Publications by authors named "Umberto Ciambecchini"

We describe the role of formamide, a product of the hydrolysis of hydrogen cyanide, as precursor of several components of nucleic acids under prebiotic conditions. When formamide is heated in the presence of montmorillonites, the efficient one-pot synthesis of purine, adenine, cytosine, and uracil is obtained. Along with these nucleobases, several components of the inosine pathway are obtained: 5-aminoimidazole-4-carboxamide, 5-formamidoimidazole-4-carboxamide and hypoxanthine.

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A novel one-pot TiO2-catalyzed synthesis of nucleobases and acyclonucleosides from formamide is reported. Since formamide can be formed under prebiotic conditions, these reactions have implications for the origin of life. While a number of purine derivatives have been found as products of non-TiO2-catalyzed reactions, important compounds that would not otherwise occur (namely, thymine, 5-hydroxymethyluracil, and acyclonucleosides) are formed in acceptable yields by TiO2-catalyzed reactions.

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Purine and pyrimidine derivatives, antioxidants, fusion inhibitors, statins, prostaglandins, antibiotic nucleosides, inhibitors of Ca(2+) homeostasis, carbohydrate derivatives, antisense polynucleotides and chimeras, are described as inhibitors of parainfluenza-1 (Sendai) viral infections.

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New 6-[(2'-dialkylamino)ethyl]-4(3H)-pyrimidinones were prepared by a multistep procedure starting from acetone dicarboxylic acid diethyl ester and urea derivatives. These compounds were used as starting materials to obtain 4-N,N-dialkyl-6-vinyl-pyrimidine derivatives by an unprecedented tandem C-6 side chain Hofmann-like elimination/C-4 pyrimidinone substitution. Among the new derivatives obtained, various compounds show anti-Rubella activity.

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