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A new tetrahydrated form of sodium naproxen

Piera Di Martino1, Christine Barthélémy, Etienne Joiris

  • 1Dipartimento di Scienze Chimiche, Università di Camerino, Via S. Agostino, Camerino, Italy. piera.dimartino@unicam.it

Journal of Pharmaceutical Sciences
|September 9, 2006
PubMed

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An element composed of atoms that readily lose electrons (a metal) can react with an element composed of atoms that readily gain electrons (a nonmetal) to produce ions through complete electron transfer. The compound formed by this transfer is stabilized by the electrostatic attractions (ionic bonds) between the oppositely charged ions.
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Secondary amines react with nitrous acid to form N-nitrosamines, as depicted in Figure 1. Nitrous acid, a weak and unstable acid, is formed in situ from an aqueous solution of sodium nitrite and strong acids, such as hydrochloric acid or sulfuric acid, in cold conditions. In the presence of an acid, the nitrous acid gets protonated. The subsequent loss of water results in the formation of the electrophile known as nitrosonium ion.