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WOS: 000247702200014, PubMed ID: 17145131, In the presented work, a-benzoin oxime immobilized SP70 chelating resin was synthesized for separation and preconcentration of Pb(II), Cd(II), Co(II) and Cr(III). The optimization procedure for analytical parameters including pH, eluent type, flow rate, etc. was examined in order to gain quantitative recoveries of analyte ions. The effects of foreign ions on the recoveries of studied metal ions were also investigated. The detection limits Q(T) were found to be 16.0, 4.2, 1.3, 2.4 mu g L-1 for Pb, Cd, Co and Cr, respectively. The preconcentration factor was 75 for Ph, 100 for Cd, Co and Cr. The optimized method was validated with certified reference materials and successfully applied to the waters, crops and pharmaceutical samples with good results (recoveries greater than 95%, R.S.D. lower than 10%). (c) 2006 Elsevier B.V. All rights reserved.

Durch Acylierung der N-unsubstituierten 1,3-Thiazinderivate 3 und 6 mit Saurechloriden werden die neuartigen N-Acyl-2-thioxo-3,4-dihydro-1,3-thiazin-4-one 4 bzw. die N-Acyl-tetrahydro-1,3-thiazin-2,4-dione 7 dargestellt. Ihre Eigenschaften werden mit denen bereits bekannter N-Acylthiazinderivate verglichen. 1,3-Thiazines, XXV: Transacylating Derivatives of N-Acyltetrahydro- and N-Acyldihydro-1,3-thiazine Novel N-acyl-2-thioxo-3,4-dihydro-1,3-thiazine-4-ones 4 and N-acyl-tetrahydro-1,3-thiazine-2,4-diones 7 were preparee by acylation of the N-unsubstituted 1,3-thiazine derivatives 3 and 6 with acid chlorides. Their characteristics are compared with those of known N-acylthiazine derivatives.

Ein neuer, fur N-Arylverbindungen mit guten Ausbeuten verlaufender Syntheseweg fur N-substituierte Tetrahydro-1,3-thiazin-2-thione 5, bestehend in der Schwefelkohlenstoffspaltung von N,N'-disubstituierten 2-Imino-tetrahydro-1,3-thiazinen 3 zu 5 und Isothiocyanaten 6, wird vorgestellt. 1,3-Thiazines, XV: New Synthetic Route to N-Substituted Tetrahydro-1,3-thiazine-2-thiones. A new synthetic route to N-substituted tetrahydro-1,3-thiazine-2-thiones 5 giving good yields for N-aryl compounds is reported. It consists of carbon disulfide cleavage of N,N'-disubstituted 2-iminotetrahydro-1,3-thiazines 3 which leads to 5 and the isothiocyanates 6.

Die Synthese neuartiger N-Acyl-tetrahydro-1,3-thiazin-2-thione 3 wird beschrieben. Es werden transacylierende Eigenschaften gegenuber nucleophilen Verbindungen gefunden. On 1,3-Thiazines, XX: Transacylating N-Acyltetrahydro-1,3-thiazine-2-thiones The synthesis of novel N-acyltetrahydro-1,3-thiazine-2-thiones 3 with transacylating activity towards nucleophilic compounds is described.

Die Tetrahydro-1,3-thiazin-2-thione 1 wurden mittels Thionylchlorid in die teilweise isolierbaren 2,2-Dichlor-tetrahydro-1,3-thiazine 2 uberfuhrt, die bei der Hydrolyse die Tetrahydro-1,3-thiazin-2-one 3, bei der Umsetzung mit Stickstoffbasen mit primaren Aminogruppen die 2-Iminotetrahydro-1,3-thiazine 4 ergaben. Durch Stickstoffabspaltung aus den 2-Nitrosoiminotetrahydro-1,3-thiazinen 6 gelangt man ebenfalls zu den 2-Oxo-thiazinen 3, die zu den Sulfonstrukturen 7 oxidiert werden konnten. Investigations of 1,3-Thiazines, XXIII: Novel Transformations of Tetrahydro-1,3-thiazine-2-thiones with Thionyl Chloride The tetrahydro-1,3-thiazine-2-thiones 1 were transformed into the 2,2-dichlorotetrahydro-1,3-thiazines 2 some of which could be isolated. They react with water to yield the tetrahydro-1,3-thiazine-2-ones 3 and with primary nitrogen bases to yield the 2-iminotetrahydro-1,3-thiazines 4. The 2-(nitrosoimino)tetrahydro-1,3-thiazines 6 split off nitrogen to yield 3. Compounds of type 3 can be oxidized to the sulfones 7.

Das Umsetzungsprodukt von Prop-2-inylamin und Schwefelkohlenstoff wurde entgegen fruheren Befunden als 5-Methylen-1,3-thiazolidin-2-thion (3a) identifiziert und dieses mit Alkylhalogeniden, Acyl-, Carbamoyl- und Thiocarbamoylchloriden umgesetzt. Die Strukturzuordnung der N- bzw. S-Substitutionsprodukte sowie die Tautomerieverhaltnisse wurden durch 13C-NMR-Spektroskopie geklart. Alkylation, Acylation, and Carbamoylation Products of 5-Methylene-1,3-thiazolidine-2-thione The reaction product of prop-2-inylamine and carbon disulfide was contrary to earlier results identified as 5-methylene-1,3-thiazolidine-2-thione (3a). This was reacted with alkyl halides, acyl, carbamoyl, and thiocarbamoyl chlorides. The structures of the N- respective S-substitution products and the tautomeric relations were confirmed by 13C NMR spectroscopy.

Die N-unsubstituierten 1,3-Thiazinderivate 1–3 werden durch Carbamoylchloride oder Thiocarbamoylchloride in Gegenwart von Triethylamin oder Natriumhydrid zu den N-Carbamoyl- bzw. N-Thiocarbamoyl-1,3-thiazinderivaten 5–9 umgesetzt. 1,3-Thiazines, XXVI: Novel N-Carbamoyl- and Thiocarbamoyl-2-thioxo-1,3-thiazine Derivatives The N-unsubstituted 1,3-thiazine derivatives 1–3 were transformed into the N-carbamoyl- or N-thiocarbamoyl-1,3-thiazine derivatives 5–9 by carbamic acid chlorides or thiocarbamic acid chlorides in the presence of triethylamine or sodium hydride.