No abstract

Pyrazolopyranopyrimidines 6aÐc and 8aÐc were prepared from the reaction of compounds 4aÐc or 7aÐc with methylamine or ammonium hydroxide solutions. Treatment of compounds 6aÐc or 8aÐc with 2-chloroethyl methyl ether afforded their corresponding acyclonucleosides 9aÐc or 10aÐc, respectively, as a new class of acyclonucleosides. All prepared compounds were tested as anti-inflammatory agents and some of them revealed moderate to potent antiinflammatory activity.

No abstract

No abstract

Recently, nano-macro dual-porous, three-dimensional (3D) glass structures were developed for use as bioscaffolds for hard tissue regeneration, but there have been concerns regarding the interconnectivity and homogeneity of nanopores in the scaffolds, as well as the cytotoxicity of the environment deep inside due to limited fluid access. Therefore, mercury porosimetry, nitrogen absorption, and TEM have been used to characterize nanopore network of the scaffolds. In parallel, viability of MG 63 human osteosarcoma cells seeded on scaffold surface was investigated by fluorescence, confocal and electron microscopy methods. The results show that cells attach, migrate and penetrate inside the glass scaffold with high proliferation and viability rate. Additionally, scaffolds were implanted under the skin of a male New Zealand rabbit for in vivo animal test. Initial observations show the formation of new tissue with blood vessels and collagen fibers deep inside the implanted scaffolds with no obvious inflammatory reaction. Thus, the new nano-macro dual-porous glass structure could be a promising bioscaffold for use in regenerative medicine and tissue engineering for bone regeneration.

Some new thiopyrimidine acyclic nucleosides and thioglycoside derivatives 3a-c, 4a-c, 6a,b, and 7a,b were synthesized. The cytotoxicity and antitumor evaluation of all prepared compounds have been tested in vitro against Ehrlich's ascites carcinoma cell line and their activity against glutathione peroxidase and catalase were reported. The role of the prepared compounds as free radical regulators and the therapeutic antitumor effect of a balanced generation of free radicals are discussed. Compounds 2, 3b, 3c, 4a, and 4c inhibited significantly in a dose dependent manner the growth of Ehrlich ascites carcinoma cells while the other compounds did not show any antitumor activity even at higher concentrations.

Several derivatives containing the thieno [2,3-d]pyrimidine system were prepared starting from 2-amino-4,5-dihydronaphtho[2,1-b]thiophene-1-carbonitrile (1). In particular, the synthesis and structure characterization of 8,9-dihydronaphtho-[1 ,2 :4,5]thieno [3,2-e] [1,2,4]triazolo [4,3-c]pyrimidine derivatives 13-16 and their isomerization to 8,9-dihydronaphtho[1 ,2 :4,5]thieno [3,2-e]

Some cyclic and acyclic nucleosides of thieno[2,3-d]-pyrimidine derivatives were synthesized via the reaction of compounds 1 and 2 or 3 and 4 with 2-chloroethyl methyl ether or 2,3,4, 6-tetra-O-acetyl-alpha-D-glucopyranosyl bromide. Nucleosides 9, 10, 15, and 16 were tested as antiviral agents against herpes simplex virus type-1 (HSV-1) and hepatitis-A virus (HAV). Compound 15 showed the highest effect on HSV-1 than the other three compounds, while the four tested compounds did not show any activity against HAV.