Glycosylidene Carbenes. Part 31

Bernet, Bruno; Mangholz, Sissi E.; Briner, Karin; Vasella, A.

doi:10.1002/hlca.200390132

Cited by 14 publications

(8 citation statements)

References 38 publications

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“…Sulfonylation of 1A/1B 95 : 5 with TsCl, naphthalene-2-sulfonyl chloride, and 2,4,6-triisopropylbenzenesulfonyl chloride gave 81% of 2E [19], 83% of 2F, and 64% of 2G, respectively. Similarly, the d-galacto diaziridines 3A/ 3B 95 : 5 and of the d-manno analogues 5A/5B 55 : 45 [2] yielded 4B and 6 in 63 and 55%, respectively.…”

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confidence: 96%

“…[31] [32]), and for C(3) and C(6) of the 1,4-dihydro-1,2,4,5-tetrazine nucleus of 10 (149.7 ppm; cf. [2] [33 ± 35]). The NH signal of 10 is hidden by the signals of the Ph groups.…”

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confidence: 99%

“…C(1) of 17A ± 17D resonates as d at 75.00 ppm ( 2 J( 15 N,H) % 5 Hz). Assuming that only 19B, 22A/22B, 25A/25B, and 28A/28B is attacked by TsCl 8 ), irrespective of the configuration at C(4) or at C (2).…”

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confidence: 99%

“…Acetylation and Sulfonylation of Furanosylidene-Diaziridines. Acetylation of the mannofuranosylidene-diaziridine 30 [2] with Ac 2 O gave 63% of the N-acetylhydrazone 31A and 8% of the 1,2,4,5-tetrazine 32 (Scheme 5). Sulfonylation of 30 led to a similar result, namely to 61% of the N-tosylhydrazone 31B and 11% of 32.…”

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confidence: 99%

“…The tetrazine 32 is probably formed by oxidation of the expected 1,4-dihydro-1,2,4,5-tetrazine. Tosylation of the N-methylated ribofuranosylidene-diaziridines 33A/33B/33C/33D 76 : 4 : 12 : 8 [2] with TsCl and chromatographic separation of the products yielded 44% of a 2 : 1 (E)/ (Z)-mixture of the N-methyl-N-tosylhydrazone 34 and 30% of the ribonolactone 35 Helvetica Chimica Acta ± Vol. 86 (2003) 2498 value of C(1) (149.5 ± 153.5 ppm; Table 3 in Exper.…”

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Glycosylidene Carbenes. Part 32

Mangholz

Briner

Bernet

et al. 2003

Helvetica Chimica Acta

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Dedicated to the memory of Jorge F. Lo¬pez-Herrera 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.Introduction. ± The reactivity of glycosylidene diaziridines has not been wellexplored. Apart from an investigation of their formation [1], with special emphasis on the stereoselectivity of the addition of NH 3 and MeNH 2 to the precursor glyconolactone oxime sulfonates [2], only the oxidation of these diaziridines with iodine and Et 3 N or Me 3 N in MeOH, Et 2 O, or CH 2 Cl 2 [3] to N-unsubstituted-glycosylidene diazirines was investigated. These diazirines have been studied as precursors of glycosylidene carbenes [3 ± 5].The reactivity of 3-alkyldiaziridines has been explored more extensively. Their reaction with electrophiles is strongly influenced by the nature of the electrophile and by the N-substituents. Attack of electrophiles on the diaziridines I leads to diaziridinium ions II (Scheme 1). For R 3 H, deprotonation of II afforded substituted diaziridines III [6 ± 10]. Alternatively, diaziridine ring opening of II led to the hydrazonium ions IV, which were transformed into hydrazones V (R 4 H) [11] [12] and into azomethine imines VI (R 3 H) [13]. Hydrolysis of IV afforded ketones VII and hydrazines VIII [13a] [14] [15]. This transformation to hydrazines constitutes a valuable method for the selective preparation of otherwise hardly accessible N -alkyland N,N'-dialkylhydrazines [16]. The reaction of 1,3,3-trimethyldiaziridine with AcCl led to a 4 : 1 mixture of N-methyl-N'-isopropylidene-acethydrazide and 2-acetyl-1,3,3trimethyldiaziridine [17].Except for the oxidation with I 2 , we found no reaction of glycosylidene diaziridines, nor of any other 3-alkoxydiaziridine with electrophiles. We have examined the reactions of glycosylidene-diaziridines with acylating and sulfonylating reagents, and describe the results of these experiments.Results and Discussion. ± 1. Acylation and Sulfonylation...

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“…[31] [32]), and for C(3) and C(6) of the 1,4-dihydro-1,2,4,5-tetrazine nucleus of 10 (149.7 ppm; cf. [2] [33 ± 35]). The NH signal of 10 is hidden by the signals of the Ph groups.…”

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confidence: 99%

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confidence: 99%

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confidence: 99%

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confidence: 99%

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Glycosylidene Carbenes. Part 32

Mangholz

Briner

Bernet

et al. 2003

Helvetica Chimica Acta

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Asymmetric Synthesis of Three‐ and Four‐Membered Ring Heterocycles with More than One Heteroatom

Lanners

Hanquet

2009

Asymmetric Synthesis of Nitrogen Heterocycles

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Synthesis and Evaluation as Glycosidase Inhibitors of Carbasugar‐Derived Spirodiaziridines, Spirodiazirines, and Spiroaziridines.

Kapferer¹,

Birault²,

Poisson³

et al. 2003

ChemInform

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Carbohydrates Carbohydrates U 0500 Synthesis and Evaluation as Glycosidase Inhibitors of Carbasugar-Derived Spirodiaziridines, Spirodiazirines, and Spiroaziridines. -Various carbosugarderived spirodiaziridines (II) and (V), spirodiazirines [cf. (III)], and spiroaziridines (XIV) and (XV) as well as an amino analogue epivalidamine (XVI) are prepared and tested as inhibitors of αas well as β-glycosidases of different origins. It is shown, however, that all the compounds possess not more than weak inhibiting activity. -(KAPFERER, P.; BIRAULT, V.; POISSON, J.-F.; VASELLA*, A.; Helv. Chim. Acta 86 (2003) 6, 2210-2227; Lab. Org. Chem., ETH, CH-8092 Zuerich, Switz.; Eng.) -Mischke 44-187

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Glycosylidene Carbenes. Part 31

Cited by 14 publications

References 38 publications

Glycosylidene Carbenes. Part 32

Glycosylidene Carbenes. Part 32

Asymmetric Synthesis of Three‐ and Four‐Membered Ring Heterocycles with More than One Heteroatom

Synthesis and Evaluation as Glycosidase Inhibitors of Carbasugar‐Derived Spirodiaziridines, Spirodiazirines, and Spiroaziridines.

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