18623-34-2Relevant articles and documents
Increased in vitro Anti-HIV Activity of Caffeinium-Functionalized Polyoxometalates
Enderle, Ana G.,Bosso, Matteo,Gro?, Rüdiger,Heiland, Magdalena,Bollini, Mariela,Culzoni, María J.,Kirchhoff, Frank,Münch, Jan,Streb, Carsten
, p. 2727 - 2730 (2021)
Polyoxometalates (POMs), molecular metal oxide anions, are inorganic clusters with promising antiviral activity. Herein we report increased anti-HIV-1 activity of a POM when electrostatically combined with organic counter-cations. To this end, Keggin-type cerium tungstate POMs have been combined with organic methyl-caffeinium (Caf) cations, and their cytotoxicity, antiviral activity and mode of action have been studied. The novel compound, Caf4K[β2-CeSiW11O39]×H2O, exhibits sub-nanomolar antiviral activity and inhibits HIV-1 infectivity by acting on an early step of the viral infection cycle. This work demonstrates that combination of POM anions and organic bioactive cations can be a powerful new strategy to increase antiviral activity of these inorganic compounds.
Reactivite du nitrite de sodium. II. Action sur les sels d'iminium heterocycliques. Etude par RMN multinucleaire
Gouesnard, Jean-Paul,Dorie, Jean
, p. 253 - 258 (2007/10/02)
The structure and the electronic delocalisation of various heterocyclic iminium salts - and their precursors - have been studied by 13C and 15N NMR.The 13C and 15N chemical shifts are correlated with the nucleophilicity of the second heteroatom.The observation of δ13C explains satisfactorily the reactivity of heterocyclic iminium salts towards nucleophilic reagents and their catalytic activity as model compounds for thiamine or cocarboxylase.Different products are obtained by the reaction of sodium nitrite - in aqueous or non-aqueous medium - : they have been identified by NMR.The products are those expected and allow the determination of the reaction mechanisms.
ISOMERIZATION AND DEALKYLATION OF METHYLATED XANTHINIUM DERIVATIVES
Muravich-Aleksandr, Kh. L.,Kolesova, M. B.,Pernikova, V. G.,Smirnova, N. V.
, p. 562 - 567 (2007/10/02)
The isomerization or dealkylation of methylated xanthinium derivatives takes place with the participation of nucleophiles and is facilitated in the presence of a sterically hindered configuration.When heated, 7,9-dimethyl- and 1,7,9-trimethylxanthinium salts isomerize to theobromine and caffeine respectively.Under these conditions 3,7,9-trimethyl- and 1,3,7,9-tetramethylxanthinium salts are dealkylated.The 1,7,9- and 3,7,9-trimethylxanthinium betaines are isomerized quantitatively to caffeine.The role of the nucleophile under these conditions is played by the negatively charged fragment in the pyridine part of molecule.An intermolecular mechanism of rearrangement of the 3,7,9-trimethylxanthinium betaine is demonstrated.The sterically overloaded 1,3,8,9-tetramethylxanthine and 1,3,9-trimethyl-8-azaxanthine and not the charged compounds undergo rearrangement.In these cases the nucleophilic center is the doubly bonded N7 atom in the five-membered ring.