TY - JOUR
T1 - 127. C-glycoside analogues of N4-(2-Acetamido-2-deoxy-β-D-glucopyranosyl)-L-asparagine
T2 - synthesis and conformational analysis of a cyclic C-glycopeptide
AU - Hoffmann, Matthias
AU - Burkhart, Fred
AU - Hessler, Gerhard
AU - Kessler, Horst
PY - 1996
Y1 - 1996
N2 - The synthesis of C-glycosidic analogues 15-22 of N4-(2-acetamido-2-deoxy-β-D-glucopyranosyl)-L-asparagine (ASn(N4GlcNAc)) possessing a reversed amide bond as an isosteric replacement of the N-glycosidic linkage is presented. The peptide cyclo(-D-Pro-Phe-Ala-CGaa-Phe-Phe-) (CGaa = C-glycosylated amino acid; 24) was prepared to demonstrate that 3-[(3-acetamido-2,6-anhydro-4,5,7-tri-O-benzyl-3-deoxy-β-D-glycero-D- guloheptonoyl)amino]-2-[(9H-fluoren-9-yloxycarbonyl)amino]propanoic acid (22) can be used in solid-phase peptide synthesis. The conformation of 24 was determined by NMR and molecular-dynamics (MD) techniques. Evidence is provided that the CGaa side chain interacts with the peptide backbone. The different C-glycosylated amino acids 15-21 were prepared by coupling 3-acetamido-2,6-anhydro-4,5,7-tri-O-benzyl-3-deoxy-β-D-glycero-D-gulo- heptonic acid (4) with diamino-acid derivatives 8-14 in 83-96% yield. The synthesis of 4 was performed from 2-(acetamido-3,4,6-tri-O-benzyl-2-deoxy-β-D-glucopyranosyl)tributylstannane (2) by treatment with BuLi and CO2 in 83% yield. Similarly, propyl isocyanat yielded the glycoheptonamide 7 in 52% from 2. Compound 2 was obtained from 2-acetamido-3,4,6-tri-O-benzyl-2-deoxy-D-glucopyranose (1) by chlorination and addition of tributyltinlithium in 74% yield. A procedure for a multigram-scale synthesis of 1 is given.
AB - The synthesis of C-glycosidic analogues 15-22 of N4-(2-acetamido-2-deoxy-β-D-glucopyranosyl)-L-asparagine (ASn(N4GlcNAc)) possessing a reversed amide bond as an isosteric replacement of the N-glycosidic linkage is presented. The peptide cyclo(-D-Pro-Phe-Ala-CGaa-Phe-Phe-) (CGaa = C-glycosylated amino acid; 24) was prepared to demonstrate that 3-[(3-acetamido-2,6-anhydro-4,5,7-tri-O-benzyl-3-deoxy-β-D-glycero-D- guloheptonoyl)amino]-2-[(9H-fluoren-9-yloxycarbonyl)amino]propanoic acid (22) can be used in solid-phase peptide synthesis. The conformation of 24 was determined by NMR and molecular-dynamics (MD) techniques. Evidence is provided that the CGaa side chain interacts with the peptide backbone. The different C-glycosylated amino acids 15-21 were prepared by coupling 3-acetamido-2,6-anhydro-4,5,7-tri-O-benzyl-3-deoxy-β-D-glycero-D-gulo- heptonic acid (4) with diamino-acid derivatives 8-14 in 83-96% yield. The synthesis of 4 was performed from 2-(acetamido-3,4,6-tri-O-benzyl-2-deoxy-β-D-glucopyranosyl)tributylstannane (2) by treatment with BuLi and CO2 in 83% yield. Similarly, propyl isocyanat yielded the glycoheptonamide 7 in 52% from 2. Compound 2 was obtained from 2-acetamido-3,4,6-tri-O-benzyl-2-deoxy-D-glucopyranose (1) by chlorination and addition of tributyltinlithium in 74% yield. A procedure for a multigram-scale synthesis of 1 is given.
UR - http://www.scopus.com/inward/record.url?scp=0029838551&partnerID=8YFLogxK
U2 - 10.1002/hlca.19960790602
DO - 10.1002/hlca.19960790602
M3 - Article
AN - SCOPUS:0029838551
SN - 0018-019X
VL - 79
SP - 1519
EP - 1532
JO - Helvetica Chimica Acta
JF - Helvetica Chimica Acta
IS - 6
ER -