5′-Norcarbocyclic nucleoside analogs

Discovery of an L-like Configuration for 3'-Fluoro-5'-norcarbonucleoside Phosphonates as Potent Anti-HIV Agents

Recently, we reported the racemic synthesis of 3'-fluoro-5'-norcarbocyclic nucleoside phosphonates bearing adenine as the heterocyclic base. For this study, to evaluate the antiviral activity of each enantiomer, we synthesized both enantiomers, as well as their corresponding bis(POM) prodrugs. Anti-HIV-1 evaluation against the LAI strain and clinically NRTI-resistant HIV-1 strains are presented. The activities against these different strains show that the activities of bis(POM) prodrug (-)-9 are equivalent or even superior to those of (R)-PMPA.

Uracil-Containing Heterodimers of a New Type: Synthesis and Study of Their Anti-Viral Properties

Widespread latent herpes viral infections within a population can lead to the development of co-infections in HIV-infected patients. These infections are not particularly dangerous for healthy individuals and often occur with minimal symptoms, but for those who are immunocompromised, these infections can accelerate the acute phase of HIV infection and AIDS. Thus, the idea of designing compounds that could combine activity against HIV and co-infections would seem promising. In that regard, eleven compounds were synthesized that represent conjugates of non-nucleoside HIV reverse transcriptase inhibitors and nucleoside inhibitors of the herpes family viruses with the hope that these novel heterodimers will result in dual activity against HIV and concomitant herpes virus infections.

Antifungal activity of 1'-homo-N-1,2,3-triazol-bicyclic carbonucleosides: A novel type of compound afforded by azide-enolate (3+2) cycloaddition

The first report of 1'-homo-N-1,2,3-triazol-bicyclic carbonucleosides (7a and 7b) is described herein. Azide-enolate (3+2) cycloaddition afforded the synthesis of this novel type of compound. Antifungal activity was evaluated in vitro against four filamentous fungi (Aspergillus fumigatus, Trichosporon cutaneum, Rhizopus oryzae and Mucor hiemalis) as well as nine species of Candida spp. as yeast specimens. These pre-clinical studies suggest that compounds 7a and 7b are promising candidates for complementary biological studies due to their good activity against Candida spp.

The investigation of the cellular electrophysiological and antiarrhythmic effects of a novel selective sodium-calcium exchanger inhibitor, GYKB-6635, in canine and guinea-pig hearts

The sodium-calcium exchanger (NCX) is considered as the major transmembrane transport mechanism that controls Ca²⁺ homeostasis. Its contribution to the cardiac repolarization has not yet been directly studied due to lack of specific inhibitors, so that an urgent need for more selective compounds. In this study, the electrophysiological effects of GYKB-6635, a novel NCX inhibitor, on the NCX, L-type calcium, and main repolarizing potassium currents as well as action potential (AP) parameters were investigated. Ion currents and AP recordings were investigated by applying the whole-cell patch clamp and standard microelectrode techniques in canine heart at 37 °C. Effects of GYKB-6635 were studied in ouabain-induced arrhythmias in isolated guinea-pig hearts. At a concentration of 1 μmol/L, GYKB significantly reduced both the inward and outward NCX currents (57% and 58%, respectively). Even at a high concentration (10 μmol/L), GYKB-6635 did not change the I_CaL, the maximum rate of depolarization (dV/dt_max), the main repolarizing K⁺ currents, and the main AP parameters. GYKB-6635 pre-treatment significantly delayed the time to the development of ventricular fibrillation (by about 18%). It is concluded that GYKB-6635 is a potent and highly selective inhibitor of the cardiac NCX and, in addition, it is suggested to also contribute to the prevention of DAD-based arrhythmias.

5′-Norcarbocyclic analogues of furano[2,3-d]pyrimidine nucleosides

5′-Norcarbocyclic analogues of furano[2,3-d]pyrimidine nucleosides as well as 5-bromo and 5-iodouracil derivatives were synthesized to evaluate their potential antitumor activity. The halogenated derivatives display no cytotoxicity with respect to all tested cells: KB-3-1 (human epidermoid carcinoma), HeLa (human cervical epithelioid carcinoma), HuTu-80 (human duodenal cancer), B16 (mouse melanoma), and MDCK (normal epithelial). The cytotoxicity of the non-halogenated furano[2,3-d]pyrimidine derivatives increases with the lengthening of the alkyl chain of the substituent from 45 to 60 μm for octyl to from 3 to 10 μm for dodecyl.

5-Arylaminouracil Derivatives: New Inhibitors of Mycobacterium tuberculosis

Three series of 5-arylaminouracil derivatives, including 5-(phenylamino)uracils, 1-(4'-hydroxy-2'-cyclopenten-1'-yl)-5-(phenylamino)uracils, and 1,3-di-(4'-hydroxy-2'-cyclopenten-1'-yl)-5-(phenylamino)uracils, were synthesized and screened for potential antimicrobial activity. Most of compounds had a negative effect on the growth of the Mycobacterium tuberculosis H37Rv strain, with 100% inhibition observed at concentrations between 5 and 40 μg/mL. Of those, 1-(4'-hydroxy-2'-cyclopenten-1'-yl)-3-(4‴-hydroxy-2‴-cyclopenten-1‴-yl)-5-(4″-butyloxyphenylamino)uracil proved to be the most active among tested compounds against the M. tuberculosis multidrug-resistant strain MS-115 (MIC90 5 μg/mL). In addition, the thymidylate kinase of M. tuberculosis was evaluated as a possible enzymatic target.