Design of compounds that can protect efficiently against γ-rays irradiation is a great challenge. An ionizing event can cause variety of DNA damage scenarios leading to mutagenesis, cell death. 2-(1-Naphthylmethyl)-2-imidazoline (naphazoline, NP) is a drug belonging to the vasoregulator class, which was shown to be a very interesting compound in radioprotection. In order to highlight the NP radioprotective activity, a comparison of its ability to protect DNA against either γ-irradiation or radicals generated by Fenton's reaction was made. Results show that NP inhibits efficiently the generation of DNA single-strand breaks and that NP is a potent radioprotector and also an hydroxyl radical scavenger. To cite this article: C.

A series of organosilicon and organogermanium compounds derived from cysteamine, methylcysteamine and 2-[1-(1-naphthyl)ethyl]-2-imidazoline have been prepared and their radiopharmacological properties (radioprotective activity and toxicity) have been determined in mice. A number of these new organometallic derivatives have been found to possess radioprotective activity.We have also noted a notable decrease of the toxicity and a fairly large increase in the radioprotective activity in comparison with the unsubstituted organic molecules.

RÉSUMÉDans ce travail, nous avons synthétisé des phosphorothioates dérivés de la 2-(1-naphthylméthyl)-2-imidazoline et de la 2-[1-(1-naphthyl)éthyl]-2-imidazoline afin d'évaluer, in vivo chez la souris, leur degré de protection contre les effets des rayonnements γ. Tous ces composés ont montré une activité radioprotectrice remarquable (facteur de réduction de dose compris entre 1,5 et 1,9) ce qui les classent parmi les plus actifs actuellement connus dans le domaine de la radioprotection chimique. Ces composés peuvent également présenter un intérêt dans le domaine des traitements de chimio-et de radio-thérapie.ABSTRACT New phosphorothioates derived from naphthylmethylimidazoline and naphthylethylimidazoline: application in chemical radioprotection.In this work, we report the radiopharmacological study (radioprotective activity, toxicity) of new phosphorothioates derived from 2-(1-naphthylmethyl)-2-imidazoline and 2-[1-(1-naphthyl)ethyl]-2-imidazoline. The radioprotective efficacy against γ-rays of these organophosphorus compounds was evaluated in vivo. All these derivatives have shown a dose reduction factor between 1.5 and 1.9 which traduce their excellent radioprotective activity. These compounds should present an interest in the chimio-and radiotherapy treatments.

A number of organosilicon and organogermanium derivatives of N-substituted 2-[1-(1-naphthyl)-ethyl]-2-imidazoline have been reported and the toxicity of these compounds has been determined in mice. In this paper we report the evaluation of the radioprotective activity of new sila-and germadithioacetals derived from N-substituted 2-[1-(1-naphthyl)ethyl]-2-imidazoline.