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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 2B2G 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.


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