title: A novel no-carrier-added submicromolar scale radiosynthesis of [S-methyl-14C]-florfenicol.
abstract: 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.
authors.affiliation: Radiolabelling Department, Ogene Systems (I) Pvt. Ltd, #11-6-56, GSR Estates, Balanagar, Hyderabad, 500037, Andhra Pradesh, India.
authors.forename: G
authors.initials: G
authors.lastname: Srinivas
authors.forename: G
authors.initials: G
authors.lastname: Prabhakar
authors.forename: V K P
authors.initials: VK
authors.lastname: Unny
authors.forename: K
authors.initials: K
authors.lastname: Sudhakar
authors.forename: K
authors.initials: K
authors.lastname: Mukkanti
authors.forename: B M
authors.initials: BM
authors.lastname: Choudary
mesh_terms: D002250:Carbon Radioisotopes / Q000737:chemistry; D060326:Chemistry Techniques, Synthetic / Q000379:methods; D007553:Isotope Labeling / Q000379:methods; D013839:Thiamphenicol / Q000031:analogs & derivatives* / Q000138:chemical synthesis
chemical_list: D002250:Carbon Radioisotopes; C035534:florfenicol; D013839:Thiamphenicol
keywords: S-methylation; [14C]-methyl iodide; radioisotopically labeled florfenicol; radiosynthesis of [S-methyl-14C]-florfenicol