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Sulfonamide linker

Scheme 28 Activation and cleavage of the Ellman sulfonamide linker. Scheme 28 Activation and cleavage of the Ellman sulfonamide linker.
Scheme 2. Ellmans sulfonamide linker allowed the (DIPEA, N-ethyl-N,N-diisopropylamine DTT, synthesis of the acid- and base-labile glycopeptide dithiothreitol EDT, ethanedithiol GnHCI, thioester 6, which was used for the Native guanidinium hydrochloride NMP, N-methyl-... Scheme 2. Ellmans sulfonamide linker allowed the (DIPEA, N-ethyl-N,N-diisopropylamine DTT, synthesis of the acid- and base-labile glycopeptide dithiothreitol EDT, ethanedithiol GnHCI, thioester 6, which was used for the Native guanidinium hydrochloride NMP, N-methyl-...
Undoubtedly, the most important stereochemical feature is chirality. The [2]-rotaxane depicted schematically in Figure 2.12a is made with a macrocycle and a dumbbell that are not themselves chiral but oriented by appropriate substitution patterns on these components. Vogtle and co-workers described cycloenantiomeric rotaxanes that are based on the amide templating functionality (Figure 2.13).36 Racemic [2]-rotaxane 34 was synthesized in 20% yield by reaction of unsymmetrical acid dichloride 32 with trityl aniline 33 in the presence of macrocycle 31. The object and its mirror image are created by different sequences of the amide and sulfonamide linkers in both the dumbbell and the macrocyclic component. If the order of the atoms within the dumbbell is examined, in one enantiomer the sulfonamide nitrogen atom is... [Pg.137]

Hirayama et al. [90] made the efforts to discover FXa inhibitors, containing carboxamide and sulfonamide linkers (36-41). From their data Eq. 22 was formulated [72], where MRb is the most significant term followed by the indicator variable I-NAPH, used for the presence of a naphthyl group in the compound. Group B is indicated in the structures. [Pg.30]

Palomo JM, Lumbierres M, Waldmann H. Efficient solid-phase hpopeptide synthesis employing the Ellman sulfonamide linker. Angew. Chem. 2006 118 477-481. [Pg.923]

Scheme 6 Strategy for peptide thioester synthesis by intramolecular NS acyl shift on sulfonamide linker... Scheme 6 Strategy for peptide thioester synthesis by intramolecular NS acyl shift on sulfonamide linker...
The Ellman sulfonamide linker is stable tmder acid or basic conditions. It can be selectively alkylated with haloacetonitriles, and then becomes susceptible to nucleophilic attack, leading to release of the peptide from the solid support (Scheme 5a)... [Pg.150]

However, classical cleavage with a solution of methanol and DMAP leads to significant racemerization of cysteine. An alternative approach was to release the peptide from the solid support using H-Cys(Far)-OMe as a nucleophile with microwave irradiation for 10 min. Peptide corresponding to N-Ras protein C-terminus 13 was synthesized using Ellman sulfonamide linker strategy as shown in Scheme 5b (dotted line) [59, 60]. [Pg.151]

Triola, G., Gerauer, M, Gormer, K, Brunsveld, L., and Waldmann, H. (2010) SoUd-phase synthesis of Upidated ras peptides employing the oilman sulfonamide linker. Chem. Eur. /., 16, 9585-9591. [Pg.121]

FIGURE 2.10 A solid-phase total synthesis of kahalalide A. The Kenner safety-catch sulfonamide linker was employed for backbone amide attachment. After assembly of the hnear peptide, safety-catch activation resulted in macrocyclative cleavage from the resin. [Pg.49]

In such linkers, the latent bond requires activation before cleavage can occur. Many of the linker units discussed elsewhere in this chapter could be considered safety-catch linker units. For example, photolytic activation described in Section 1.2.4 and cyclorelease discussed in Section 1.2.2 are essentially safety-catch strategies. This section, however, will concentrate on synthetic activation. The first example of such an approach was a sulfonamide linker reported by Kenner et al. in 1971. The sulfonamide 7 is stable to both acidic and basic conditions, making it synthetically valuable. However, alkylation of the nitrogen with, for example, diazomethane or iodoacetonitrile, gave 8, from which substrates (e.g., carboxylic acids 9) could be cleaved under nucleophilic conditions (Scheme 1.4). [Pg.24]

Ellman s sulfonamide linker has also been used as the safety-catch-type linker for the synthesis of the glycodendrimer to enhance the interaction with the glycan receptors and lectins by the glycan multivalency effects (Scheme 16.9). Thus, the hexavalent a-man-nose introduced on the sohd-supported dendrimer 25 was activated for the nucleophihc... [Pg.495]

For Solution A, mix together 8 g of phenol, 0.5 g of ninhydrin, and 10 mL of EtOH, and store the solution in a scintillation vial. In a separate scintillation vial, mix together 0.013 g of KCN and 10 mL of pyridine. This is Solution B. In a small test tube, place several beads (approx 1 mg) along with approx 0.1 mL of Solution A and 0.1 mL of Solution B. Mix and heat the contents of the test tube to 70°C with a sand bath. A positive ninhydrin test for the nonreacted amino methylated resin gives a deep blue color while the sulfonamide linker 2 gives a pale red color. [Pg.101]

Fill each of 40 Teflon-coated reaction vessels with 0.2 g (0.025 mmol) of dry sulfonamide linker 2 (0.125 mmol/g) and 0.03 g (0.24 mmol) of DMAP and seal the vessels under nitrogen with Teflon-coated rubber septa (see Note 16). [Pg.102]


See other pages where Sulfonamide linker is mentioned: [Pg.560]    [Pg.153]    [Pg.202]    [Pg.16]    [Pg.231]    [Pg.247]    [Pg.474]    [Pg.918]    [Pg.919]    [Pg.438]    [Pg.443]    [Pg.513]    [Pg.26]    [Pg.250]    [Pg.543]    [Pg.579]    [Pg.91]    [Pg.322]    [Pg.125]    [Pg.110]    [Pg.115]    [Pg.149]    [Pg.194]    [Pg.194]    [Pg.48]    [Pg.276]    [Pg.546]    [Pg.2924]    [Pg.496]    [Pg.96]    [Pg.100]    [Pg.101]   
See also in sourсe #XX -- [ Pg.24 , Pg.495 , Pg.496 ]




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Ellman sulfonamide linker

Safety-catch Kenner sulfonamide linker

Sulfonamide linkers

Sulfonamide linkers

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