Srinivas G, Prabhakar G, Unny V K P, Sudhakar K, Mukkanti K, Choudary B M
Radiolabelling Department, Ogene Systems (I) Pvt. Ltd, #11-6-56, GSR Estates, Balanagar, Hyderabad, 500037, Andhra Pradesh, India.
J Labelled Comp Radiopharm. 2013 Jun 30;56(8):382-4. doi: 10.1002/jlcr.3053. Epub 2013 Jun 18.
In this paper is reported a novel reaction scheme for the no-carrier-added submicromolar scale radiosynthesis of [S-methyl-(14)C]-florfenicol that has been newly designed, developed and employed by us successfully. The [(14)C]-product was obtained in an overall radiochemical yield of 30% based on [(14)C]-methyl iodide taken for the reaction with a radiochemical purity of more than 96%. The specific activity of the product was ~50 mCi (1.85 GBq)/mmol. Chlorosulfonation of compound I was followed by sodium salt formation in situ and it was succeeded by the introduction of [(14)C]-methyl group by coupling with [(14)C]-CH3 I. Subsequently, the oxazolidin-2-one protecting group was opened up by a reaction with sulfuric acid in dioxane and later, the amino group was dichloroacetylated with methyl-2,2-dichloroacetate in triethylamine to obtain [S-methyl-(14)C]-florfenicol.
本文报道了一种新的反应方案，用于我们新设计、开发并成功应用的无载体添加的亚微摩尔级[ S-甲基-(14)C ]-氟苯尼考的放射性合成。基于用于反应的[ (14)C ]-甲基碘，以超过96%的放射化学纯度获得了放射化学总产率为30%的[ (14)C ]-产物。产物的比活度约为50 mCi (1.85 GBq)/mmol。化合物I经氯磺化后原位形成钠盐，接着通过与[ (14)C ]-CH3 I偶联引入[ (14)C ]-甲基。随后，通过与二氧六环中的硫酸反应打开恶唑烷-2-酮保护基，之后，在三乙胺中用甲基-2,2-二氯乙酸酯将氨基二氯乙酰化，得到[ S-甲基-(14)C ]-氟苯尼考。
