Fragment couplings, synthesis

Solid Phase Fragment Coupling Synthesis of Hirudin... 

Scheme 14.1 Fragment coupling synthesis of azacalix[2]arene[2]triazines [14]...

Scheme 14.5 Fragment coupling synthesis of azacalix[n]pyridines (n = 4—10) [21-23]...

Scheme 14.6 [3 + 3] Fragment coupling synthesis of azacalix[6]aromatics [28]...

Schemes Fragment-coupling synthesis of azacalixpyridines and azacalixarenepyrid-ines [24-26]...

Schemes Fragment-coupling synthesis of azacalixarenes with NH bridges. Numbers in parentheses indicate the reaction yields in the fragment-coupling syntheses using monomers 30 and 32, or 31 and 32 as substrates. Those in square brackets represent the yields in the reaction of 33 and 34 [30]...

Scheme 10 Fragment-coupling synthesis of regioselectively N-methylated azacalix[8]arene 38f [31]...

Schellenberger, V., Schellenberger, U., Jakubke, H.-D., Hansicke, A., Bienert, M., Krause, E. (1990). Chymotrypsin-catalyzed fragment coupling synthesis of D-Phe(6)-GnRH. 

JC Hendrix, JT Jarrett, ST Anisfield, PT Lansbury. Studies related to a convergent fragment-coupling approach to peptide synthesis using the Kaiser oxime resin. J Org Chem 57, 3414, 1992. 

J Heibl et al. Large-scale synthesis of hematoregulatory nonapeptide SK F 1077647 by fragment coupling. J Pept Res 54, 54, 1999. 

The iodoetherification strategy was applied to the synthesis of the smaller fragment coupling component 109 as well (Scheme 16). Silylation of alcohol 104 [30] (76% de) allowed the separation of the pure desired diastereomer, which in turn was subjected to hydroboration/oxidation, sulfide formation with thiol 105, and oxidation to give sulfone 106. The requisite y-triethylsilyloxy alkene functionality in 107 was constructed as a diastereomeric E) Z)=l.2 l mixture by another sulfone-based olefination of aldehyde 90 with 106. Treatment of 106 with... 

A relatively small number of (A-hydroxyamide) peptides have been prepared using the step-by-step or the fragment coupling strategy in solution,l45 4648-50 or the solid-phase synthesis approach. 51 The (A-hydroxyamide) tetrapeptide H-D,L-(BzlO)Ala-Glyt t[CO-N(OBzl)]D,L-Ala-Gly-NHPh 41 has been prepared by a step-by-step procedure, 45 which has been extended to the synthesis of the terminally blocked (A-hydroxyamide) hexapeptide Aci >[CO-N(OH)]Ala- Glyi >[CO-N(OH)]Ala 2-Gly-NHPh 42 having alternate A-hydroxyamide/ amide links (Scheme 13). 461... 

The Ugi reaction can be used in peptide synthesis following two different routes (1) formation of an a-amino acid bridge and (2) promotion of peptide fragment coupling. Route (1) requires the use of a cleavable amine whereas route (2) requires the use of a cleavable aldehyde (Scheme 2.19). 

Romo D, Meyer SD et al (2002) Total synthesis of (—)-rapamycin using an Evans-Tish-chenko fragment coupling. J Am Chem Soc 115 7906-7907... 

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