193954-26-6Relevant articles and documents
A new GLP-1 analogue with prolonged glucose-lowering activity in vivo via backbone-based modification at the N-terminus
Bai, Xiaohui,Niu, Youhong,Zhu, Jingjing,Yang, An-Qi,Wu, Yan-Fen,Ye, Xin-Shan
, p. 1163 - 1170 (2016/03/01)
Glucagon-like peptide-1 (GLP-1) is an endogenous insulinotropic hormone with wonderful glucose-lowering activity. However, its clinical use in type II diabetes is limited due to its rapid degradation at the N-terminus by dipeptidyl peptidase IV (DPP-IV). Among the N-terminal modifications of GLP-1, backbone-based modification was rarely reported. Herein, we employed two backbone-based strategies to modify the N-terminus of tGLP-1. Firstly, the amide N-methylated analogues 2-6 were designed and synthesized to make a full screening of the N-terminal amide bonds, and the loss of GLP-1 receptor (GLP-1R) activation indicated the importance of amide H-bonds. Secondly, with retaining the N-terminal amide H-bonds, the β-peptide replacement strategy was used and analogues 7-13 were synthesized. By two rounds of screening, analogue 10 was identified. Analogue 10 greatly improved the DPP-IV resistance with maintaining good GLP-1R activation in vitro, and showed approximately a 4-fold prolonged blood glucose-lowering activity in vivo in comparison with tGLP-1. This modification strategy will benefit the development of GLP-1-based anti-diabetic drugs.
Convenient and simple synthesis of N-{[(9H-fluoren-9- yl)methoxy]carbonyl}-(Fmoc) protected β-amino acids (=homo-α-amino acids) employing Fmoc-α-amino acids and dicyclohexylcarbodiimide(DCC) mixtures
Ananda,Suresh Babu
, p. 418 - 423 (2007/10/03)
A simple approach for the homologation of α-amino acids to β-amino acids by the Arndt-Eistert method employing Fmoc-α-amino acid and N, N1- dicyclohexylcarbodiimide (DCC) mixture for the acylation of diazomethane, synthesizing the key intermediates Fmoc-α-amino acyldiazomethanes as crystalline solids is described.
Preparation of N-Fmoc-Protected β2- and β3-Amino Acids and Their Use as Building Blocks for the Solid-Phase Synthesis of β-Peptides
Guichard, Gilles,Abele, Stefan,Seebach, Dieter
, p. 187 - 206 (2007/10/03)
N-Fmoc-Protected (Fmoc = (9H-fluoren-9-ylmethoxy)carbonyl) β-amino acids are required for an efficient synthesis of β-oligopeptides on solid support. Enantiomerically pure Fmoc-β3-amino acids (β3: side chain and NH2 at C(3)(=C(β))) were prepared from Fmoc-protected (S)- and (R)-α-amino acids with aliphatic, aromatic, and functionalized side chains, using the standard or an optimized Arndt-Eistert reaction sequence. Fmoc-β2-Amino acids (β2 side chain at C(2), NH2 at C(3)(=C(β))) configuration bearing the side chain of Ala, Val, Leu, and Phe were synthesized via the Evans' chiral auxiliary methodology. The target β3-heptapeptides 5-8, a β3- pentadecapeptide 9 and a β2-heptapeptide 10 were synthesized on a manual solid-phase synthesis apparatus using conventional solid-phase peptide synthesis procedures (Scheme 3). In the case of β3-peptides, two methods were used to anchor the first β-amino acid: esterification of the ortho-chlorotrityl chloride resin with the first Fmoc-β-amino acid 2 (Method I, Scheme 2) or acylation of the 4-(benzyloxy)benzyl alcohol resin (Wang resin) with the ketene intermediates from the Wolff rearrangement of amino-acid-derived diazo ketone 1 (Method II, Scheme 2). The former technique provided better results, as exemplified by the synthesis of the heptapeptides 5 and 6 (Table 2). The intermediate from the Wolff rearrangement of diazo ketones 1 was also used for sequential peptide-bond formation on solid support (synthesis of the tetrapeptides 11 and 12). The CD spectra of the β2- and β3-peptides 5, 9. and 10 show the typical pattern previously assigned to an (M) 31 helical secondary structure (Fig.). The most intense CD absorption was observed with the pentadecapeptide 9 (strong broad negative Cotton effect at ca. 213 nm); compared to the analogous heptapeptide 5, this corresponds to a 2.5 fold increase in the molar ellipticity per residue!
