Novel 2-Thioxanthine and Dipyrimidopyridine Derivatives: Synthesis and Antimicrobial Activity.

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Novel 2-Thioxanthine and Dipyrimidopyridine Derivatives: Synthesis and Antimicrobial Activity.

Several fused imidazolopyrimidines were synthesized starting from 6-amino-1-methyl-2-thiouracil (1) followed by nitrosation, reduction and condensation with different aromatic aldehydes to give Schiff's base. The dehydrocyclization of Schiff's bases using iodine/DMF gave Compounds 5a-g. The methylation of 5a-g using a simple alkylating agent as dimethyl sulfate ((CH3)2SO4) gave either monoalkylated imidazolopyrimidine 6a-g at room temperature or dialkylated derivatives 7a-g on heating 6a-g with ((CH3)2SO4). On the other hand, treatment of 1 with different aromatic aldehydes in absolute ethanol in the presence of conc. hydrochloric acid at room temperature and/or reflux with acetic acid afforded bis-5,5́-diuracylmethylene 8a-e, which cyclized on heating with a mixture of acetic acid/HCl (1:1) to give 9a-e. Compounds 9a-e can be obtained directly by refluxing of Compound 1 with a mixture of acetic acid/HCl. The synthesized new compounds were screened for antimicrobial activity, and the MIC was measured.

Synthesis and in vitro study of pyrimidine-phthalimide hybrids as VEGFR2 inhibitors with antiproliferative activity.

Aim: Thalidomide, a once notorious sedative, is now clinically used as an antitumor agent. We aimed to use it as a lead compound for designing pyrimidine-phthalimide hybrids. Materials & methods: Nucleophilic substitution reaction of thalidomide analog 4 with primary and/or secondary aliphatic amines afforded pyrimidine-phthalimide hybrids 5a-g, 6 and 7a-d. Results & conclusion: Compound 7c showed high antiproliferative activity against four cell lines: HepG-2 (IC50: 7.86 ± 0.5 µM), MCF-7 (IC50: 2.77 ± 0.1 µM), HCT-116 (IC50: 5.73 ± 0.4 µM) and PC-3 (IC50: 8.32 ± 0.5 µM), with selective cytotoxicity for WI-38 (IC50: 43.2 ± 2.56 µM). 7c arrested MCF-7 cells at S phase of the cell cycle and increased the total apoptotic cells by 50-fold. 7c inhibited VEGFR2 in vitro (IC50: 0.130 ± 0.02 µM). 7c was capable of binding at the VEGFR2 binding site, forming hydrogen bond interactions with Asp1046 and Glu885 in a similar way to sorafenib.

Design, synthesis and antitumor activity of novel pyran-functionalized uracil derivatives: docking studies.

Aim: Synthesis of novel pyran-based uracils that may have potent antitumor activity against hepatocellular carcinoma HepG2 and ovarian cancer SKOV3 cell lines. Materials & methods: Novel pyran-based uracils were synthesized and their anticancer activity was assessed using methyl thiazolyl tetrazolium and wound-healing assays to detect their cytotoxicity and their antiproliferative and antimigratory activities. Results: Compounds 3, 5, 6, 7, 8, 9, 10, 11 and 13 significantly inhibited cell proliferation of the HepG2 cell line. Compounds 7, 8, 9 and 13 significantly inhibited the proliferation of SKOV3 cells, which was also proven through docking studies with topoisomerase I. Conclusion: The molecular docking analysis revealed that 7 and 9 are two major compounds found to possess higher degrees of interaction with DNA gyrase.