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Journal articles on the topic 'Xanthines'

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Published: 4 June 2021

Last updated: 7 September 2023

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1

Inamoto, Kiyofumi, Maki Shimizu, Noboru Hayama, and Tetsutaro Kimachi. "Copper-Catalyzed Intramolecular C–H Amination: A New Entry to Substituted Xanthine Derivatives." Synthesis 49, no. 18 (May 9, 2017): 4183–90. http://dx.doi.org/10.1055/s-0036-1588821.

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Catalytic synthesis of xanthines was achieved in the presence of a copper catalyst. The process involves copper-catalyzed intramolecular C–H amination of benzamidines that possess a uracil moiety and produces variously substituted xanthines generally in good to high yields. This work introduces a new, facile approach to polysubstituted xanthine compounds.

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2

Woziwodzka, Anna, Marta Krychowiak-Maśnicka, Grzegorz Gołuński, Anna Felberg, Agnieszka Borowik, Dariusz Wyrzykowski, and Jacek Piosik. "Modulatory Effects of Caffeine and Pentoxifylline on Aromatic Antibiotics: A Role for Hetero-Complex Formation." Molecules 26, no. 12 (June 14, 2021): 3628. http://dx.doi.org/10.3390/molecules26123628.

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Antimicrobial resistance is a major healthcare threat globally. Xanthines, including caffeine and pentoxifylline, are attractive candidates for drug repurposing, given their well-established safety and pharmacological profiles. This study aimed to analyze potential interactions between xanthines and aromatic antibiotics (i.e., tetracycline and ciprofloxacin), and their impact on antibiotic antibacterial activity. UV-vis spectroscopy, statistical-thermodynamical modeling, and isothermal titration calorimetry were used to quantitatively evaluate xanthine-antibiotic interactions. The antibacterial profiles of xanthines, and xanthine-antibiotic mixtures, towards important human pathogens Staphylococcus aureus, Enterococcus faecium, Escherichia coli, Acinetobacter baumannii, Klebsiella pneumoniae, and Enterobacter cloacae were examined. Caffeine and pentoxifylline directly interact with ciprofloxacin and tetracycline, with neighborhood association constant values of 15.8–45.6 M−1 and enthalpy change values up to −4 kJ·M−1. Caffeine, used in mixtures with tested antibiotics, enhanced their antibacterial activity in most pathogens tested. However, antagonistic effects of caffeine were also observed, but only with ciprofloxacin toward Gram-positive pathogens. Xanthines interact with aromatic antibiotics at the molecular and in vitro antibacterial activity level. Given considerable exposure to caffeine and pentoxifylline, these interactions might be relevant for the effectiveness of antibacterial pharmacotherapy, and may help to identify optimal treatment regimens in the era of multidrug resistance.

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3

&NA;. "Xanthines see Ephedrine/xanthines." Reactions Weekly &NA;, no. 337 (February 1991): 8. http://dx.doi.org/10.2165/00128415-199103370-00055.

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4

&NA;. "Xanthines." Reactions Weekly &NA;, no. 307 (June 1990): 8. http://dx.doi.org/10.2165/00128415-199003070-00041.

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5

Gibson, Christopher M., and Patrick W. Fowler. "Aromaticity of caffeine, xanthine and the dimethyl xanthines." Tetrahedron Letters 55, no. 13 (March 2014): 2078–81. http://dx.doi.org/10.1016/j.tetlet.2014.02.027.

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6

Aleksandrova, K. V., Ye S. Pruhlo, Ye K. Mykhalchenko, O. S. Shkoda, and O. Yu Cherchesova. "Search for potential hypoglycemic agents among potassium salts of 3-benzyl-8-substituted xanthines." Current issues in pharmacy and medicine: science and practice 15, no. 3 (November 15, 2022): 266–70. http://dx.doi.org/10.14739/2409-2932.2022.3.253385.

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Nowadays, the prevalence of metabolic syndrome (MS) is a serious problem among the world’s population. Metabolic syndrome includes the so-called “deadly” quartet – hypertension, type 2 diabetes mellitus (diabetes mellitus), dyslipidemia and alimentary obesity. After all, type 2 diabetes is included in the list of pathologies of the metabolic syndrome, it is important to find ways to alleviate the disease. Derivatives of such a heterocyclic system as xanthine are of great interest in this aspect. The aim of the study was to explore the hypoglycemic activity of newly synthesized water-soluble derivatives of 3-benzyl-8-substituted xanthines. Materials and methods. We obtained water-soluble potassium 3-benzyl-8-R-xanthin-7-ides, the structure and individuality of which were confirmed by a set of physical-chemical studies. Results. The hypoglycemic effect of the newly synthesized compounds was assessed by an oral glucose tolerance test. The obtained data were processed using modern statistical in silico-methods. Conclusions. The results of the hypoglycemic activity study among the potassium salts of 3-benzyl-8-substituted xanthine derivatives showed, that some new compounds are in close vicinity to the reference drug’s hypoglycemic action.

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7

Sánchez-Eleuterio, Alma, Carlos Mendoza-Merlos, Ricardo Corona Sánchez, Alejandra M. Navarrete-López, Anatolio Martínez Jiménez, Elsie Ramírez-Domínguez, Leticia Lomas Romero, Ricardo Orozco Cruz, Araceli Espinoza Vázquez, and Guillermo E. Negrón-Silva. "Experimental and Theoretical Studies on Acid Corrosion Inhibition of API 5L X70 Steel with Novel 1-N-α-d-Glucopyranosyl-1H-1,2,3-Triazole Xanthines." Molecules 28, no. 1 (January 3, 2023): 460. http://dx.doi.org/10.3390/molecules28010460.

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A series of novel 1-N-α-d-glucopyranosyl-1H-1,2,3-triazole xanthines was synthesized from azido sugars (glucose, galactose, and lactose) and propargyl xanthines (theophylline and theobromine) using a typical copper (I)-catalyzed azide–alkyne 1,3-dipolar cycloaddition. The corrosion inhibition activities of these new carbohydrate-xanthine compounds were evaluated by studying the corrosion of API 5 L X70 steel in a 1 M HCl medium. The results showed that, at 10 ppm, a 90% inhibition efficiency was reached by electrochemical impedance spectroscopy. The inhibitory efficiency of these molecules is explained by means of quantum chemical calculations of the protonated species with the solvent effect, which seems to better represent the actual situation of the experimental conditions. Some quantum chemical parameters were analyzed to characterize the inhibition performance of the tested molecules.

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8

&NA;. "Theophylline/xanthines." Reactions Weekly &NA;, no. 403 (May 1992): 8. http://dx.doi.org/10.2165/00128415-199204030-00031.

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9

&NA;. "Ephedrine/xanthines." Reactions Weekly &NA;, no. 337 (February 1991): 5. http://dx.doi.org/10.2165/00128415-199103370-00027.

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10

Cazzola, Mario, Luigino Calzetta, Peter J. Barnes, Gerard J. Criner, Fernando J. Martinez, Alberto Papi, and Maria Gabriella Matera. "Efficacy and safety profile of xanthines in COPD: a network meta-analysis." European Respiratory Review 27, no. 148 (May 2, 2018): 180010. http://dx.doi.org/10.1183/16000617.0010-2018.

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Theophylline can still have a role in the management of stable chronic obstructive pulmonary disease (COPD), but its use remains controversial, mainly due to its narrow therapeutic window. Doxofylline, another xanthine, is an effective bronchodilator and displays a better safety profile than theophylline. Therefore, we performed a quantitative synthesis to compare the efficacy and safety profile of different xanthines in COPD.The primary end-point of this meta-analysis was the impact of xanthines on lung function. In addition, we assessed the risk of adverse events by normalising data on safety as a function of person-weeks. Data obtained from 998 COPD patients were selected from 14 studies and meta-analysed using a network approach.The combined surface under the cumulative ranking curve (SUCRA) analysis of efficacy (change from baseline in forced expiratory volume in 1 s) and safety (risk of adverse events) showed that doxofylline was superior to aminophylline (comparable efficacy and significantly better safety), bamiphylline (significantly better efficacy and comparable safety), and theophylline (comparable efficacy and significantly better safety).Considering the overall efficacy/safety profile of the investigated agents, the results of this quantitative synthesis suggest that doxofylline seems to be the best xanthine for the treatment of COPD.

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11

Bridson, Peter K., and Xiaodong Wang. "1-Substituent Xanthines." Synthesis 1995, no. 07 (July 1995): 855–58. http://dx.doi.org/10.1055/s-1995-4017.

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12

Rodgers, Gary R., and William J. P. Neish. "Linear expanded xanthines." Monatshefte f�r Chemie Chemical Monthly 117, no. 6-7 (1986): 879–82. http://dx.doi.org/10.1007/bf00810080.

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13

&NA;. "Xanthines see Dipyridamole interaction." Reactions Weekly &NA;, no. 307 (June 1990): 8. http://dx.doi.org/10.2165/00128415-199003070-00042.

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14

Mourya, Shruti, Ramesh Bodla, Ravikant Taurean, and Akanksha Sharma. "Simultaneous estimation of xanthine alkaloids (Theophylline, Theobromine and Caffeine) by High-Performance Liquid Chromatography." International Journal of Drug Regulatory Affairs 7, no. 2 (June 16, 2019): 35–41. http://dx.doi.org/10.22270/ijdra.v7i2.315.

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Methylxanthines are mainly a group of phytochemicals which are derived from purine base xanthine. These xanthines are obtained from plant as a result of secondary metabolism. There are various physiological actions that have been attributed to these derivatives in neurogenerative diseases, respiratory diseases, cancer and diabetes. The aim of this study is to develop a suitable qualitative and quantitative method for these xanthine derivatives. HPLC method is suitable for simultaneous estimation of methylxanthines, based on their physicochemical properties. Theobromine, Theophylline and Caffeine that belongs to alkaloids possess their economic effects. They have various stimulant effects on cardiovascular system, gastrointestinal system, respiratory system, central nervous system etc. that results in increased motivation to work, increased energy and increased alertness. High performance liquid chromatography is used for simultaneous determination of theophylline, theobromine and caffeine from different tea leaves.

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15

Rockitt, Sven, Rudolf Wartchow, Helmut Duddeck, Anna Drabczynska, and Katarzyna Kiec-Kononowicz. "Modes of Xanthine Complexation to Dirhodium Tetrakis[(R)-α-methoxy-α- (trifluoromethyl)-phenylacetate] in Solution and in the Solid State." Zeitschrift für Naturforschung B 56, no. 3 (March 1, 2001): 319–24. http://dx.doi.org/10.1515/znb-2001-0317.

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Abstract It is show n by IR and NMR studies that the xanthines 1-5 prefer a side-on com plexation to the chiral dirhodium tetrakis[(R)-α-methoxy-α-(trifluoromethyl)phenylacetatel (Rh*) in solution whereas carbonyl groups are involved in the solid state. For 6, at least the carbonyl group C-6 contributes to complexation in solution as well. A lternating strands of 6 and Rh* exist in the solid state as revealed by X-ray diffraction analysis described in detail. The determination of enantiomeric excess of the chiral xanthine 6 can easily be accomplished by the “dirhodium method ” (1H and 13C NMR in the presence of Rh*).

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16

Barlinski, J., A. Lockhart, and N. Frossard. "Modulation by theophylline and enprofylline of the excitatory non-cholinergic transmission in guinea-pig bronchi." European Respiratory Journal 5, no. 10 (November 1, 1992): 1201–5. http://dx.doi.org/10.1183/09031936.93.05101201.

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The mechanism of action of xanthines in asthma remains controversial. Since sensory innervation may play a role in the pathogenesis of asthma, we investigated whether xanthines were capable of reducing the contractile response of the bronchi to nerve stimulation. In guinea-pig bronchi in vitro, electrical field stimulation (EFS: 40 V, 16 Hz, 0.2 ms during 10 s) induces a rapid cholinergic contraction followed by a long-lasting contraction due to a local release of neuropeptides from C-fibre endings. We measured isometric neuronally-mediated contractions of bronchial smooth muscle and studied the effects of increasing concentrations of two xanthine derivatives, theophylline, an antagonist of adenosine receptors, and enprofylline, which has no effect on adenosine receptors. Both enprofylline (1-50 microM) and theophylline (10-100 microM) inhibited, in a concentration-dependent manner, the peptidergic contraction, an effect which was more marked with enprofylline than theophylline (EC50 = 9.6 +/- 0.7 microM and 62.0 +/- 4.7 microM, respectively). Conversely, the cholinergic response was unaffected. Contractions induced by exogenous substance P (0.03-3 microM) were also unaffected by theophylline and enprofylline at the above mentioned EC50s. Our results suggest that concentrations of theophylline, similar to those used therapeutically, reduce the release of sensory neuropeptides from C-fibre endings. This effect is unrelated to adenosine receptor blockade, since enprofylline had a similar inhibitory effect.

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17

Levi-Schaffer, Francesca, and Elka Touitou. "Xanthines Inhibit 3T3 Fibroblast Proliferation." Skin Pharmacology and Physiology 4, no. 4 (1991): 286–90. http://dx.doi.org/10.1159/000210963.

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18

BRIDSON, P. K., and X. WANG. "ChemInform Abstract: 1-Substituted Xanthines." ChemInform 26, no. 49 (August 17, 2010): no. http://dx.doi.org/10.1002/chin.199549196.

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19

Cable, Karl M. "Syntheses of isotopically labelled xanthines." Journal of Labelled Compounds and Radiopharmaceuticals 50, no. 5-6 (2007): 509–10. http://dx.doi.org/10.1002/jlcr.1229.

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20

Persson, Carl G. A., and Birgitta Gustafsson. "Tracheal relaxation from combinations of xanthines and of aβ 2-receptor agonist and xanthines." Lung 164, no. 1 (December 1986): 33–40. http://dx.doi.org/10.1007/bf02713627.

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21

Nagel, Wolfram, and Uri Katz. "Xanthine derivatives without PDE effect stimulate voltage-activated chloride conductance of toad skin." American Journal of Physiology-Cell Physiology 284, no. 2 (February 1, 2003): C521—C527. http://dx.doi.org/10.1152/ajpcell.00276a.2002.

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The effect of xanthine derivatives on the voltage-activated Cl− conductance ( G Cl) of amphibian skin was analyzed. 3-Isobutyl-1-methylxanthine (IBMX) and the recently synthesized xanthine derivatives 3,7-dimethyl-1-propyl xanthine (X-32) and 3,7-dimethyl-1-isobutyl xanthine (X-33), which lack inhibitory effects on phosphodiesterases in CHO and Calu-3 cells, increased voltage-activated G Cl without effect on baseline conductance at inactivating voltage. Half-maximal stimulation of G Cl occurred at 108 ± 9 μM for X-32 and X-33 after apical or basolateral application. The stimulation of G Cl, which occurs only in the presence of Cl− in the mucosal solution, is caused by a shift of the voltage sensitivity to lower clamp potentials and an increase of the maximally activated level. Furosemide reversed both the shift of sensitivity and the increase in magnitude. These patterns are fundamentally different from those seen after application of membrane-permeant, nonmetabolized analogs of cAMP, and they indicate that the xanthines stimulate G Cl directly. This notion is strengthened by the lack of influence on intracellular cAMP content, which is consistent with the observations in CHO and Calu-3 cells. We propose that the xanthine derivatives increase the voltage sensitivity of a regulative component in the conductive Cl− pathway across amphibian skin.

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22

Camiruaga, Ander, Imanol Usabiaga, Viola C. D’mello, Gustavo A. García, Sanjay Wategaonkar, and José A. Fernández. "Revisiting the spectroscopy of xanthine derivatives: theobromine and theophylline." Physical Chemistry Chemical Physics 21, no. 48 (2019): 26430–37. http://dx.doi.org/10.1039/c9cp05068j.

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23

Kasabova-Angelova, Alexandra, Diana Tzankova, Javor Mitkov, Maya Georgieva, Virginia Tzankova, Alexander Zlatkov, and Magdalena Kondeva-Burdina. "Xanthine Derivatives as Agents Affecting Non-dopaminergic Neuroprotection in Parkinson’s Disease." Current Medicinal Chemistry 27, no. 12 (April 23, 2020): 2021–36. http://dx.doi.org/10.2174/0929867325666180821153316.

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Parkinson's Disease (PD) is a neurodegenerative and debilitating disease that affects 1% of the elderly population. Patient’s motor disability results in extreme difficulty to deal with daily activities. Conventional treatment is limited to dopamine replacement therapy, which fails to delay disease’s progression and is often associated with a number of adverse reactions. Recent progress in understanding the mechanisms involved in PD has revealed new molecular targets for therapeutic approaches. Among them, caffeine and xanthine derivatives are promising drug candidates, because of the possible symptomatic benefits in PD. In fact, consumption of coffee correlates with a reduced risk of PD. Over the last decades, a lot of efforts have been made to uncover the therapeutic potential of xanthine structures. The substituted xanthine molecule is used as a scaffold for the synthesis of new compounds with protective effects in neurodegenerative diseases, including PD, asthma, cancer and others. The administration of the xanthines has been proposed as a non-dopaminergic strategy for neuroprotection in PD and the mechanisms of protection have been associated with antagonism of adenosine A2A receptors and Monoamine Oxidase type B (MAO-B) inhibition. The current review summarizes frequently suspected non-dopaminergic neuroprotective mechanisms and the possible beneficial effects of the xanthine derivatives in PD, along with some synthetic approaches to produce perspective xanthine derivatives as non-dopaminergic agents in PD treatment.

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24

Changenet-Barret, Pascale, Lajos Kovács, Dimitra Markovitsi, and Thomas Gustavsson. "Xanthines Studied via Femtosecond Fluorescence Spectroscopy." Molecules 21, no. 12 (December 3, 2016): 1668. http://dx.doi.org/10.3390/molecules21121668.

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25

Vree, T. B., L. Riemens, and P. M. Koopman-Kimenai. "High-performance liquid chromatography of xanthines." Journal of Chromatography B: Biomedical Sciences and Applications 428 (January 1988): 311–19. http://dx.doi.org/10.1016/s0378-4347(00)83922-5.

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26

PERSSON, C., and A. DRACO. "Xanthines as airway anti-inflammatory drugs." Journal of Allergy and Clinical Immunology 81, no. 3 (March 1988): 615–17. http://dx.doi.org/10.1016/0091-6749(88)90203-5.

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27

Navarrete Casas, R., A. García Rodriguez, F. Rey Bueno, A. Espínola Lara, C. Valenzuela Calahorro, and A. Navarrete Guijosa. "Interactions of xanthines with activated carbon." Applied Surface Science 252, no. 17 (June 2006): 6022–25. http://dx.doi.org/10.1016/j.apsusc.2005.11.020.

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28

Navarrete Casas, R., A. García Rodríguez, F. Rey Bueno, A. Espínola Lara, C. Valenzuela Calahorro, and A. Navarrete Guijosa. "Interactions of xanthines with activated carbon." Applied Surface Science 252, no. 17 (June 2006): 6026–30. http://dx.doi.org/10.1016/j.apsusc.2005.11.021.

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29

Gulevskaya, A. V., and A. F. Pozharskii. "Synthesis of N-substituted xanthines (review)." Chemistry of Heterocyclic Compounds 27, no. 1 (January 1991): 1–23. http://dx.doi.org/10.1007/bf00633208.

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30

Troke, J. A. "Approaches to the labelling of xanthines." International Journal of Radiation Applications and Instrumentation. Part A. Applied Radiation and Isotopes 39, no. 6 (1988): 540. http://dx.doi.org/10.1016/0883-2889(88)90257-2.

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31

Sahnoun, Sophian, Samir Messaoudi, Jean-Daniel Brion, and Mouâd Alami. "Palladium-Catalyzed Direct Benzylation of Xanthines." ChemCatChem 3, no. 5 (March 17, 2011): 893–97. http://dx.doi.org/10.1002/cctc.201000439.

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32

Liubchak, Kostiantyn, Andrey Tolmachev, Oleksandr O. Grygorenko, and Kostiantyn Nazarenko. "An approach to alicyclic ring-fused xanthines." Tetrahedron 68, no. 41 (October 2012): 8564–71. http://dx.doi.org/10.1016/j.tet.2012.08.014.

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33

Valero, F., R. De la Torre, and J. Segura. "Abus des xanthines dans le sport: dyphylline." Science & Sports 7, no. 2 (October 1992): 121–22. http://dx.doi.org/10.1016/s0765-1597(05)80183-2.

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34

Miyamoto, Ken-Ichi, Ryosuke Sakai, Yasunori Yamamoto, Kayo Konno, Fujiko Sanae, Takaaki Hasegawa, and Kenzo Takagi. "Selective Bronchodilators from 1-(5′-Oxohexyl)xanthines." Journal of Pharmacy and Pharmacology 44, no. 11 (November 1992): 888–92. http://dx.doi.org/10.1111/j.2042-7158.1992.tb03230.x.

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35

He, Rongjun, Shi Min Ching, and Yulin Lam. "Traceless Solid-Phase Synthesis of Substituted Xanthines." Journal of Combinatorial Chemistry 8, no. 6 (November 2006): 923–28. http://dx.doi.org/10.1021/cc060092+.

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36

Martof, Mary T., and Dorothy K. Knox. "The Effect of Xanthines on Fluid Balance." Clinical Nursing Research 6, no. 2 (May 1997): 186–96. http://dx.doi.org/10.1177/105477389700600207.

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37

Heizmann, Gerhard, and Alex N. Eberle. "Xanthines as a scaffold for molecular diversity." Molecular Diversity 2, no. 3 (March 1997): 171–74. http://dx.doi.org/10.1007/bf01682205.

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38

GULEVSKAYA, A. V., and A. F. POZHARSKII. "ChemInform Abstract: Synthesis of N-Substituted Xanthines." ChemInform 23, no. 6 (August 22, 2010): no. http://dx.doi.org/10.1002/chin.199206315.

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39

Alvarez-Lorenzo, C., A. Castiñeiras, A. Frontera, I. García-Santos, J. M. González-Pérez, J. Niclós-Gutiérrez, I. Rodríguez-González, E. Vílchez-Rodríguez, and J. K. Zaręba. "Recurrent motifs in pharmaceutical cocrystals involving glycolic acid: X-ray characterization, Hirshfeld surface analysis and DFT calculations." CrystEngComm 22, no. 40 (2020): 6674–89. http://dx.doi.org/10.1039/d0ce01064b.

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Crystallization studies on some pyridinecarboxamides and methylated xanthines with glycolic acid as coformer, were carried out on formation of synthons and their influence on stability and solubility, the energy landscape and stabilization energies.

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40

Mincsovics, Emil, Márta Garami, László Kecskés, Barnabás Tapa, Zoltán Végh, György Kátay, and Ernó Tyihák. "Personal Overpressured-Layer Chromatography (OPLC) Basic System 50, Flexible Tool in Analytical and Semipreparative Work." Journal of AOAC INTERNATIONAL 82, no. 3 (May 1, 1999): 587–98. http://dx.doi.org/10.1093/jaoac/82.3.587.

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Abstract A new automated overpressured-layer chromatographic (OPLC) system called the Personal OPLC Basic System 50 is suitable for analytical and semi preparative separations. The automatic microprocessor-controlled system ensures rapid and reproducible off-line isocratic and stepwise gradientseparations. High external pressure (5 MPa) makes the sorbent layer more homogeneous, yielding more efficient off-line separation compared with those by early Chrompres chambers. A theoretical plate height of 10–30 μm can be achieved on an analytical high-performance thin-layer chromatographic (HPTLC) layer made of irregular silica gel with an average particle size of 5 μm if an optimal linear velocity (20–40 mm/min) and a nonviscous solvent system are used. On an analytical layer of 3 μm spherical silica gel, a theoretical plate height of 6–15 μm can be reached. Rapid analytical separations of resveratrol (1555 s) and xanthine by one-(498s) and two-directional (274 s) off-line developments were accomplished. On-line separation and detection combined with off-line sample application and fully on-line processing (including on-line sample application, separation, and detection) were fulfilled with a TLC plate for xanthine separation. Semi preparative isolation of xanthines was achieved through a fully on-line OPLC operating mode and scaled-up chromatography.

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41

Kapri, Anandi, Nitin Gupta, and Sumitra Nain. "Recent Advances in the Synthesis of Xanthines: A Short Review." Scientifica 2022 (November 8, 2022): 1–24. http://dx.doi.org/10.1155/2022/8239931.

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Xanthine and its derivatives are considered a pharmacologically potential moiety that manifests immense biological activities. Owing to this much diversity in the biological field, this scaffold has fascinated the attention of many researchers around the globe to scrutinize its basic structure chemically as well as biologically. In recent years, xanthine derivatives have been used therapeutically in different pathological conditions due to their presence in day-to-day life. Herein, we review the recent progress in the synthesis of xanthine and its derivatives. Some of the widely used synthetic strategies such as (a) Traube’s synthesis, (b) one-pot synthesis, (c) xanthine-anneleated synthesis, and (d) miscellaneous synthesis were compiled in this review paper. The results obtained from this review paper highlight the significance of various xanthine derivatives as possible leads to the development of new drugs. The data compiled in this review paper could help the medicinal chemist in designing new active compounds from the modification of the already existing compounds in the search for novel drug leads. This report concludes that the various synthetic procedures exemplified in this review paper may serve as a support system for the designing of new molecules with a xanthine scaffold. Thus, we hope that this molecule may serve as the prototype in order to find out more active xanthine derivatives.

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42

Ferretti, Valeria, Loretta Pretto, Mojgan Aghazadeh Tabrizi, and Valerio Bertolasi. "A structural study of new potent and selective antagonists to the A2B adenosine receptor." Acta Crystallographica Section B Structural Science 61, no. 5 (September 23, 2005): 569–76. http://dx.doi.org/10.1107/s0108768105021312.

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Xanthines, including the natural derivatives theophylline and caffeine, are non-selective antagonists of adenosine. They are able to bind with good affinity to all four adenosine-receptor subtypes A1, A2A, A2B and A3. In order to develop new drugs with few side effects, over the last few years many efforts have been devoted to the discovery of new adenosine antagonists with enhanced selectivity properties. The present paper reports the crystal structures of five new xanthinic derivatives, which display different affinities and selectivity properties towards the A2B receptor. Besides the crystallographic study, a structural comparison has been made with the calculated geometry of other xanthinic derivatives which are reported to have similar biological characteristics to understand the structural features controlling their affinity capabilities and selectivity. This structural comparison has been interpreted in the light of a recently published study on the binding of N-benzo[1,3]-dioxol-5-yl-2-[5-(2,6-dioxo-1,3-dipropyl-2,3,6,9-tetrahydro-1H-purin-8-yl)-1-methyl-1-H-pyrazol-3-iloxy]-acetamide to a model of the A2B receptor, which shows the most interesting affinity and selectivity properties.

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&NA;. "Data do not support xanthines for COPD exacerbations." Inpharma Weekly &NA;, no. 1406 (September 2003): 10. http://dx.doi.org/10.2165/00128413-200314060-00023.

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Jacobs, Ayesha, and Francoise M. Amombo Noa. "Co-crystals of vanillic acid with methylated xanthines." Acta Crystallographica Section A Foundations and Advances 71, a1 (August 23, 2015): s461. http://dx.doi.org/10.1107/s2053273315093195.

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Müller, Christa E. "General Synthesis and Properties of 1-Monosubstituted Xanthines." Synthesis 1993, no. 01 (1993): 125–28. http://dx.doi.org/10.1055/s-1993-25814.

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Arnold, Ruth, David Beer, Gurdip Bhalay, Urs Baettig, Stephen P. Collingwood, Sarah Craig, Nicholas Devereux, et al. "8-Aryl xanthines potent inhibitors of phosphodiesterase 5." Bioorganic & Medicinal Chemistry Letters 12, no. 18 (September 2002): 2587–90. http://dx.doi.org/10.1016/s0960-894x(02)00480-8.

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Mikulski, Chester M., Scott Grossman, and Nicholas M. Karayannis. "Zirconium(IV) oxochloride complexes with xanthines and hypoxanthine." Journal of the Less Common Metals 136, no. 1 (December 1987): 41–49. http://dx.doi.org/10.1016/0022-5088(87)90007-5.

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Kim, Donghee, Hwiseok Jun, Hyunseung Lee, Soon-Sun Hong, and Sungwoo Hong. "Development of New Fluorescent Xanthines as Kinase Inhibitors." Organic Letters 12, no. 6 (March 19, 2010): 1212–15. http://dx.doi.org/10.1021/ol100011n.

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Gonzàlez-Jimènez, J., G. Frutos, and I. Cayre. "Fluorescence quenching of human serum albumin by xanthines." Biochemical Pharmacology 44, no. 4 (August 1992): 824–26. http://dx.doi.org/10.1016/0006-2952(92)90422-f.

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Kiesman, William F., Jin Zhao, Patrick R. Conlon, Russell C. Petter, Xiaowei Jin, Glenn Smits, Frank Lutterodt, Gail W. Sullivan, and Joel Linden. "Norbornyllactone-substituted xanthines as adenosine A1 receptor antagonists." Bioorganic & Medicinal Chemistry 14, no. 11 (June 2006): 3654–61. http://dx.doi.org/10.1016/j.bmc.2006.01.021.

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