Tag: M.W=150-200

Kang, Yanlong published the artcileHeat Shock Protein 70 Inhibitors. 1. 2,5′-Thiodipyrimidine and 5-(Phenylthio)pyrimidine Acrylamides as Irreversible Binders to an Allosteric Site on Heat Shock Protein 70, Related Products of pyrimidines, the publication is Journal of Medicinal Chemistry (2014), 57(4), 1188-1207, database is CAplus and MEDLINE.

Heat shock protein 70 (Hsp70) is an important emerging cancer target whose inhibition may affect multiple cancer-associated signaling pathways and, moreover, result in significant cancer cell apoptosis. Despite considerable interest from both academia and pharmaceutical companies in the discovery and development of druglike Hsp70 inhibitors, little success has been reported so far. Here we describe structure-activity relationship studies in the first rationally designed Hsp70 inhibitor class that binds to a novel allosteric pocket located in the N-terminal domain of the protein. These 2,5′-thiodipyrimidine and 5-(phenylthio)pyrimidine acrylamides take advantage of an active cysteine embedded in the allosteric pocket to act as covalent protein modifiers upon binding. The study identifies derivatives 17a and 20a, which selectively bind to Hsp70 in cancer cells. Addition of high nanomolar to low micromolar concentrations of these inhibitors to cancer cells leads to a reduction in the steady-state levels of Hsp70-sheltered oncoproteins, an effect associated with inhibition of cancer cell growth and apoptosis. In summary, the described scaffolds represent a viable starting point for the development of druglike Hsp70 inhibitors as novel anticancer therapeutics.

Journal of Medicinal Chemistry published new progress about 56-05-3. 56-05-3 belongs to pyrimidines, auxiliary class Pyrimidine,Chloride,Amine,API, name is 2-Amino-4,6-dichloropyrimidine, and the molecular formula is C4H3Cl2N3, Related Products of pyrimidines.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Meduna, Steven P. published the artcileTriamino pyrimidines and pyridines as histamine H₄ receptor modulators, Recommanded Product: 2-Amino-4,6-dichloropyrimidine, the publication is Bioorganic & Medicinal Chemistry Letters (2011), 21(10), 3113-3116, database is CAplus and MEDLINE.

Two series of triamino pyrimidines and a series of triamino pyridines have been synthesized and their structure-activity relationships evaluated for activity at the H₄ receptor in competitive binding and functional assays. Small structural changes in these three hetereoarom. cores influenced the functional activity of these compounds

Bioorganic & Medicinal Chemistry Letters published new progress about 56-05-3. 56-05-3 belongs to pyrimidines, auxiliary class Pyrimidine,Chloride,Amine,API, name is 2-Amino-4,6-dichloropyrimidine, and the molecular formula is C4H3Cl2N3, Recommanded Product: 2-Amino-4,6-dichloropyrimidine.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Bold, Guido published the artcileA Novel Potent Oral Series of VEGFR2 Inhibitors Abrogate Tumor Growth by Inhibiting Angiogenesis, Synthetic Route of 56-05-3, the publication is Journal of Medicinal Chemistry (2016), 59(1), 132-146, database is CAplus and MEDLINE.

This paper describes the identification of 6-(pyrimidin-4-yloxy)-naphthalene-1-carboxamides as a new class of potent and selective human vascular endothelial growth factor receptor 2 (VEGFR2) tyrosine kinase inhibitors. In biochem. and cellular assays, the compounds exhibit single-digit nanomolar potency toward VEGFR2. Compounds of this series show good exposure in rodents when dosed orally. They potently inhibit VEGF-driven angiogenesis in a chamber model and rodent tumor models at daily doses of less than 3 mg/kg by targeting the tumor vasculature as demonstrated by ELISA for TIE-2 in lysates or by immunohistochem. anal. This novel series of compounds shows a potential for the treatment of solid tumors and other diseases where angiogenesis plays an important role.

Journal of Medicinal Chemistry published new progress about 56-05-3. 56-05-3 belongs to pyrimidines, auxiliary class Pyrimidine,Chloride,Amine,API, name is 2-Amino-4,6-dichloropyrimidine, and the molecular formula is C4H3Cl2N3, Synthetic Route of 56-05-3.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Engelhardt, Harald published the artcileBispyrimidines as Potent Histamine H₄ Receptor Ligands: Delineation of Structure-Activity Relationships and Detailed H₄ Receptor Binding Mode, Product Details of C4H3Cl2N3, the publication is Journal of Medicinal Chemistry (2013), 56(11), 4264-4276, database is CAplus and MEDLINE.

The basic methylpiperazine moiety is considered a necessary substructure for high histamine H₄ receptor (H₄R) affinity. This moiety is however also the metabolic hot spot for various classes of H₄R ligands (e.g., indolcarboxamides and pyrimidines). We set out to investigate whether mildly basic 2-aminopyrimidines in combination with the appropriate linker can serve as a replacement for the methylpiperazine moiety. In the series of 2-aminopyrimidines, the introduction of an addnl. 2-aminopyrimidine moiety in combination with the appropriate linker lead to bispyrimidines displaying pK_i values for binding the human H₄R up to 8.2. Furthermore, the methylpiperazine replacement results in compounds with improved metabolic properties. The attempt to transfer the knowledge generated in the class of bispyrimidines to the indolecarboxamides failed. Combining the derived structure-activity relationships with homol. modeling leads to new detailed insights in the mol. aspects of ligand-H₄R binding in general and the binding mode of the described bispyrimidines in specific.

Journal of Medicinal Chemistry published new progress about 56-05-3. 56-05-3 belongs to pyrimidines, auxiliary class Pyrimidine,Chloride,Amine,API, name is 2-Amino-4,6-dichloropyrimidine, and the molecular formula is C4H3Cl2N3, Product Details of C4H3Cl2N3.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Hasanein, Ahmed A. published the artcileDFT calculations of amine-imine tautomerism in some pyrimidine derivatives and their 1:1 and 1:2 complexes with water, Category: pyrimidines, the publication is International Journal of Quantum Chemistry (2011), 111(15), 3993-4010, database is CAplus.

Amine-Imine tautomerization in 2-amino-pyrimidine (I), 2-amino-4,6-dichloropyrimidine (II), 2-amino-4,6-dimethylpyrimidine (III), and 2-amino-4,6-dimethoxypyrimidine (IV) and their 1:1 and 1:2 H-bonded complexes with water have been studied using the B3LYP/6-31++G** method. Optimum mol. geometries, electronic properties, and energetics of these systems have been discussed. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011.

International Journal of Quantum Chemistry published new progress about 56-05-3. 56-05-3 belongs to pyrimidines, auxiliary class Pyrimidine,Chloride,Amine,API, name is 2-Amino-4,6-dichloropyrimidine, and the molecular formula is C4H3Cl2N3, Category: pyrimidines.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Yuan, Libo published the artcileChemical labeling of 5-iodo-2′-deoxyuridine with 4-ethynyl-N-ethyl-1,8-naphthalimide using copper-free Sonogashira cross-coupling in aqueous medium, Computed Properties of 5738-14-7, the publication is Synthetic Communications (2014), 44(7), 1007-1011, database is CAplus.

The synthesis of a fluorescent nucleoside analog was reported by using a Cu-free Sonogashira cross-coupling reaction in a satisfactory yield. This reaction occurred at 37° in open air and aqueous medium and avoided the toxicity of Cu(I). The mild Sonogashira reaction provided the possibility of fluorescent labeling of nucleoside mimics in living cells.

Synthetic Communications published new progress about 5738-14-7. 5738-14-7 belongs to pyrimidines, auxiliary class Pyrimidine,Amine,Alcohol,Pyrimidine, name is 2-(Dimethylamino)pyrimidine-4,6-diol, and the molecular formula is C8H8O3, Computed Properties of 5738-14-7.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Zheng, Wen-Na published the artcileSynthesis, crystal structure, herbicide safening, and antifungal activity of N-(4,6-dichloropyrimidine-2-yl)benzamide, Application In Synthesis of 56-05-3, the publication is Crystals (2018), 8(2), 75/1-75/10, database is CAplus.

The compound N-(4,6-dichloropyrimidine-2-yl)benzamide (C₁₁H₇Cl₂N₃O) was synthesized and the corresponding structure was confirmed by ¹H NMR, ¹³C NMR, HRMS, IR, and single-crystal X-ray diffraction. The compound crystallized in a monoclinic system with space group P 2₁/c, where a = 14.9156(6), b = 16.6291(8), c = 14.4740(6) Å, β = 95.160(2)°, V = 3575.5(3) ų, Z = 12, Dc = 1.494 g·cm^-3, F(000) = 1632, μ(MoKa) = 3.182 mm^-1, final R = 0.0870, and wR = 0.2331 with I > 2σ(I). The crystal structure was found to be stabilized by intermol. hydrogen bonding interactions N-H···O and C-H···Cl. Furthermore, the results from biol. assays indicated that the compound showed a similar protective effect on metolachlor injury in rice seedlings compared to fenclorim at a concentration of 4.0 mg·L^-1. Moreover, the compound exhibited an improved antifungal activity compared to pyrimethanil against S. sclerotiorum and F. oxysporum. Potentially, these results lay the foundation for the development of novel herbicide safeners and fungicides.

Crystals published new progress about 56-05-3. 56-05-3 belongs to pyrimidines, auxiliary class Pyrimidine,Chloride,Amine,API, name is 2-Amino-4,6-dichloropyrimidine, and the molecular formula is C12H10F2Si, Application In Synthesis of 56-05-3.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Boon, W. R. published the artcilePteridines. IV. Derivatives of 2,4-diaminopteridine and related compounds, Formula: C6H9N3O2, the publication is Journal of the Chemical Society (1957), 2146-58, database is CAplus.

cf. C.A. 46, 2082g. Several derivatives of 2,4-(H₂N)₂-Y (in this abstract Y = pteridine) possess antimalarial activity (Potter and Henshall, C.A. 51, 1974h). A series of 2,4,6,7-(H₂N)₂Ph₂-Y were prepared in which the H₂N groups were progressively substituted by Me. Antimalarial activity was immediately lost, but the compounds were active against exptl. schistosomiasis in mice. Further modifications of the substituents always lowered the activity. Only a few compounds showed any appreciable activity. 2,4,6-Me₂N-(HO)₂-Z (in this abstract Z = pyrimidine) ground to pass a 30-mesh sieve, added with stirring during 45 min. to 280 cc. AcOH and 65 cc. HNO₃ (d. 1.5) at 20-5°, stirred an addnl. 45 min., the mixture poured into 1350 cc. H₂O, the solid separated, washed free from acid, and dried gave 81 g. 5-O₂N derivative (I). I (5 g.), 60 cc. POCl₃, and 20 cc. PhNMe₂ heated to 105° (bath temperature), after the vigorous reaction the heating continued 1 hr., excess POCl₃ removed in vacuo, the residue treated with 200 g. ice, the suspension extracted with four 50-cc. portions of Et₂O, the combined extracts dried, filtered, evaporated, and the residue crystallized from petr. ether (b. 60-80°) gave 3.7 g. 4,6-Cl₂ compound (II), m. 117-20°. II (14 g.), 90 cc. C₆H₆, and 10 cc. aqueous NH₃ (d. 0.880) shaken overnight, the mixture filtered, and the residue (4.2 g.) crystallized twice from dioxane gave the 4,6-(H₂N)₂ compound, m. 249-50°; evaporation of the filtrate gave a residue which, after chromatography on 120 g. Al₂O₃ in 30 cc. C₆H₆ and crystallization from EtOAc-petr. ether afforded 0.5 g. 4-H₂N compound, m. 132°. To 91 g. Na in 2 l. MeOH was added 509 g. [MeHNC(:NH)NH₂]₂.H₂SO₄, the mixture refluxed 30 min. with stirring, CH₂(CO₂Et)₂ added, the heating continued 6 hrs., the mixture cooled, diluted with 5 l. H₂O, treated with C, filtered, the filtrate acidified to litmus with AcOH, and the precipitate collected to give 183 g. 2,4,6-MeHN(HO)₂-Z (III); the mother liquors deposited 15 g. presumably 2-amino-1,4,5,6-tetrahydro-1-methyl-4,6-dioxo-Z, m. above 360°. III (93g.) and 510 g. POCl₃ refluxed 1 hr., the mixture filtered through sintered glass, the filtrate poured on 2250 cc. 32% aqueous NaOH and ice, the separated solid collected, washed with H₂O, and crystallized from MeOH gave 88 g. 2,4,6-(MeHN)Cl₂-Z (IV), m. 164°. IV (130 g.) heated 12 hrs. with NaOMe (from 168 g. Na in 570 cc. MeOH), the solution cooled, the precipitate collected, washed with H₂O, and crystallized from MeOH yielded 95 g. 4,6,2-Cl(MeO)(MeHN)-Z, m. 153°. Similarly was prepared 81% 4,6,2-Cl(MeO)(Me₂N)-Z (VI), m. 62° (after sublimation at 55°/0.1 mm.), from 4,6,2-Cl₂(Me₂N)-Z at room temperature VI (10 g.) heated 30 min. on a steam bath with 50 cc. HCl, the solution cooled, the product collected, and purified by solution in aqueous alkali, treatment with C, and reprecipitation with AcOH gave 5.5 g. 6-HO compound, m. 265° (decomposition). Similarly was obtained from VI 95% 4,6,2-Cl(HO)(Me₂N)-Z (VII), m. 217°. 4,6,2-ClMe(H₂N)-Z (28.7 g.) and 78 cc. 19.5% alc. Me₂NH heated 17 hrs. at 110-20° gave 172 g. 4-Me₂N derivative, m. 172° (from C₆H₆). Ph(H₂N)CHCOPh.HCl (47 g.) dissolved in 750 cc. H₂O. basified at 0° with aqueous NH₃, the base collected, sucked as dry as possible, added to 35 g. 2,4,6-Cl₃-Z (VIII) in 750 cc. EtOH, the mixture set aside 2 days at room temperature, the precipitate (12 g.) collected, and crystallized from EtOH gave α-(2,4-dichloro-6-pyrimidylamino)deoxybenzoin (IX), m. 165°. p-ClC₆H₄CHBzNH₂ (X) (28.5 g.) converted to the base, the latter treated as above with 9 g. VIII, the crude product refluxed 3 hrs. with 10 cc. 19.5% alc. Me₂NH and 10 cc. EtOH, the solution evaporated to 0.5 its volume, and the solid recrystallized from MeOH gave ω-(4-chloro-2-dimethylamino-6-pyrimidyl-amino)-ω-(p-chlorophenyl)acetophenone, m. 151-2°; the mother liquors gave the 6-Me₂N isomer, m. 181-2° (from EtOH), and a small amount of another compound believed to be 2,5-di(p-chlorophenyl)-3,6-diphenylpyrazine, m. 239-40°. 4,6,2-Cl₂(H₂N)-Z (XI) (33 g.) heated 3 hrs. with 175 cc. 19.5% alc. Me₂NH, after the initial reaction had subsided the solution cooled, the precipitate (24 g.) collected, and crystallized from MeOH and then from C₆H₆ gave 4,2,6-Cl(H₂N)(Me₂N)-Z, m. 164-5°. Similarly were obtained in 70% yield from the appropriate derivative of XI and an alc. solution of H₂NCH₂CO₂Et, Et 4-chloro-2-methylamino-6-pyrimidylaminoacetate (XII), m. 167°, and Et 4-chloro-2-dimethylamino-6-pyrimidylamino-acetate, m. 121°. 2,4,6-Cl₂(Me₂N)-Z (36 g.), 200 cc. EtOH, and 50 cc. 70% aqueous EtNH₂ refluxed 6 hrs., EtOH removed, the mixture diluted with H₂O, extracted with Et₂O, the extract dried, Et₂O removed, the residue dissolved in 70 cc. absolute EtOH, 9 cc. concentrated H₂SO₄ added (the mixture acid to Congo red), and dry Et₂O added to a permanent turbidity gave 34 g. 4,6,2-Cl(EtNH)(MeNH)-Z sulfate, m. 148° (from EtOH-Et₂O). The following compounds were prepared similarly: 4,2,6-Cl(Me₂N)(MeNH)-Z, m. 78° (from petr. ether); 4,2,6-Cl(Et₂N)(MeNH)-Z sulfate, m. 148-9° (from EtOH-Et₂O); 4-chloro-6-methylamino-2-piperidino-Z, m. 118° (from MeOH); 4,6,2-Cl(MeNH)(Me₂NCH₂CH₂NH)-Z, m. 99° (from EtOAc-petr. ether). To 17.5 g. VII in 500 cc. H₂O containing 60 cc. 2N NaOH and 12.6 g. NaHCO₃ was added 4-ClC₆H₄N₂Cl (XIII) [from 12.75 g. 4-ClC₆H₄NH₂ (XIV)], the solution stirred overnight, the precipitate collected, washed with H₂O, EtOH, and Et₂O, and crystallized from dioxane to give 20 g. 5-p-ClC₆H₄N₂ derivative (XV), m. 220-2° (decomposition). 4,6,2,5-Cl(HO)(MeNH)(p-ClC₆H₄N₂)-Z was obtained similarly but could not be purified without decomposition XIII (500 cc. 0.025M) and 46 g. NaOAc.3H₂O (XVI) added with stirring to 3.8 g. 6,4,2-Me(HO)(Me₂N)-Z in 500 cc. H₂O, after 16 hrs. the precipitate collected, washed, dried in air, and recrystallized from BuOH gave 5.5 g. 5-(p-ClC₆H₄N₂) derivative, m. 216-17°. XIII (50 cc. 0.025M) and 40 g. XVI added with stirring to 5.0 g. 4,2,6-Cl(Me₂N)₂-Z in 70 cc. AcOH, diluted with 200 cc. H₂O, after 48 hrs. stirring the solid collected, washed with H₂O, and crystallized twice from EtOH gave 5 g. 5-(p-ClC₆H₄N₂) derivative (XVII), m. 91°. The following N.CX:N.CW:C(N:NR).CY (XVIII) (W = Cl) were prepared (X, Y, R, m.p., crystallization solvent, % yield given): NH₂, NHMe, p-ClC₆H₄, 255°, HCONMe (XIX), 47; NH₂, NMe₂, p-ClC₆H₄, 204°, XIX-EtOH, 65; NHMe, NH₂, p-ClC₆H₄, 272° (decomposition), XIX, 90; NHMe, NHMe, p-ClC₆H₄, 272°, XIX-EtOH, 95; NHEt, NHMe, p-ClC₆H₄, 214°, BuOH, 75; NMe₂, NH₂, p-ClC₆H₄, 229°, BuOH, 90; NMe₂, NHMe, Ph, 163°, EtOH, 78; NMe₂, NHMe, p-ClC₆H₄, 183°, BuOH, 90; HNCH₂CH₂NMe₂, NHMe, p-ClC₆H₄, 158°, EtOH, 50. 6,4,2,5-Cl(H₂N)(Me₂N)(p-ClC₆ H₄N₂)-Z (XX) (2 g.) and 40 cc. saturated alc. NH₃ heated 36 hrs. at 150-60°, the solution cooled, and the product (1.75 g.) crystallized from BuOH gave 6-H₂N compound, m. 272-3° [HCl salt, m. 301° (decomposition) (from 80% HCO₂H) (prepared from XIII and 4,6,2-(H₂N)₂(Me₂N)-Z in AcOH)]. Similarly were prepared the following XVIII (W = NH₂, R = p-ClC₆H₄) (X, Y, m.p., crystallization solvent, % yield given): NH₂, NHMe, 213°, BuOH, 40 and 80; NH₂, NMe₂, 205°, XIX-H₂O, 96; NH₂,

Journal of the Chemical Society published new progress about 5738-14-7. 5738-14-7 belongs to pyrimidines, auxiliary class Pyrimidine,Amine,Alcohol,Pyrimidine, name is 2-(Dimethylamino)pyrimidine-4,6-diol, and the molecular formula is C6H9N3O2, Formula: C6H9N3O2.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Boon, W. R. published the artcile4,6-Dichloro-2-dimethylaminopyrimidine, Quality Control of 5738-14-7, the publication is Journal of the Chemical Society (1952), 1532, database is CAplus.

Me₂NC(:NH)NH₂.0.5H₂SO₄ (91 g.), stirred 30 min. with 300 cc. boiling MeOH containing 15 g. Na, the solution treated with 116 g. CH₂(CO₂Et)₂, refluxed 6 hrs., diluted with 450 cc. H₂O, and acidified with AcOH, gives 85 g. 2-dimethylamino-4,6-dihydroxypyrimidine (I), with 3 mols. H₂O, does not m. at 350°. I (15.5 g.) and 60 cc.POCl₃, refluxed 35 min. and poured into 1 l. cold 2 N NaOH, give 16 g. 4,6-dichloro-2-dimethylaminopyrimidine (II), m. 54°; II also results from the reaction of 2,4,6-tri-chloropyrimidine and Me₂NH on crystallization from petr. ether and aqueous MeOH (cf. King and King, C.A. 42, 1280h). I (3.8 g.) and 10 cc. 10% EtOH-NH₃, heated 18 hrs. at 110-20°, give 4-amino-6-chloro-2-dimethylaminopyrimidine, m. 151°; this results also from 4-amino-2,6-dichloropyrimidine and Me₂NH (10 hrs. at 80°). I and EtOH-MeNH₂ or 2,4-dichloro-6-methylaminopyrimidine and alc. Me₂NH give 4-chloro-2-dimethylamino-6-aminopyrimidine, b₁ 122-5°. Il and EtOH-Me₂NH give 4-chloro-2,6-bis(dimethylamino)-pyrimidine, m. 52.2°, sublimes 56°/0.1 mm.

Journal of the Chemical Society published new progress about 5738-14-7. 5738-14-7 belongs to pyrimidines, auxiliary class Pyrimidine,Amine,Alcohol,Pyrimidine, name is 2-(Dimethylamino)pyrimidine-4,6-diol, and the molecular formula is C6H9N3O2, Quality Control of 5738-14-7.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Xuan, G. S. published the artcileInhibition of carbonic anhydrase II by sulfonamide derivatives, SDS of cas: 56-05-3, the publication is Pharmazie (2021), 76(9), 412-415, database is CAplus and MEDLINE.

A series of sulfonamide derivatives I [R = NH₂, ethoxycarbonylazanyl, (pyrimidin-2-yl)aminyl, 3-methyl-5-phenyl-1H-pyrazol-1-yl, etc.; R¹ = H, C(O)CH₃] were synthesized, and the enzyme inhibitory activity of the synthesized compounds I on carbonic anhydrase II was evaluated. Through mol. docking studies, it was found that compounds I [R = NHNH₂, R¹ = C(O)CH₃; R = (pyrimidin-2-yl)aminyl, R¹ = C(O)CH₃ (II); R = acetamidyl, R¹ = C(O)CH₃; R = ethoxycarbonylazanyl, R¹ = C(O)CH₃ (III); R = 3,5-dimethyl-1H-pyrazol-1-yl, R¹ = H (IV)] have a strong binding affinity to carbonic anhydrase II. The IC₅₀ values of the four compounds II, III, IV and I (R = 3-methyl-5-phenyl-1H-pyrazol-1-yl; R¹ = H) were lower than that of the pos. control drug acetazolamide. What’s more, the compounds had a high inhibitory activity for A549 lung cancer cell growth, among them, II and IV could inhibit both carbonic anhydrase II and lung cancer cell proliferation.

Pharmazie published new progress about 56-05-3. 56-05-3 belongs to pyrimidines, auxiliary class Pyrimidine,Chloride,Amine,API, name is 2-Amino-4,6-dichloropyrimidine, and the molecular formula is C24H12, SDS of cas: 56-05-3.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia