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Journal articles on the topic '5-a]pyrimidines'

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Published: 4 June 2021

Last updated: 1 February 2022

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1

Elnagdi, Mohamed Hilmy, Nadia Hassen Taha, Fatma Abdel Maksoud Abd El All, Ramadan Maawad Abdel-Motaleb, and Fivian Farouk Mahmoud. "Studies on condensed pyrazoles: Synthesis of new methyl and amino pyrazolo[1,5-a]pyrimidines and of pyrazolo[5,1-c][1,2,4]triazines." Collection of Czechoslovak Chemical Communications 54, no. 4 (1989): 1082–91. http://dx.doi.org/10.1135/cccc19891082.

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A variety of 3-arylazo 5-amino and 7-aminopyrazolo[1,5-a]pyrimidines were obtained via reacting Ia-Id with cinnamonitriles. The structure of products was confirmed via 1H NMR. Both 5-amino- and 7-amino-3-arylazo pyrazolo[1,5-a]pyrimidines reacted, with protons in acetic acid-sulphuric acid mixture to yield the corresponding 3-unsubstituted acetylaminopyrazolo[1,5-a]pyrimidines. Diazotized Ia and Ib coupled with a variety of active methylene reagents to yield pyrazolo[5,1-c][1,2,4]triazines.

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2

Andrade, Valquiria, Mateus Mittersteiner, Helio Bonacorso, Clarissa Frizzo, Marcos Martins та Nilo Zanatta. "Regioselective Synthesis of 5-(Trifluoromethyl)[1,2,4]triazolo[1,5-a]pyrimidines from β-Enamino Diketones". Synthesis 51, № 11 (2019): 2311–17. http://dx.doi.org/10.1055/s-0037-1611765.

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The use of β-enamino diketones as an easy entry to the regioselective synthesis of [1,2,4]triazolo[1,5-a]pyrimidines is reported. These ketones reacted with 3-amino-1H-1,2,4-triazoles to furnish exclusively 6-substituted 5-(trifluoromethyl)[1,2,4]triazolo[1,5-a]pyrimidines in yields of up to 95%. The regioselectivity of the reactions performed was maintained regardless of the substituent in the starting ketone or aminoazole.

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3

Behera, Manoranjan, M. Sambaiah, Poosa Mallesham, et al. "Tandem Schiff-Base Formation/Heterocyclization: An Approach to the Synthesis of Fused Pyrazolo–Pyrimidine/Isoxazolo-Pyrimidine Hybrids." Synlett 30, no. 05 (2019): 586–92. http://dx.doi.org/10.1055/s-0037-1612081.

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A new synthesis of pyrazolo[4,3-d]pyrimidines and isoxazolo[4,5-d]pyrimidines is described. Key steps in the synthesis involve Stille coupling of 4,6-dichloro-2-phenyl-pyrimidine with tributyl(1-ethoxyvinyl)stannane and tandem Schiff-base formation/heterocyclization of 2,6-di-aryl-5-fluoro-4-acetylpyrimidine with hydrazines or hydroxylamine to give pyrazolo[4,3-d]pyrimidines and isoxazolo[4,5-d]pyrimidines, respectively. The position of the fluoro group in the pyrimidine ring is important for the success of heterocylization reaction.

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4

Chebanov, Valentin A., Vyacheslav E. Saraev, Ekaterina A. Gura, Sergey M. Desenko та Vladimir I. Musatov. "Some Aspects of Reaction of 6-Aminouracil and 6-Amino-2-Thiouracil with α,β-Unsaturated Ketones". Collection of Czechoslovak Chemical Communications 70, № 3 (2005): 350–60. http://dx.doi.org/10.1135/cccc20050350.

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A number of 5,7-diaryl-5,8-dihydropyrido[2,3-d]pyrimidines and 5,7-diarylpyrido[2,3-d]- pyrimidines were obtained by the reaction of 6-aminouracil derivatives with α,β-unsaturated ketones. Basic catalysts decrease yields of the dihydro derivatives whereas acids increase it. In the reactions of ketones containing the dimethylamino group, elimination of the aryl substituent from position 5 of the pyridopyrimidine system was observed. Some aspects of oxidation of 5,8-dihydropyrido[2,3-d]pyrimidines and synthesis of pyrido[2,3-d]pyrimidines were also investigated.

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5

Wilding, Birgit, Stefan Faschauner, and Norbert Klempier. "A practical synthesis of 5-functionalized thieno[2,3-d]pyrimidines." Tetrahedron Letters 56, no. 30 (2015): 4486–89. http://dx.doi.org/10.1016/j.tetlet.2015.05.104.

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6

Gein, V. L., A. N. Prudnikova, A. A. Kurbatova, and M. V. Dmitriev. "Synthesis of (E)-5-Arylvinyl-7-methyltetrazolo[1,5-a]pyrimidines." Russian Journal of General Chemistry 91, no. 4 (2021): 621–25. http://dx.doi.org/10.1134/s1070363221040071.

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Abstract A three-component reaction of 5-aminotetrazole with aromatic aldehydes and acetylacetone under solvent- and catalyst-free conditions at a temperature of 150–160°С proceeds with the formation of (E)-5-arylvinyl-7-methyltetrazolo[1,5-a]pyrimidines. 5,7-Dimethyltetrazolo[1,5-a]pyrimidine is formed as a side-product of the reaction.

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7

Kundu, Nitya G., Biswajit Das, and Anjali Majumdar. "Synthesis of 2,4-Dimethoxy-5-(3-oxo-1-alkynyl)pyrimidines, 2,4-Dimethoxy-5-(3-oxoalkyl)pyrimidines, and 5-(3-Oxoalkyl)uracils by a Highly Convenient Procedure." Synthesis 1990, no. 03 (1990): 243–45. http://dx.doi.org/10.1055/s-1990-26843.

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8

Massari, Serena, Jenny Desantis, Giulio Nannetti, et al. "Efficient and regioselective one-step synthesis of 7-aryl-5-methyl- and 5-aryl-7-methyl-2-amino-[1,2,4]triazolo[1,5-a]pyrimidine derivatives." Organic & Biomolecular Chemistry 15, no. 37 (2017): 7944–55. http://dx.doi.org/10.1039/c7ob02085f.

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9

Kokorekin, Vladimir A., Sergey V. Neverov, Vera N. Kuzina, and Vladimir A. Petrosyan. "A New Method for the Synthesis of 3-Thiocyanatopyrazolo[1,5-a]pyrimidines." Molecules 25, no. 18 (2020): 4169. http://dx.doi.org/10.3390/molecules25184169.

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In this article, we demonstrate how an original effective “metal-free” and “chromatography-free” route for the synthesis of 3-thiocyanatopyrazolo[1,5-a]pyrimidines has been developed. It is based on electrooxidative (anodic) C–H thiocyanation of 5-aminopyrazoles by thiocyanate ion leading to 4-thiocyanato-5-aminopyrazoles (stage 1, yields up to 87%) following by their chemical condensation with 1,3-dicarbonyl compounds or their derivatives (stage 2, yields up to 96%). This method is equally effective for the synthesis of 3-thiocyanatopyrazolo[1,5-a]pyrimidines, both without substituents and wi

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10

Nerkar, A. G., S. A. Ghone, and A. K. Thaker. "In SilicoScreening of the Library of Pyrimidine Derivatives as Thymidylate Synthase Inhibitors for Anticancer Activity." E-Journal of Chemistry 6, no. 3 (2009): 665–72. http://dx.doi.org/10.1155/2009/352717.

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We here report the virtual screening of several series of pyrimidine derivatives forin silicoThymidylate Synthase (TS) inhibition to arrive at possible potential inhibitors of TS with acceptable pharmacokinetic or ADME (Absorption, Distribution, Metabolism and Excretion) properties. Library of the molecules was constructed based upon structural modifications of pyrimidines nucleus. Structural modifications in descending order were performed for the series of pyrimidines,vizfrom pyrimidines with five membered heterocyclic ring to pyrimidines with four membered heterocyclic ring to simple pyrimi

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11

Scapin, Elisandra, Paulo R. S. Salbego, Caroline R. Bender, et al. "Synthesis, effect of substituents on the regiochemistry and equilibrium studies of tetrazolo[1,5-a]pyrimidine/2-azidopyrimidines." Beilstein Journal of Organic Chemistry 13 (November 10, 2017): 2396–407. http://dx.doi.org/10.3762/bjoc.13.237.

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An efficient synthesis methodology for a series of tetrazolo[1,5-a]pyrimidines substituted at the 5- and 7-positions from the cyclocondensation reaction [CCC + NCN] was developed. The NCN corresponds to 5-aminotetrazole and CCC to β-enaminone. Two distinct products were observed in accordance with the β-enaminone substituent. When observed in solution, the compounds can be divided into two groups: (a) precursor compounds with R = CF3 or CCl3, which leads to tetrazolo[1,5-a]pyrimidines in high regioselectivity with R at the 7-position of the heterocyclic ring; and (b) precursor compounds with R

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12

Liebscher, Jürgen, та Lunxiang Yin. "ω-Functionalized 3-Alkynylpyrazolo[1, 5-a]pyrimidines by Sonogashira Coupling". Synthesis 2005, № 01 (2004): 131–35. http://dx.doi.org/10.1055/s-2004-834923.

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13

Nwachukwu, Chideraa I., Leanna J. Patton, Nathan P. Bowling, and Eric Bosch. "Ditopic halogen bonding with bipyrimidines and activated pyrimidines." Acta Crystallographica Section C Structural Chemistry 76, no. 5 (2020): 458–67. http://dx.doi.org/10.1107/s2053229620005082.

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The potential of pyrimidines to serve as ditopic halogen-bond acceptors is explored. The halogen-bonded cocrystals formed from solutions of either 5,5′-bipyrimidine (C8H6N4) or 1,2-bis(pyrimidin-5-yl)ethyne (C10H6N4) and 2 molar equivalents of 1,3-diiodotetrafluorobenzene (C6F4I2) have a 1:1 composition. Each pyrimidine moiety acts as a single halogen-bond acceptor and the bipyrimidines act as ditopic halogen-bond acceptors. In contrast, the activated pyrimidines 2- and 5-{[4-(dimethylamino)phenyl]ethynyl}pyrimidine (C14H13N3) are ditopic halogen-bond acceptors, and 1:1 halogen-bonded cocrysta

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14

Ho, Yuh-Wen. "5-(1-Pyrrolyl)-2-Phenylthieno[2,3-d]Pyrimidine as Building Block in Heterocyclic Synthesis: Novel Synthesis of Some Pyrazoles, Pyrimidines, Imidazo[1,2-a]Pyrimidines, Pyrazolo[1,5-a]Pyrimidines, Pyrido-(Pyrimido)Pyrazolo[1,5-a]Pyrimidines, 1,2,4-Triazolo[." Journal of the Chinese Chemical Society 54, no. 4 (2007): 1075–85. http://dx.doi.org/10.1002/jccs.200700154.

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15

CHIMICHI, S., F. BRUNI, B. COSIMELLI, S. SELLERI, and G. VALLE. "ChemInform Abstract: Chemistry of Substituted Pyrazolo(1,5-a)pyrimidines. Part 5. 7-Oxo-6-( pyrazol-3′(5′)-yl)-4,7-dihydropyrazolo(1,5-a)pyrimidines from 6- Ethoxycarbonyl-7-(2-dimethylaminovinyl)pyrazolo(1,5-a)pyrimidines: Elucidation of the Reaction Mec." ChemInform 27, no. 37 (2010): no. http://dx.doi.org/10.1002/chin.199637215.

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16

Kathrotiya, Haresh G., and Yogesh T. Naliapara. "Synthesis of Novel Highly Substituted Pyrimidines Bearing Furanyl Thiazole Nucleous." International Letters of Chemistry, Physics and Astronomy 60 (September 2015): 47–57. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.60.47.

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A series of novel highly substituted pyrimidines bearing furanyl thiazole nucleous have been synthesized. In which reaction of guanidine nitrate with ketene dithioacetals 3c produced substituted pyrimidines 4d which further treated with various aromatic aldehydes to afford title compounds 5(a-t). The chemical structures of the synthesized compounds were elucidated by 1H NMR, 13C NMR, FT-IR, elemental analysis, and mass spectral data.

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17

Edmont, Dolorès, and David M. Williams. "A new and versatile synthesis of 5-substituted pyrrolo[2,3-d]pyrimidines." Tetrahedron Letters 41, no. 44 (2000): 8581–85. http://dx.doi.org/10.1016/s0040-4039(00)01491-x.

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18

Wilding, Birgit, Stefan Faschauner, and Norbert Klempier. "ChemInform Abstract: A Practical Synthesis of 5-Functionalized Thieno[2,3-d]pyrimidines." ChemInform 46, no. 44 (2015): no. http://dx.doi.org/10.1002/chin.201544190.

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19

Dodonova, Jelena, and Sigitas Tumkevicius. "Fused Pyrrolo[2,3-d]pyrimidines (7-Deazapurines) by Palladium-Catalyzed Direct N–H and C–H Arylation Reactions." Synthesis 49, no. 11 (2017): 2523–34. http://dx.doi.org/10.1055/s-0036-1588734.

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Palladium-catalyzed intramolecular direct C–H arylations for the synthesis of hitherto unknown fused hetero systems containing an incorporated pyrrolo[2,3-d]pyrimidine scaffold are described. Pyrimido[5′,4′:4,5]pyrrolo[2,1-a]isoindoles were synthesized from 2,4-diarylpyrrolo[2,3-d]pyrimidines and o-bromobenzyl bromides by using a cascade N-benzylation/C–H arylation reaction sequence. A series of pyrimido[5′,4′:4,5]pyrrolo[1,2-f]phenanthridines were successfully assembled via a domino process involving the palladium-catalyzed direct double C–H arylation reactions of 2,4,7-triarylpyrrolo[2,3-d]

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20

Abarbri, Mohamed, Badr Jismy, Hassan Allouchi, Gérald Guillaumet, and Mohamed Akssira. "An Efficient Synthesis of New 7-Trifluoromethyl-2,5-disubstituted Pyrazolo[1,5-a]pyrimidines." Synthesis 50, no. 08 (2018): 1675–86. http://dx.doi.org/10.1055/s-0036-1591752.

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A novel two-step synthesis of trifluoromethylated 3,5-disubstituted pyrazolo[1,5-a]pyrimidines is reported from 3-aminopyrazoles and ethyl 4,4,4-trifluorobut-2-ynoate. The synthetic route begins with the one-pot synthesis of 7-trifluoromethylated pyrazolo[1,5-a]pyrimidin-5-ones by condensation of 3-aminopyrazoles with a fluorinated alkyne. The products obtained are used as building blocks to synthesize directly, with excellent yields via C–O bond activation, a library of new fluorinated 3,5-disubstituted pyrazolo[1,5-a]pyrimidines of biological interest. This operation efficiently allows C–C,

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21

Borrell, José I., Jordi Teixidó, Blanca Martínez-Teipel, et al. "An Unequivocal Synthesis of 4-Amino-1,5,6,8-tetrahydropyrido[2,3-d]pyrimidine-2,7-diones and 2-Amino-3,5,6,8-tetrahydropyrido[2,3-d]pyrimidine-4,7-diones." Collection of Czechoslovak Chemical Communications 61, no. 6 (1996): 901–9. http://dx.doi.org/10.1135/cccc19960901.

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An unequivocal set of procedures for the synthesis of 4-amino-1,5,6,8-tetrahydropyrido[2,3-d]pyrimidine-2,7-diones (7) and 2-amino-3,5,6,8-tetrahydropyrido[2,3-d]pyrimidine-4,7-diones (8), in a maximum of four steps from an α,β-unsaturated ester 1, is reported. Thus, the acid hydrolysis of the 2,4-diaminopyrido[2,3-d]pyrimidines 3 yields the 4-amino-2-oxopyrido[2,3-d]pyrimidines 7 while the cyclization of the Michael adducts 9 (formed by reaction of 1 and methyl cyanoacetate) with guanidine affords the corresponding 2-amino-4-oxopyrido[2,3-d]pyrimidines 8. Both isomers were also obtained by hy

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22

Gabriel, Frédéric, Ayman Sabra, Sofiane El-Kirat-Chatel, et al. "Deletion of the Uracil Permease Gene Confers Cross-Resistance to 5-Fluorouracil and Azoles in Candida lusitaniae and Highlights Antagonistic Interaction between Fluorinated Nucleotides and Fluconazole." Antimicrobial Agents and Chemotherapy 58, no. 8 (2014): 4476–85. http://dx.doi.org/10.1128/aac.00009-14.

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ABSTRACTWe characterized two additional membrane transporters (Fur4p and Dal4p) of the nucleobase cation symporter 1 (NCS1) family involved in the uptake transport of pyrimidines and related molecules in the opportunistic pathogenic yeastCandida lusitaniae. Simple and multiple null mutants were constructed by gene deletion and genetic crosses. The function of each transporter was characterized by supplementation experiments, and the kinetic parameters of the uptake transport of uracil were measured using radiolabeled substrate. Fur4p specifically transports uracil and 5-fluorouracil. Dal4p is

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23

Bronk, J. R., Norma Lister, and Susan Lynch. "Absorption of 5-fluorouracil and related pyrimidines in rat small intestine." Clinical Science 72, no. 6 (1987): 705–16. http://dx.doi.org/10.1042/cs0720705.

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1. The transport of 5-fluorouracil, uracil and thymine has been studied with isolated jejunal loops of rat small intestine. High performance liquid chromatography was used to identify the pyrimidines and measure their concentrations. 2. When the lumen of the intestine was perfused with 5-fluorouracil or uracil at 0.1 mmol/l or 0.2 mmol/l, the concentration in the serosal secretions was significantly higher than that in the lumen. For thymine the serosal concentration exceeded that in the lumen only at 0.1 mmol/l. 3. Analysis of the mucosal tissue water at the end of the perfusion demonstrated

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24

Gad-Elkareem, Mohamed A. M., Azza M. Abdel-Fattah, and Mohamed A. A. Elneairy. "Pyrazolo[3,4-b]pyridine in heterocyclic synthesis: synthesis of new pyrazolo[3,4-b]pyridines, imidazo[1',2':1,5]pyrazolo[3,4-b]pyridines, and pyrido[2',3':3,4]pyrazolo[1,5-a]pyrimidines." Canadian Journal of Chemistry 85, no. 9 (2007): 592–99. http://dx.doi.org/10.1139/v07-089.

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Pyrazolo[3,4-b]pyridine derivatives 7 and 9 were synthesized via the reaction of 3-amino-1H-pyrazolo-[3,4-b]pyridine derivative 2 with ω-bromoacetophenones. Reaction of 7 and 9 with Ac2O afforded the imidazo[1',2':1,5]py razolo[3,4-b]pyridine derivative 8 and pyrazolo[3,4-b]pyridine derivative 10, respectively. Reaction of 2 with chloroacetonitrile followed by DMF-DMA gave imidazo[1',2':1,5]pyrazolo[3,4-b]pyridines 4 and 5, respectively. Acetyl acetone and 1,1-dicyano-2,2-dimethylthioethene were reacted with 2 to afford the pyrido[2',3':3,4]pyrazolo-[1,5-a]-pyrimidines 11 and 14, respectively.

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25

Bondock, Samir, Abd El-Gaber Tarhoni, and Ahmed A. Fadda. "Regioselective Synthesis of Some New Pyrazolo[1,5-a]pyrimidines, Pyrazolo[1,5-a]quinazoline and Pyrimido[4′,5′:3,4]pyrazolo[1,5-a] pyrimidines Containing Thiazole Moiety." Journal of Heterocyclic Chemistry 52, no. 6 (2014): 1792–99. http://dx.doi.org/10.1002/jhet.2278.

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26

Lu, Qiuyu, Wei He, Wen Sun, Ye Feng, Li Zhan, and Yu Luo. "Synthesis of 2-arylamino-5-formyl-pyrimidines from the bis(hexafluorophosphate) Arnold salt." Journal of Chemical Research 44, no. 9-10 (2020): 580–85. http://dx.doi.org/10.1177/1747519820911271.

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A three-step synthesis of 2-arylamino-5-formyl-pyrimidines is developed by condensation of the bis(hexafluorophosphate) Arnold salt with N-arylguanidines. This method conveniently provides the corresponding 2-arylaminopyrimidine derivatives in good yields.

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27

Dobado, Jose A., Sonja Grigoleit, and José Molina Molina. "Theoretical characterization of 5-oxo, 7-oxo and 5-oxo-7-amino[1,2,4]triazolo[1,5-a]pyrimidines †." Journal of the Chemical Society, Perkin Transactions 2, no. 8 (2000): 1675–80. http://dx.doi.org/10.1039/b002527p.

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28

Reynolds, Robert C., Todd W. Trask, and W. David Sedwick. "2,4-Dichloro-5-(1-o-carboranylmethyl)-6-methylpyrimidine: a potential synthon for 5-(1-o-carboranylmethyl)pyrimidines." Journal of Organic Chemistry 56, no. 7 (1991): 2391–95. http://dx.doi.org/10.1021/jo00007a026.

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29

Chevrier, F., Z. Chamas, T. Lequeux, et al. "Synthesis of 5,5-difluoro-5-phosphono-pent-2-en-1-yl nucleosides as potential antiviral agents." RSC Advances 7, no. 51 (2017): 32282–87. http://dx.doi.org/10.1039/c7ra05153k.

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A series of hitherto unknown acyclic 5,5-difluoro-5-phosphono-pent-2-en-1-yl-pyrimidines, -purines and -(1,2,4)-triazolo-3-carboxamide were successfully synthesized from (E)-1-bromo-5-diethoxyphosphoryl-5,5-difluoro-pent-2-ene in a stereoselective manner.

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30

Zanatta, Nilo, Laura Souza, Josiane Santos та ін. "Synthetic Versatility of β-Alkoxyvinyl Trichloromethyl Ketones for Obtaining [1,2,4]Triazolo[1,5-a]pyrimidines". Synthesis 50, № 18 (2018): 3686–95. http://dx.doi.org/10.1055/s-0037-1610191.

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The synthetic versatility of 4-alkoxy-4-alkyl/aryl-1,1,1-trichloroalk-3-en-2-ones (enones) for the synthesis of [1,2,4]triazolo[1,5-a]pyrimidines, in which the trichloromethyl group is either maintained or eliminated from the product by simply controlling the reaction medium, is reported. These enones react with 3-amino-1H-1,2,4-triazoles under acidic conditions to furnish exclusively 7-(trichloromethyl)-[1,2,4]triazolo[1,5-a]pyrimidines, whereas under basic conditions [1,2,4]triazolo[1,5-a]pyrimidin-5/7(1H)-ones are obtained with elimination of the trichloromethyl group. The regioselectivity

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31

Umamahesh, Balijapalli, Triveni Rajashekhar Mandlimath, and Kulathu I. Sathiyanarayanan. "Correction: A novel, facile, rapid, solvent free protocol for the one pot green synthesis of chromeno[2,3-d]pyrimidines using reusable nano ZnAl2O4 – a NOSE approach and photophysical studies." RSC Advances 5, no. 67 (2015): 54124. http://dx.doi.org/10.1039/c5ra90061a.

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Correction for 'A novel, facile, rapid, solvent free protocol for the one pot green synthesis of chromeno[2,3-d]pyrimidines using reusable nano ZnAl<sub>2</sub>O<sub>4</sub> – a NOSE approach and photophysical studies' by Balijapalli Umamahesh et al., RSC Adv., 2015, 5, 6578–6587.

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32

Mcfadden, HG, and JL Huppatz. "Synthesis of 4,6-Dialkylpyrimidine-5-carbonitriles." Australian Journal of Chemistry 45, no. 6 (1992): 1045. http://dx.doi.org/10.1071/ch9921045.

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4,6-Dialkylpyrimidine-5-carbonitriles were synthesized from 2-(1-ethoxyalkylidine)-3-oxoalkane-nitriles and bidentate nucleophiles such as thiourea in the presence of sodium ethoxide. The synthesis was found to be limited to dialkylpyrimidines where both alkyl groups contained between one and three carbons. Subsequent derivatization of the 2-thioxo function provides scope for the synthesis of a variety of novel pyrimidines.

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33

Sakhno, Yana I., Maryna V. Murlykina, Oleksandr I. Zbruyev, et al. "Ultrasonic-assisted unusual four-component synthesis of 7-azolylamino-4,5,6,7-tetrahydroazolo[1,5-a]pyrimidines." Beilstein Journal of Organic Chemistry 16 (February 27, 2020): 281–89. http://dx.doi.org/10.3762/bjoc.16.27.

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Four-component reactions of 3-amino-1,2,4-triazole or 5-amino-1H-pyrazole-4-carbonitrile with aromatic aldehydes and pyruvic acid or its esters under ultrasonication were studied. Unusual for such a reaction type, a cascade of elementary stages led to the formation of 7-azolylaminotetrahydroazolo[1,5-a]pyrimidines.

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34

Edmont, Dolores, and David M. Williams. "ChemInform Abstract: A New and Versatile Synthesis of 5-Substituted Pyrrolo[2,3-d]pyrimidines." ChemInform 32, no. 4 (2001): no. http://dx.doi.org/10.1002/chin.200104172.

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35

Bondock, Samir, Abd El-Gaber Tarhoni, and Ahmed A. Fadda. "ChemInform Abstract: Regioselective Synthesis of Some New Pyrazolo[1,5-a]pyrimidines, Pyrazolo[1,5-a]quinazoline and Pyrimido[4′,5′:3,4]pyrazolo[1,5-a] Pyrimidines Containing Thiazole Moiety." ChemInform 47, no. 10 (2016): no. http://dx.doi.org/10.1002/chin.201610192.

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36

Párkányi, Cyril, Hui Liang Yuan, Martha C. Marín-Montes, and Hans T. Essoussi. "Synthesis of polymethylene chain-bridged 6-substituted 8-azapurines and related compounds." Collection of Czechoslovak Chemical Communications 56, no. 11 (1991): 2382–88. http://dx.doi.org/10.1135/cccc19912382.

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The synthesis of a series of polymethylene chain-bridged 8-azapurines as potential DNA intercalating agents is described. N,N’-Bis(5-amino-6-chloro-4-pyrimidyl)-1,3-diaminopropane (III), N,N”-bis(5-amino-6chloro-4-pyrimidyl)-1,8-diaminooctane (IV), and N,N’-bis(5-amino-6-chloro-4-pyrimidyl)-1,12-diaminododecane (V) were synthesized from 5-amino-4,6-dichloropyrimidine (I) and 1,3-diaminopropane (II, n = 3), 1,8-diaminooctane (II, n = 8), and 1,12-diaminododecane (II, n = 12), respectively, as the starting materials. 1,3-Bis(6-chloro-9-purinyl)propane (VI), 1,8-bis(6-chloro-9-purinyl)octane (VII

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37

Tkachenko, Irina G., Sergey A. Komykhov, Vladimir I. Musatov, et al. "In water multicomponent synthesis of low-molecular-mass 4,7-dihydrotetrazolo[1,5-a]pyrimidines." Beilstein Journal of Organic Chemistry 15 (October 8, 2019): 2390–97. http://dx.doi.org/10.3762/bjoc.15.231.

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The three-component reaction of 5-aminotetrazole with aliphatic aldehydes (formaldehyde, acetaldehyde) and acetoacetic ester derivatives in water under microwave irradiation leads to the selective formation of 4,7-dihydrotetrazolo[1,5-a]pyrimidine derivatives. Under similar conditions using 4,4,4-trifluoroacetoacetic ester 5-hydroxy-4,5,6,7-tetrahydrotetrazolo[1,5-a]pyrimidines are obtained. The analogous reaction with acetylacetone requires scandium(III) triflate as catalyst. The antioxidant activity of selected compounds was assayed with 1,1-diphenyl-2-picrylhydrazyl.

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38

Chimichi, Stefano, Fabrizio Bruni, Barbara Cosimelli, Silvia Selleri, and Giovanni Valle. "Chemistry of substituted pyrazolo[1,5-a]pyrimidines. Part 5. 7-Oxo-6-[pyrazol-3′(5′)-yl]-4,7-dihydropyrazolo[1,5-a]pyrimidines from 6-ethoxycarbonyl-7-(2-dimethylaminovinyl)pyrazolo[1,5-a]-pyrimidines: elucidation of the reaction mechanism through NMR spectroscopy and X-ray diffraction analysis." J. Chem. Soc., Perkin Trans. 2, no. 6 (1996): 1147–52. http://dx.doi.org/10.1039/p29960001147.

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Brown, DJ, BJ Cronin, S. Lan, and G. Nardo. "Heterocyclic Amplifiers of Phleomycin. VII. Phenyl-, Tolyl-, Phenoxy- and Benzyl-pyrimidines; also Some Carbocyclic Analogues." Australian Journal of Chemistry 38, no. 5 (1985): 825. http://dx.doi.org/10.1071/ch9850825.

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Synthetic routes are described for 5-phenyl-, 5-p-chlorophenyl-, 2-p-tolyl-, 2- and 4-benzyl- and 4-phenoxy-pyrimidines, each bearing a sulfur-, nitrogen- or oxygen-linked basic side chain; also to analogous biphenyls and a diphenylmethane . These compounds were required for evaluation as amplifiers of phleomycin.

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40

Abdelhamid, Abdou O., Abdelgawad A. Fahmi, and Basma S. Baaiu. "A Convenient Synthesis of Some New 1,3,4-Thiadiazoles, Thiazoles, Pyrazolo[1,5-a]pyrimidines, Pyrazolo[5,1-c]triazine, and Thieno[3,2-d]pyrimidines Containing 5-Bromobenzofuran Moiety." Journal of Heterocyclic Chemistry 53, no. 4 (2015): 1292–303. http://dx.doi.org/10.1002/jhet.2383.

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41

Yang, Ru Chun, Hui Zhu, Xuan Ye Jin, Qiang Xiao, and Yong Ju. "Synthesis of Bicyclic Furo[2,3-d]pyrimidine Deoxynucleosides Conjugated with N-Diisopropylphosphoryl Amino Acids." Advanced Materials Research 881-883 (January 2014): 405–9. http://dx.doi.org/10.4028/www.scientific.net/amr.881-883.405.

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A series of bicyclic furo[2,3-d]pyrimidine nucleosides conjugated with N-diisopropylphosphoryl amino acids were synthesized from 2′-deoxy-5-iodouridine. The key step is its cross coupling with the 5-phthalimido-1-pentyne under Sonogashira reaction condition. 5-Endo-dig electrophilic cyclization catalyzed by AgNO3 is used to afford the furo[2,3-d]pyrimidines.

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Solomyannyi, Roman, Sergii Slivchuk, Donald Smee, et al. "In vitro Activity of the Novel Pyrimidines and Their Condensed Derivatives Against Poliovirus." Current Bioactive Compounds 15, no. 5 (2019): 582–91. http://dx.doi.org/10.2174/1573407214666180720120509.

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Background: Substituted pyrimidine derivatives (non-nucleoside) are found to be associated with various biological activities. The various substituted pyrimidines are also having significant in vitro activity against different DNA and RNA viruses. The present study focuses on the anti-PV activity of new pyrimidines and their condensed derivatives. Methods: A series of novel pyrimidines and their condensed derivatives were synthesized and their structures were confirmed by spectral data. Their antiviral activities against poliovirus type 3 (PV-3) were evaluated in vitro. In cell culture, morpho

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43

Suresh, Lingala, P. Sagar Vijay Kumar, T. Vinodkumar, and G. V. P. Chandramouli. "Heterogeneous recyclable nano-CeO2 catalyst: efficient and eco-friendly synthesis of novel fused triazolo and tetrazolo pyrimidine derivatives in aqueous medium." RSC Advances 6, no. 73 (2016): 68788–97. http://dx.doi.org/10.1039/c6ra16307f.

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A ceria nanocatalyst was used for the one-pot, multicomponent condensation reaction of benzoylacetonitrile, aromatic aldehydes and 5-amino-triazole/tetrazole proceeding via C–C and C–N bond formation to deliver triazolo/tetrazolo[1,5-a]pyrimidines.

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Kaishap, Partha Pratim, Swagata Baruah, Kommuri Shekarrao, Sanjib Gogoi, and Romesh C. Boruah. "A facile method for the synthesis of steroidal and nonsteroidal 5-methyl pyrazolo[1,5-a]pyrimidines." Tetrahedron Letters 55, no. 19 (2014): 3117–21. http://dx.doi.org/10.1016/j.tetlet.2014.04.011.

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Fatima, Seerat, Anindra Sharma, Rahul Sharma, and Rama P. Tripathi. "A Simple and Efficient One-Pot Synthesis of Multifunctional 5-Aryl-5H-thiazolo[3,2-a]pyrimidines." Journal of Heterocyclic Chemistry 49, no. 3 (2012): 600–606. http://dx.doi.org/10.1002/jhet.831.

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REYNOLDS, R. C., T. W. TRASK, and W. D. SEDWICK. "ChemInform Abstract: 2,4-Dichloro-5-(1-o-carboranylmethyl)-6-methylpyrimidine: A Potential Synthon for 5-(1-o-Carboranylmethyl)pyrimidines." ChemInform 22, no. 34 (2010): no. http://dx.doi.org/10.1002/chin.199134193.

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47

Nicolle, Edwige, Martine Benoit-Guyod, Claude Gey, and Gérard Leclerc. "Regioisomers Differentiation of 5- (and 7)-Oxo-tetrahydro-7 (and 5)H-thiazolo[3,2-a]pyrimidines. NMR Spectroscopic Studies." Spectroscopy Letters 26, no. 7 (1993): 1155–70. http://dx.doi.org/10.1080/00387019308011600.

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48

Abdel-fattah, A. M., As Aly, F. A. Gad, M. E. A. Zaki, and A. B. A. El-gazzar. "A FACILE SYNTHESIS OF ISOXAZOLO [5′,4′:4,5]THIAZOLO[3,2-a]THIENO PYRIMIDINES A NEW RING SYSTEM." Phosphorus, Sulfur, and Silicon and the Related Elements 141, no. 1 (1998): 263–81. http://dx.doi.org/10.1080/10426509808033738.

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49

Zeng, Qing, Demin Ren, Aiting Zheng, and Xiaofang Li. "Synthesis of Octahydropyrano[2,3-d]Pyrimidine Derivatives via Tetrahydropyrano[3,2-e][1,3]Thiazolo[3,2-a]Pyrimidine and 2,6-Dichlorobenzonitrile Oxide." Journal of Chemical Research 42, no. 6 (2018): 317–19. http://dx.doi.org/10.3184/174751918x15293130141511.

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N1-substituted octahydro-1 H-pyrano[2,3- d]pyrimidines derivatives were prepared in moderate yield by the reaction of methyl [(4a RS,5 SR,10a RS)-5-aryl-2-oxo-3,4,4 a,10 a-tetrahydro-2 H,5 H-pyrano[3,2- e][1,3]thiazolo[3,2- a]pyrimidin-8(9 H)-ylidene]acetate and 2,6-dichorobenzonitrile oxide via a domino 1,3-dipolar cycloaddition/ring-opening/dethionation process. The structures of the products were characterised by spectroscopic and X-ray crystallographic analysis.

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50

Abdelhamid, Abdou O., Victorin B. Baghos, and Mervat M. A. Halim. "Synthesis and reactivity of N-[3-amino-4-(benzoxazol-2-yl)pyrazol-5-yl]phenylamine." Journal of Chemical Research 2007, no. 7 (2007): 420–25. http://dx.doi.org/10.3184/030823407x228830.

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Pyrazolo[5,1- a]pyrimidines and pyrazolo[5,1-c][1,2,4]triazines containing benzooxazole moiety are synthesised from N-[3-amino-4-(benzoxazol-2-yl)pyrazol-5-yl]phenylamine or its diazonium chloride with the appropriate active methylene compounds. The newly synthesised compounds were elucidated by elemental analysis, spectral data and alternative synthetic route whenever possible.

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