2013, 9, 310–321. Kelley,W.N.; Greene,M.L.; Fox, I.H.; Rosenbloom, F.M.; Levy R.I.; Seegmiller, J.E. Effects of orotic acid on purine and lipoprotein metabolism in man, Metabolism 1979, 19, 1025–1035. Robinson, J.L.; Dombrowski, D.B. Effects of orotic acid ingestion on urinary and blood parameters in humans, Nutr. Res. 1983, 3, 407–415. Robinson, J.K.;Dombrowski,D.B.; Tauss, L.R.; Jones, L.R.Assessment in humans of hypolipidemia induced by orotic acid, Am. J. Clin.Nutr. 1985, 41, 605–608. Miura,D.;Anzai,N.; Jutabha, P.; Chanluang, S.;He, X.; Toshiyuki, F.; Endou,H.Human urate transporter 1 [hURAT1] mediates the transport of orotate, J. Physiol. Sci. 2011, 61, 253–257. Connolly, G.P., Duley, J.A., 1999. Uridine and its nucleotides: biological actions, therapeutic potentials. Trends Pharmacol. Sci. 20, 218e225. Von Ku¨gelen, I., 2006. Pharmacological profiles of cloned mammalian P2Yreceptor subtypes. Pharmacol. Therapeut. 110, 414e432. Akiho, H., Iwai, A., Katoh-Sudoh, M., Tsukamoto, S., Koshiya, K., Yamaguchi, T., 1997. Post-ischaemic treatment with orotic acid prevented neuronal injury in gerbil brain ischaemia. Neuroreport 8, 607e610. Akiho, H., Iwai, A., Katoh-Sudoh, M., Tsukamoto, S., Koshiya, K., Yamaguchi, T., 1998a. Neuroprotective effect of Y-39558, orotic acid ethylester, in gerbil forebrain ischemia. Jpn. J. Pharmacol. 76, 441e444. Heidelberger, C., 1965. Fluorinated pyrimidines. Prog. Nucleic Acid Res. Mol. Biol. 4, 1e50. O’Sullivan, W.J., 1973. Orotic acid. Aust. N. Z. J. Med. 3, 417e423. Kaneti, J.J., Golovinsky, E.V., 1971. Quantitative relationships between the electronic structure and biological activity of some analogues of orotic acid. Chem. Biol. Interact. 3, 421e428. Falk, M., 1985. Orotsa¨ure. Die Pharmazie 40, 377e383 Grisham, C.M., Garrett, R.H., Garrett, R., 2008. Biochemistry. Brooks Cole Publishing, Pacific Grove, USA. Voet, D., Voet, J.G., 2011. Biochemistry. John Wiley and Sons, New York, USA.

Chemical Properties

white crystalline powder

Originator

Lactinium, Roland

Uses

Different sources of media describe the Uses of 65-86-1 differently. You can refer to the following data:
1. Orotic acid is an intermediate in de novo pyrimidine biosynthesis that may be used to study the specificity and kinetics of orotate phosphoribosyltransferase (OPRT) which catalyzes the reversible phosphoribosyl transfer from 5?-phospho-α-d-ribose 1?-diphosphate (PRPP) to orotic acid (OA), forming pyrophosphate and orotidine 5?-monophosphate (OMP). It is used as a starting material for the potential commercial bioproduction of uridine 5?-monophosphate (UMP) by microbes such as Corynebacterium ammoniagenes (ATCC 6872) or Saccharomyces cerevisiae. It may be used to study the AMPK/SREBP-1 dependent cell signaling pathway and transcription regulation mechanisms that induce hepatic lipogenesis.
2. hepatoprotectant, uricosuric agent
3. An intermediate in de novo pyrimidine biosynthesis.

Definition

ChEBI: A pyrimidinemonocarboxylic acid that is uracil bearing a carboxy substituent at position C-6.

Manufacturing Process

91.7 g (0.5 mol) of trichloroacetyl chloride was cooled to -35°C in a glass vessel by means of a cooling brine. In the course of 3 h, 27.0 g (0.06 mol) of pure ketene was introduced through a tube. After completion of the reaction, the vessel was immediately put under dry nitrogen to prevent penetration of moisture. So γ,γ,γ-trichloroacetoacetylchloride was produced. The reaction mixture containing the γ,γ,γ-trichloroacetoacetyl chloride was transfered under nitrogen to a dropping funnel and in the course of 15 min was added with vigorous agitation to a suspension of 69.0 g (1.15 mole) of urea in 90.0 g of anhydrous acetic acid. Water cooling was used so that the reaction temperature would not exceed 40°C. After completion of the addition, the reaction mixture was heated as rapidly as possible to 115°C, and held at this temperature for 30 min. Subsequently there was cooling and one more 99.0 g of glacial acetic acid and 180.0 g of water were added. The precipitated 6-trichloromethyluracil was filtered off and dried at 60°C in a vacuum drying cabinet. The yield was 91.0 g or 80%. In a glass vessel equipped with an agitator, thermometer and pH electrode, 500 ml of water was placed and heated to 80°C. 50 g of 6trichloromethyluracil was then added. By means of the pH electrode, the addition of sodium hydroxide was automatically controlled so that the pH value throughout the whole hydrolysis was 6.5. Into, 165 ml of 5 N NaOH was consumed. Finally, the hydrolysis solution was cooled and the precipitated sodium orotate filtered off. The crude sodium orotate was again suspended at 80°C in water and brought into solution (pH 10.5) by addition of 30 ml of 5 N NaOH. After treatment with active charcoal, the solution was acidified with 30.0 g of 50% sulfuric acid. The solution was then cooled. The orotic acid was filtered off and carefully washed with water. After drying, 20.5 g of orotic acid, having a purity of 99.3% (titration) was obtained. This corresponds to a 60% yield.

Synthesis Reference(s)

Journal of the American Chemical Society, 69, p. 1382, 1947 DOI: 10.1021/ja01198a042

Air & Water Reactions

Slightly soluble in water.

Reactivity Profile

Carboxylic acids, such as Orotic acid, donate hydrogen ions if a base is present to accept them. They react in this way with all bases, both organic (for example, the amines) and inorganic. Their reactions with bases, called "neutralizations", are accompanied by the evolution of substantial amounts of heat. Neutralization between an acid and a base produces water plus a salt. Carboxylic acids with six or fewer carbon atoms are freely or moderately soluble in water; those with more than six carbons are slightly soluble in water. Soluble carboxylic acid dissociate to an extent in water to yield hydrogen ions. The pH of solutions of carboxylic acids is therefore less than 7.0. Many insoluble carboxylic acids react rapidly with aqueous solutions containing a chemical base and dissolve as the neutralization generates a soluble salt. Carboxylic acids in aqueous solution and liquid or molten carboxylic acids can react with active metals to form gaseous hydrogen and a metal salt. Such reactions occur in principle for solid carboxylic acids as well, but are slow if the solid acid remains dry. Even "insoluble" carboxylic acids may absorb enough water from the air and dissolve sufficiently in Orotic acid to corrode or dissolve iron, steel, and aluminum parts and containers. Carboxylic acids, like other acids, react with cyanide salts to generate gaseous hydrogen cyanide. The reaction is slower for dry, solid carboxylic acids. Insoluble carboxylic acids react with solutions of cyanides to cause the release of gaseous hydrogen cyanide. Flammable and/or toxic gases and heat are generated by the reaction of carboxylic acids with diazo compounds, dithiocarbamates, isocyanates, mercaptans, nitrides, and sulfides. Carboxylic acids, especially in aqueous solution, also react with sulfites, nitrites, thiosulfates (to give H2S and SO3), dithionites (SO2), to generate flammable and/or toxic gases and heat. Their reaction with carbonates and bicarbonates generates a harmless gas (carbon dioxide) but still heat. Like other organic compounds, carboxylic acids can be oxidized by strong oxidizing agents and reduced by strong reducing agents. These reactions generate heat. A wide variety of products is possible. Like other acids, carboxylic acids may initiate polymerization reactions; like other acids, they often catalyze (increase the rate of) chemical reactions.

Fire Hazard

Flash point data for Orotic acid are not available; however, Orotic acid is probably combustible.

Safety Profile

Moderately toxic by ingestion, intraperitoneal, and intravenous routes. Mutation data reported. Whenheated to decomposition it emits toxic fumes of NOx.

InChI:InChI=1/C5H4N2O4/c8-3-1-2(4(9)10)6-5(11)7-3/h1H,(H,9,10)(H2,6,7,8,11)

Synthetic route

6-Methyluracil (626-48-2) → orotic acid (65-86-1)

Conditions	Yield
With 2,2'-azobis(isobutyronitrile); oxygen; cobalt(II) acetate; acetic acid at 80℃; for 15h;	92%
With potassium hydroxide; potassium hexacyanoferrate(III)

2,4-imidazolidinedione (461-72-3) + Glyoxilic acid (298-12-4) → orotic acid (65-86-1)

Conditions	Yield
With sodium hydroxide In water at 115 - 120℃; for 2h; Temperature; Large scale;	91.9%

(2Z)-(2,5-dioxoimidazolidin-4-ylidene)acetic acid (153816-00-3) → orotic acid (65-86-1)

Conditions	Yield
With potassium hydroxide at 64℃; for 3h;	85%
With potassium hydroxide at 64℃; for 3h; Mechanism; Kinetics; var. conc. of KOH;	85%

C5H6N2O4 → orotic acid (65-86-1)

Conditions	Yield
With oxygen; palladium dichloride In N,N-dimethyl-formamide at 80℃; under 760.051 Torr; for 36h; Reagent/catalyst; Solvent; Pressure; Temperature;	85%

glycoluril (496-46-8) + Glyoxal (131543-46-9) → orotic acid (65-86-1)

Conditions	Yield
Stage #1: glycoluril; Glyoxal With sodium hydroxide In water for 8h; Autoclave; Reflux; Large scale; Stage #2: With chlorine at 20℃; Time; Large scale;	33%

orotoaldehyde (36327-91-0) → 6-(hydroxymethyl)pyrimidine-2,4(1H,3H)-dione (22126-44-9) + orotic acid (65-86-1)

Conditions	Yield
With potassium hydroxide

orotoaldehyde (36327-91-0) → orotic acid (65-86-1)

Conditions	Yield
With sodium dichromate; sulfuric acid

6-oxo-2-thioxo-1,2,3,6-tetrahydro-pyrimidine-4-carbaldehyde (16953-46-1) → orotic acid (65-86-1)

Conditions	Yield
With sodium dichromate; sulfuric acid
Multi-step reaction with 2 steps 1: aqueous KOH 2: aqueous alkali .H2O2 View Scheme

2-thioorotic acid (6953-78-2) → orotic acid (65-86-1)

Conditions	Yield
With alkali .H2O2

6-carboxymethyluracil (4628-39-1) → orotic acid (65-86-1)

Conditions	Yield
With potassium hydroxide; potassium hexacyanoferrate(III) 22 d;

2-(methylthio)-6-oxo-1,6-dihydropyrimidine-4-carboxylic acid (6314-14-3) → orotic acid (65-86-1)

Conditions	Yield
With hydrogenchloride

6-diethoxymethyl-1H-pyrimidine-2,4-dione (16953-48-3) → orotic acid (65-86-1)

Conditions	Yield
With sodium dichromate; sulfuric acid
Multi-step reaction with 2 steps 1: Hydrolysis 2: Na2Cr2O7/H2SO4 View Scheme

6-diethoxymethyl-2-thioxo-2,3-dihydro-1H-pyrimidin-4-one (16953-49-4) → orotic acid (65-86-1)

Conditions	Yield
With sodium dichromate; sulfuric acid
Multi-step reaction with 3 steps 1: aqueous H2O2; aqueous NaOH 2: Hydrolysis 3: Na2Cr2O7/H2SO4 View Scheme
Multi-step reaction with 2 steps 1: aqueous H2O2; aqueous NaOH 2: Na2Cr2O7/H2SO4 View Scheme

(2,5-dioxo-imidazolidin-4-yliden)-acetic acid (58668-24-9) → orotic acid (65-86-1)

Conditions	Yield
With potassium hydroxide

2,6-Dioxo-3,6-dihydro-2H-[1,3]oxazine-4-carboxylic acid (119767-58-7) → orotic acid (65-86-1)

Conditions	Yield
With ammonia In various solvent(s)

methyl N1,N3-dibenzyloxymethyl-orotate (80140-18-7) → orotic acid (65-86-1)

Conditions	Yield
With trimethylsilyl iodide; water 1.) chloroform, reflux, 6 h, 2.) reflux, 30 min; 160-180 deg C, 15 min; reflux; Yield given. Multistep reaction;

uracil (66-22-8) → orotic acid (65-86-1) + isoorotidine (489-36-1)

Conditions	Yield
at 37℃; for 72h; Product distribution; strain 556F from Bacillus subtilis, pH 7.2; effect of different amounts of uracil, other mutants of Bacillus subtilis;

L-dihydroorotic acid (5988-19-2) → orotic acid (65-86-1)

Conditions	Yield
With dihydroorotate dehydrogenase; bis(1-chloro-2-propyl) ether; All-Trans Coenzyme Q6; Triton X-100 In water at 37℃; pH=7.8;
With dihydroorotate dehydrogenase In phosphate buffer at 22℃; pH=7; Enzyme kinetics; Further Variations:; also in the presence of detergent;
With human dihydroorotate dehydrogenase; 2,3-dimethoxy-5-methyl-6-(3-methyl-2-butenyl)-1,4-benzoquinone Enzyme kinetics;
With 2,3-Dimethoxy-5-methyl-1,4-benzoquinone; 2,6-Dichlorophenolindophenol; glycerol; sodium chloride; Triton X-100 In water; N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid Microbiological reaction; Enzymatic reaction;
With decylubiquinone; pfDHODH at 25℃; Enzyme kinetics; buffer C;

4.5-dichloro-2.6-dioxo-hexahydropyrimidine-carboxylic acid-(4) → orotic acid (65-86-1)

(2,5-dioxo-imidazolidin-4-yliden)-acetic acid (58668-24-9) + aqueous KOH → orotic acid (65-86-1)

uracil-carboxylic acid-(4)-amide → orotic acid (65-86-1)

Conditions	Yield
With potassium hydroxide

uracil-carboxylic acid-(4)-ethyl ester → orotic acid (65-86-1)

Conditions	Yield
With potassium hydroxide

dialuryldiazoacetic acid ethyl ester → orotic acid (65-86-1) + 5-ethoxycarbonylmethylene-hydantoin

Conditions	Yield
With sodium hydroxide

ureidosuccinic acid (923-37-5, 173298-46-9) → orotic acid (65-86-1)

Conditions	Yield
Multi-step reaction with 3 steps 1: 77 percent / 20percent aq. HCl 2: 71 percent / Br2 / acetic acid / 4 h / 100 °C 3: 85 percent / aq. KOH / 3 h / 64 °C / var. conc. of KOH View Scheme

5-hydantoinacetic acid (5427-26-9) → orotic acid (65-86-1)

Conditions	Yield
Multi-step reaction with 2 steps 1: 71 percent / Br2 / acetic acid / 4 h / 100 °C 2: 85 percent / aq. KOH / 3 h / 64 °C / var. conc. of KOH View Scheme
Multi-step reaction with 2 steps 1: bromine; acetic acid / Beim Erhitzen des Reaktionsprodukts mit H2O 2: aqueous KOH View Scheme

5-fluoro-1H-indole-2,3-dione (443-69-6) + 5-amino-2,6-dioxo-1,2,3,6-tetrahydropyrimidine-4-carboxylic acid (7164-43-4) → orotic acid (65-86-1)

Conditions	Yield
	1.1 g (73%)

cyanomethylurea (5962-07-2) + Glyoxilic acid (298-12-4) → orotic acid (65-86-1)

Conditions	Yield
With sodium hydroxide In methanol; water
With sodium hydroxide for 2h; Reflux; Large scale;

orotidine 5'-monophosphate (2149-82-8) → orotic acid (65-86-1) + 5-phosphoribosyl-1-pyrophosphate (97-55-2, 7540-64-9, 99945-37-6, 130384-52-0)

Conditions	Yield
With Salmonella typhimurium OMP synthase wild type; magnesium chloride at 30℃; pH=8; Kinetics; Reagent/catalyst; aq. phosphate buffer; Enzymatic reaction;

4,5-dihydroorotic acid (155-54-4) → orotic acid (65-86-1)

Conditions	Yield
With dihydroorotate dehydrogenase Enzymatic reaction;
With dihydroorotate dehydrogenase; coenzyme Q0 pH=8; Enzymatic reaction;

chloro-trimethyl-silane (75-77-4) + orotic acid (65-86-1) → 2,6-Bis-trimethylsilanyloxy-pyrimidine-4-carboxylic acid (32865-94-4)

Conditions	Yield
With 1,1,1,3,3,3-hexamethyl-disilazane Ambient temperature;	99%

orotic acid (65-86-1) + sitagliptin (486460-32-6) → sitagliptin orotate (1246343-77-0)

Conditions	Yield
In acetonitrile at 25 - 75℃; Product distribution / selectivity;	99%
In water at 35 - 37℃; for 0.166667h;

orotic acid (65-86-1) + acetyl 2,3-O-isopropylidene-α,β-ribofuranose → 1'-O-acetyl-2',3'-O-isopropylidene-5'-O-orotyl-D-ribofuranoside

Conditions	Yield
Stage #1: orotic acid With 1,1'-carbonyldiimidazole In N,N-dimethyl-formamide at 20℃; for 16h; Stage #2: acetyl 2,3-O-isopropylidene-α,β-ribofuranose With pyridine hydrochloride In acetonitrile at 20℃;	98%

1-(5-(2-fluorophenyl)-1-(pyridin-3-ylsulfonyl)-1H-pyrrole-3-yl)-N-methylmethanamine + orotic acid (65-86-1) → 1-[5-(2-fluorophenyl)-1-(pyridin-3-ylsulfonyl)-1H-pyrrol-3-yl]-N-methylmethanamine orotate

Conditions	Yield
In acetone for 0.5h; Solvent; Reflux;	98%

4-[ethyl(dimethyl)ammonio]butanoate (1293923-09-7) + orotic acid (65-86-1) → 3-carboxy-N-ethyl-N,N-dimethylpropan-1-aminium 2,6-dioxo-1,2,3,6-tetrahydropyrimidine-4-carboxylate (1404369-24-9)

Conditions	Yield
In isopropyl alcohol	97.4%

orotic acid (65-86-1) + tenofovir disoproxil → 9-[2-[(R)[[bis[[isopropoxycarbonyl]oxy]methoxy]phosphinyl]methoxy]propyl]adenine orotate

Conditions	Yield
With triethylamine In water; dimethyl sulfoxide at 20 - 30℃; Temperature; Solvent; Reagent/catalyst;	97%
In methanol; water at 20 - 70℃; Solvent;	85%

orotic acid (65-86-1) + L-carnitine (541-15-1) → L-carnitine oroate

Conditions	Yield
In water; acetone for 5h; Solvent; Reflux;	96%

edoxaban + orotic acid (65-86-1) → N1-(5-chloropyridin-2-yl)-N2-((1S,2R,4S)-4-[(dimethylamino)carbonyl]-2-{[(5-methyl-4,5,6,7-tetrahydrothiazolo[5,4-c]pyridin-2-yl)carbonyl]amino}cyclohexyl)ethanediamide orotinate

Conditions	Yield
In acetonitrile at 60℃; for 5h;	96%
In ethanol at 65℃;	5.5 g

diazomethane (186581-53-3, 908094-01-9) + orotic acid (65-86-1) → 1,3-Dimethyl-2,4-dioxo-1,2,3,4-tetrahydro-pyrimidin-6-carbonsaeuremethylester (4116-39-6)

Conditions	Yield
In methanol; diethyl ether at 0℃;	95%
In methanol Ambient temperature;	93%

AMD070 (558447-26-0) + orotic acid (65-86-1) → (S)-(N'-(1H-benzimidazol-2-ylmethyl)-N'-(5,6,7,8-tetrahydroquinolin-8-yl))-1,4-butanediamine orotate (880549-28-0)

Conditions	Yield
In methanol; water at 20℃; for 1h;	95%

orotic acid (65-86-1) → 5-nitroorotic acid (17687-24-0)

Conditions	Yield
With sulfuric acid; nitric acid at 15 - 48℃; for 6h; Temperature; Cooling with ice;	95%
With sulfuric acid; nitric acid In water at 50 - 55℃; for 3h;	90%
Stage #1: orotic acid With sodium hydroxide In water for 3h; Stage #2: With sulfuric acid; nitric acid In water at 25 - 45℃; Inert atmosphere;	88.6%
With sulfuric acid; nitric acid In water at 50 - 55℃;

orotic acid (65-86-1) → 5-oxo-2,5-dihydro-1H-pyrazole-3-carboxylic acid (37832-55-6)

Conditions	Yield
With hydrazine hydrate In water at 90℃; for 5h; Temperature;	95%

1-O-benzoyl-2,3-O-isopropylidene-D-ribofuranoside + orotic acid (65-86-1) → 1'-O-benzoyl-2',3'-O-isopropylidene-5'-O-orotyl-D-ribofuranoside

Conditions	Yield
Stage #1: orotic acid With 1,1'-carbonyldiimidazole In N,N-dimethyl-formamide at 20℃; for 16h; Stage #2: 1-O-benzoyl-2,3-O-isopropylidene-D-ribofuranoside With pyridine hydrochloride In acetonitrile at 20℃; for 4h;	94%

methanol (67-56-1) + orotic acid (65-86-1) → methyl orotate (6153-44-2)

Conditions	Yield
With thionyl chloride at 0 - 5℃; for 6h; Reflux;	92.9%
With hydrogenchloride for 24h; Fischer esterification; Heating;	91%
With hydrogenchloride	90%

orotic acid (65-86-1) → α-chloroorotic acid (36313-98-1)

Conditions	Yield
Stage #1: orotic acid With iron(III) chloride; acetic anhydride; acetic acid at 90 - 95℃; Stage #2: With sulfuryl dichloride Reagent/catalyst; Temperature; Reflux;	92%
With hydrogenchloride; dihydrogen peroxide

(2S,4E)-N-methyl-5-(5-isopropoxy-3-pyridyl)-4-penten-2-amine (252870-53-4) + orotic acid (65-86-1) → orotic acid salt of (2S)-(4E)-N-methyl-5-[5-isopropoxypyridin-3-yl]-4-penten-2-amine

Conditions	Yield
In ethanol Heating / reflux;	91.4%

1-O-pivaloyl-2,3-O-isopropylidene-D-ribofuranoside + orotic acid (65-86-1) → 1'-O-pivaloyl-2',3'-O-isopropylidene-5'-O-orotyl-D-ribofuranoside

Conditions	Yield
Stage #1: orotic acid With 1,1'-carbonyldiimidazole In N,N-dimethyl-formamide at 20℃; for 16h; Stage #2: 1-O-pivaloyl-2,3-O-isopropylidene-D-ribofuranoside With pyridine hydrochloride In acetonitrile at 20℃;	90%

N-hydroxy-2-(4-(4-phenylbutyl)phenyl)acetamide (342373-13-1) + orotic acid (65-86-1) → N-(2,6-dioxo-1,2,3,6-tetrahydropyrimidine-4-carbonyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide

Conditions	Yield
With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride In N,N-dimethyl-formamide at 20℃;	90%
With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride In N,N-dimethyl-formamide	90%

orotic acid (65-86-1) + bis(tri-n-butyltin)oxide (56-35-9) → C34H62N4O9Sn2

Conditions	Yield
In toluene for 6h; Reflux; Inert atmosphere; Dean-Stark;	90%

ammonium hexafluorophosphate + bis(2,2'-bipyridine)dichlororuthenium(II) dihydrate + orotic acid (65-86-1) → bis(2,2’-bipyridine) orotate ruthenium(II)

Conditions	Yield
Stage #1: bis(2,2'-bipyridine)dichlororuthenium(II) dihydrate; orotic acid In ethanol at 125℃; for 2h; Sealed tube; Microwave irradiation; Stage #2: ammonium hexafluorophosphate In ethanol; water at 20℃;	89%

orotic acid (65-86-1) + ethyl iodide (75-03-6) → ethyl orotate (1747-53-1)

Conditions	Yield
Stage #1: orotic acid With 1,8-diazabicyclo[5.4.0]undec-7-ene In water; N,N-dimethyl-formamide for 0.0833333h; Stage #2: ethyl iodide In water; N,N-dimethyl-formamide at 60℃; for 5h;	88%
Stage #1: orotic acid With 1,8-diazabicyclo[5.4.0]undec-7-ene In N,N-dimethyl-formamide for 0.0833333h; Stage #2: ethyl iodide In N,N-dimethyl-formamide at 60℃; for 5h;	88%

10-ethoxy-6-(methoxymethyl)-8-(morpholinomethyl)-1,2,3,4-tetrahydrobenzo[h][1,6]naphthyridine-5(6H)-one + orotic acid (65-86-1) → 10-ethoxy-8-(morpholinomethyl)-1,2,3,4-tetrahydrobenzo[h][1,6]naphthyridine-5(6H)-one 2,6-dioxo-1,2,3,6-tetrahydropyrimidine-4-carboxylic acid

Conditions	Yield
In ethanol at 90℃; for 3h;	88%

orotic acid (65-86-1) + glycine tert-butyl ester hydrochloride (27532-96-3) → Ort-Gly-O-t-Bu

Conditions	Yield
With 4-methyl-morpholine; N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline In N,N-dimethyl-formamide at 50 - 55℃;	87%

2,3-O-isopropylidene-D-ribofuranose (67814-68-0, 70266-87-4, 76249-50-8, 76249-51-9, 93451-15-1, 4099-88-1) + orotic acid (65-86-1) → 1',5'-O-diorotyl-2',3'-O-isopropylidene-D-ribofuranoside

Conditions	Yield
With pyridine hydrochloride; 1,1'-carbonyldiimidazole In N,N-dimethyl-formamide at 20℃;	87%

orotic acid (65-86-1) + O-desmethylvenlafaxine (93413-62-8) → O-desmethyl-venlafaxine orotate (1174652-08-4)

Conditions	Yield
In diethyl ether; ethanol at 0 - 20℃; Reflux;	85.4%

orotic acid (65-86-1) + ((S)-2-amino-4-methylpentanoyl)-L-leucine methyl ester hydrochloride (6491-83-4, 63889-48-5, 66190-38-3) → orotyl-L-leucyl-L-leucine methyl ester (74019-79-7)

Conditions	Yield
With 4-methyl-morpholine; N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline In N,N-dimethyl-formamide at 50 - 55℃;	85%

furan-2-ylmethanamine (617-89-0) + orotic acid (65-86-1) → N-(furan-2-ylmethyl)-2,6-dioxo-1,2,3,6-tetrahydro-pyrimidine-4-carboxamide (302603-04-9)

Conditions	Yield
for 0.166667h; microwave irradiation;	85%

Upstream product

• 626-48-2 6-Methyluracil 
• 36327-91-0 orotoaldehyde 
• 16953-46-1 6-oxo-2-thioxo-1,2,3,6-tetrahydro-pyrimidine-4-carbaldehyde 
• 6953-78-2 2-thioorotic acid 
• 6314-14-3 2-(methylthio)-6-oxo-1,6-dihydropyrimidine-4-carboxylic acid 
• 16953-48-3 6-diethoxymethyl-1H-pyrimidine-2,4-dione 
• 16953-49-4 6-diethoxymethyl-2-thioxo-2,3-dihydro-1H-pyrimidin-4-one 
• 58668-24-9 (2,5-dioxo-imidazolidin-4-yliden)-acetic acid 
• 5988-19-2 L-dihydroorotic acid 
• 443-69-6 5-fluoro-1H-indole-2,3-dione 
• 7164-43-4 5-amino-2,6-dioxo-1,2,3,6-tetrahydropyrimidine-4-carboxylic acid 
• 5962-07-2 cyanomethylurea 
• 298-12-4 Glyoxilic acid 
• 496-46-8 glycoluril 

Downstream Products

• 6153-44-2 methyl orotate 
• 4156-75-6 furo<3,4-d>pyrimidine-2,4,7(1H,3H,5H)-trione 
• 1747-53-1 ethyl orotate 
• 705-36-2 1-methyl-2,6-dioxo-1,2,3,6-tetrahydro-pyrimidine-4-carboxylic acid 
• 36313-98-1 5-chloroorotic acid 
• 58-97-9 5'-Uridylic Acid 
• 66-22-8 uracil 
• 58-98-0 UDP 
• 63-39-8 UTP 
• 5988-19-2 L-dihydroorotic acid 
• 155-54-4 4,5-dihydroorotic acid 
• 88280-81-3 Orotsaeureoctylester 
• 4116-38-5 1,3-dimethylorotic acid 
• 26830-94-4 2,4-dichloropyrimidine-6-carboxylic acid chloride 

Relevant articles and documents

Preparation method of vitamin B13

The invention provides a preparation method of vitamin B13. The preparation method specifically comprises the following steps: step 1, carrying out ammonolysis reaction on maleic anhydride and urea toprepare an ammonolysis product; and step 2, oxidizing the ammonolysis product prepared in the step 1 under the catalysis of a catalyst to obtain vitamin B13. The method is a novel chemical reaction,and under the condition that liquid bromine is not used, the ammonolysis product of maleic anhydride and urea can be efficiently converted into vitamin B13. The method has the advantages of simple operation, cheap and easily available reagents, greenness, safety, high efficiency and environmental protection, and is suitable for industrial production.

Synthetic method of orotic acid

The invention discloses a synthetic method of orotic acid, belonging to the technical field of chemical synthesis. The synthetic method of orotic acid comprises the following steps: reacting maleylurea with bromine, wherein the bromine is provided by a reaction of sodium bromide and hydrogen peroxide; and after a reaction of the hydrogen peroxide, the sodium bromide and the maleylurea is finished,adding strong alkali, and adding concentrated hydrochloric acid for acidification after the reaction is completed at 62-64 DEG C so as to obtain the orotic acid. According to the method, the hydrogenperoxide is used for oxidizing the sodium bromide, so elemental halogen used in an original process is replaced, and risks are greatly reduced; the method of applying intermediate bromine generated in situ to a reaction is adopted, so the reaction is uniform and mild, yield and product quality are improved, and the complexity of a production process is reduced; the sodium bromide can be recycled,so no hazardous waste is discharged; in the reaction of synthesizing the maleylurea, acetic acid can be distilled out through reduced-pressure distillation, so cyclic utilization of the acetic acid is achieved, and emission is reduced; and meanwhile, due to process improvement, the yield of the orotic acid is increased.

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New synthesis method of orotic acid

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Novel technology with introduced catalyst to optimize synthesis of dipyridamole

The invention discloses a novel technology with an introduced catalyst to optimize the synthesis of dipyridamole, and belongs to the technical field of medical intermediates. According to the technology, in the step of oxidizing a methyl group of 6-methyl uracil into formic acid, a Co(OAc)2/HOAc/AIBN/O2 catalytic system is introduced, and the reaction yield is increased to 90 to 95%. In the step of reducing a nitro group of nitro-orotic acid into an amino group, activated copper powder is taken as the catalyst, the yield is more than 85%; and moreover, the environmental pollution and danger caused by sodium hydrosulfite are avoided. In the step of converting substituted hydroxyl group into substituted chlorine, SOCl12 and N,N-dimethyl formamide are introduced into the reaction system so as to reduce the environment pollution and the difficulty of post treatment. In the reactions of preparing 2,6-dichloro-4,8-bis(piperidine-1-yl)pyrimido[5,4-d]pyrimidine from perchloro pyrimido[5,4-d]pyrimidine, a CuI/PhNO2 catalytic system is introduced into the reaction system, the reaction yield reaches 95%, moreover, the operation is easy, and the treatment is simple. The provided technology increases the yield, reduces the cost, guarantees the safety, saves the energy, and meets the requirements of green reactions and modern chemical production.

Method for synthesizing orotic acid

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Loop residues and catalysis in OMP synthase

Residue-to-alanine mutations and a two-amino acid deletion have been made in the highly conserved catalytic loop (residues 100-109) of Salmonella typhimurium OMP synthase (orotate phosphoribosyltransferase, EC 2.4.2.10). As described previously, the K103A mutant enzyme exhibited a 104-fold decrease in kcat/KM for PRPP; the K100A enzyme suffered a 50-fold decrease. Alanine mutations at His105 and Glu107 produced 40- and 7-fold decreases in kcat/KM, respectively, and E101A, D104A, and G106A were slightly faster than the wild-type (WT) in terms of kcat, with minor effects on kcat/KM. Equilibrium binding of OMP or PRPP in binary complexes was affected little by loop mutation, suggesting that the energetics of ground-state binding have little contribution from the catalytic loop, or that a favorable binding energy is offset by costs of loop reorganization. Pre-steady-state kinetics for mutants showed that K103A and E107A had lost the burst of product formation in each direction that indicated rapid on-enzyme chemistry for WT, but that the burst was retained by H105A. Δ102Δ106, a loop-shortened enzyme with Ala102 and Gly106 deleted, showed a 104-fold reduction of kcat but almost unaltered KD values for all four substrate molecules. The 20% (i.e., 1.20) intrinsic [1′-3H]OMP kinetic isotope effect (KIE) for WT is masked because of high forward and reverse commitment factors. K103A failed to express intrinsic KIEs fully (1.095 ± 0.013). In contrast, H105A, which has a smaller catalytic lesion, gave a [1′-3H]OMP KIE of 1.21 ± 0.0005, and E107A (1.179 ± 0.0049) also gave high values. These results are interpreted in the context of the X-ray structure of the complete substrate complex for the enzyme [Grubmeyer, C., Hansen, M. R., Fedorov, A. A., and Almo, S. C. (2012) Biochemistry 51 (preceding paper in this issue, DOI 10.1021/bi300083p)]. The full expression of KIEs by H105A and E107A may result from a less secure closure of the catalytic loop. The lower level of expression of the KIE by K103A suggests that in these mutant proteins the major barrier to catalysis is successful closure of the catalytic loop, which when closed, produces rapid and reversible catalysis. (Graph Presented).

CGRP ANTAGONISTS

The present invention relates to new CGRP-antagonists of general formula I wherein U, V, X, Y, R1, R2 and R3 are defined as stated hereinafter, the tautomers, the isomers, the diastereomers, the enantiomers, the hydrates, the mixtures thereof and the salts thereof and the hydrates of the salts, particularly the physiologically acceptable salts thereof with inorganic or organic acids or bases, pharmaceutical compositions containing these compounds, their use and processes for preparing them.