Dedicated to
Glycosylidene Carbenes. Part 32 : Reaction of Glycosylidene Diaziridines with Acylating and Sulfonylating Agents
✍ Scribed by Sissi E. Mangholz; Karin Briner; Bruno Bernet; Andrea Vasella
- Publisher
- John Wiley and Sons
- Year
- 2003
- Tongue
- German
- Weight
- 235 KB
- Volume
- 86
- Category
- Article
- ISSN
- 0018-019X
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✦ Synopsis
Abstract
Acylation and sulfonylation of the N,N′__‐__unsubstituted glucosylidenespirodiaziridines 1A/1B 95 : 5 with Ac~2~O, BzCl, FmocCl, TsCl, (naphthalen‐2‐yl)sulfonyl, and (2,4,6‐triisopropylphenyl)sulfonyl chloride, and concomitant rearrangement gave the acylated and sulfonylated gluconolactone hydrazones 2B–2G in 40–83% yield (Scheme 2). Similarly, the galacto and manno analogues 3A/3B 95 : 5 and 5A/5B 55 : 45 and the mannofuransoylidene‐diaziridine 30 were acetylated and tosylated to give 4A, 4B, 6, 31A, and 31B (55–73% yield; Schemes 2 and 5). ^15^N‐Labelling of 11A/11B and 14A/14B showed that the pseudoequatorial NH of the gluco diaziridines 1 and the pseudoaxial NH of the galacto diaziridines 3 were preferentially acetylated and tosylated (Scheme 3). Sulfonylation of the N‐methylated diaziridines 19A/19B 72 : 28, 22A/22B 85 : 15, 25A/25B 85 : 15, 28A/28B 80 : 20, and 33A/33B/33C/33D 76 : 4 : 12 : 8 yielded the N‐methyl‐N‐tosylglyconolactone hydrazones 20, 23, 26, 29, and 34 (44–66%; Schemes 4 and 5). The methylated N‐atom of the diaziridines proved more reactive, irrespective of the configuration at C(2) and C(4). The products were readily hydrolysed to glyconolactones.
📜 SIMILAR VOLUMES
A new approach towards the synthesis of glycosides based upon a (formal) insertion of glycosylidene carbenes into 0-H bonds is presented. The synthesis and characterization of the glycosylidene-derived diazirines 25-28, precursors of glycosylidene carbenes, are described. The diazirines were prepare
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## Abstract C‐acyl‐N‐(3‐phenyl‐5‐pyrazolyl)hydrazonoyl chlorides **1a,b** react with potassium thiocyanate and potassium selenocyanate to give 5‐acyl‐2,3‐dihydro‐2‐imino‐3‐(3′‐phenyl)pyrazol‐5′‐yl)‐1,3,4‐thiadiazoles **2a,b** and 5‐acetyl‐2,3‐dihydro;‐2‐imino‐3‐(3′‐phenyl)pyrazol‐5′‐yl)‐1,3,4‐selen