Fused Pyrimidines. Part 5. Pyrimido[4,5-d]pyrimidine Analogues of Folic Acid

Silica functionalized sulfonic acid catalyzed one-pot synthesis of 4,5,8a-triarylhex-ahydropyrimido[4,5-d]pyrimidine-2,7(1H,3 H)-diones under liquid phase catalysis

“…Typically, a loading of 0.3 mmol g -1 (SO 3 H group) onto the surface of silica was obtained. 4,5, varied concentrations of SiO 2 -SO 3 H and it was found that the catalyst equivalent to 4.5 mol% of SO 3 H was sufficient for the reaction to proceed in quantitative yield. Secondly, to select the appropriate solvent, the reaction with test substrates was carried out in ethanol, toluene and acetonitrile.…”

“…For the preparation of silica functionalized sulfonic acid (SiO 2 -SO 3 H), activated silica was refluxed with trimethoxy (3-sulfanylpropyl)silane in toluene for 24 h to give 3-sulfanylpropylsilica, which was subjected to oxidation with 30% H 2 O 2 in the presence of concentrated Silica Functionalized Sulfonic Acid Catalyzed One-Pot Synthesis of 4,5, sulfuric acid, to give SiO 2 -SO 3 H (Scheme 2) according to the literature method with slight modifications. 12 The SiO 2 -SO 3 H was characterized by infrared spectroscopy, thermal analysis and elemental analysis.…”

“…The IR spectra were recorded using KBr disc on Perkin Elmer FT-IR spectrophotometer and mass spectral data were obtained on ESI-esquires 3000 Bruker Daltonics spectrometer. Thermal analysis was carried out on Perkin Elmer Pyris Diamond Thermal Analyzer with heating rate of 10 °C min -1 and elemental analysis was carried out on Silica Functionalized Sulfonic Acid Catalyzed One-Pot Synthesis of 4,5, Leco-CHNS-932 elemental analyzer manufactured by Leco Corporation, USA Australia. The reactions were monitored qualitatively by TLC.…”

“…Recently, pyrimido [4,5-d]pyrimidine analogues of folic acid were found to show antitumor activity. 5 Thus, the preparation of this heterocyclic nucleus has attracted great attention. Most methods for the preparation of pyrimido [4,5-d]pyrimidines are based on the manipulation of uracils.…”

Synthesis and antimicrobial activity of new triazolopyrimidinecarbonitrile derivatives

“…Many compounds containing the pyrimidine nucleus are of significant biological importance and are used as antibacterial, [1][2][3][4][5] antifungal, 6,7 antimalarial, 8 antitumour, [9][10][11] antiviral, [12][13][14][15] antiinflammatory [16][17][18] or antihypertensive [19][20][21] agents. In this work, we synthesized some new 3,4,5-trimethoxyphenyltriazolopyrimidinecarbonitrile derivatives in the hope of obtaining new products of superior biological activity.…”