Carmen Jimenez Castells - Academia.edu (original) (raw)

Papers by Carmen Jimenez Castells

Research paper thumbnail of Optimized synthesis of aminooxy-peptides as glycoprobe precursors for surface-based sugar–protein interaction studies

Bioorganic & Medicinal Chemistry Letters, 2007

An improved procedure for solid phase coupling of Boc-aminooxyacetic acid to peptides is describe... more An improved procedure for solid phase coupling of Boc-aminooxyacetic acid to peptides is described. By avoiding basecontaining activation mixtures which cause over-acylation, it practically suppresses this unwanted side reaction and leads to near quantitative yields of Aoa-peptides, useful as glycoprobe precursors in glycomic studies.

Research paper thumbnail of Synthesis and biological properties of β-turned Aβ 31–35 constrained analogues

Bioorganic & Medicinal Chemistry Letters, 2008

A series of constrained pentapeptide analogues of the fragment Ab 31-35 has been prepared using s... more A series of constrained pentapeptide analogues of the fragment Ab 31-35 has been prepared using solid phase synthesis protocols. The results of conformational studies and surface plasmon resonance (SPR) experiments seem to indicate that the affinity of these constrained analogues for immobilized Ab 25-35 peptide could be related to their ability to adopt a Leu34N-Ile31O b-turnlike folded conformation.

Research paper thumbnail of Neo-glycopeptides: the importance of sugar core conformation in oxime-linked glycoprobes for interaction studies

Glycoconjugate Journal, 2008

Carbohydrate binding proteins, such as lectins, are crucial in numerous biological recognition pr... more Carbohydrate binding proteins, such as lectins, are crucial in numerous biological recognition processes. While binding may be mediated by a single monosaccharide, several lectins have shown exquisite epimer and linkage recognition indicating that a larger structure is essential for optimal interaction. Several approaches have been described for their detailed study, including lectinosorbent assays, microarrays and surface plasmon resonance (SPR). Most of these approaches ignore that the aglycon-bound monosaccharide is often in a non-natural conformation that affects the occurring binding event. In this paper we demonstrate that oxime-bound glycans, employed in such approaches, occur predominantly in the open form (~70%). Through the use of a secondary amine, the aglycon-bound monosaccharide in the resulting neo-glycopeptide probe is forced into the ring-form. Resulting structures were analyzed by means of nuclear magnetic resonance and differential derivatization experiments. The impact of ring closure was further demonstrated through interaction studies using SPR and various lectins with distinct binding specificities.

Research paper thumbnail of Recent progress in the field of neoglycoconjugate chemistry

Biomolecular Concepts, 2010

Glycosylation is probably the most complex secondary gene event that affects the vast majority of... more Glycosylation is probably the most complex secondary gene event that affects the vast majority of proteins in nature resulting in the occurrence of a heterogeneous mixture of glycoforms for a single protein. Many functions are exerted by single monosaccharides, well-defined oligosaccharides, or larger glycans present in these glycoproteins. To unravel these functions it is of the utmost importance to prepare welldefined single glycans conjugated to the underlying aglycon. In this review, the most recent developments are described to address the preparation of carbohydrate-amino acid (glycoconjugates). Naturally occurring N-and O-linked glycosylation are described and the preparation of non-natural sugar-amino acid linkages are also included.

Research paper thumbnail of Optimized synthesis of aminooxy-peptides as glycoprobe precursors for surface-based sugar–protein interaction studies

Bioorganic & Medicinal Chemistry Letters, 2007

An improved procedure for solid phase coupling of Boc-aminooxyacetic acid to peptides is describe... more An improved procedure for solid phase coupling of Boc-aminooxyacetic acid to peptides is described. By avoiding basecontaining activation mixtures which cause over-acylation, it practically suppresses this unwanted side reaction and leads to near quantitative yields of Aoa-peptides, useful as glycoprobe precursors in glycomic studies.

Research paper thumbnail of Synthesis and biological properties of β-turned Aβ 31–35 constrained analogues

Bioorganic & Medicinal Chemistry Letters, 2008

A series of constrained pentapeptide analogues of the fragment Ab 31-35 has been prepared using s... more A series of constrained pentapeptide analogues of the fragment Ab 31-35 has been prepared using solid phase synthesis protocols. The results of conformational studies and surface plasmon resonance (SPR) experiments seem to indicate that the affinity of these constrained analogues for immobilized Ab 25-35 peptide could be related to their ability to adopt a Leu34N-Ile31O b-turnlike folded conformation.

Research paper thumbnail of Neo-glycopeptides: the importance of sugar core conformation in oxime-linked glycoprobes for interaction studies

Glycoconjugate Journal, 2008

Carbohydrate binding proteins, such as lectins, are crucial in numerous biological recognition pr... more Carbohydrate binding proteins, such as lectins, are crucial in numerous biological recognition processes. While binding may be mediated by a single monosaccharide, several lectins have shown exquisite epimer and linkage recognition indicating that a larger structure is essential for optimal interaction. Several approaches have been described for their detailed study, including lectinosorbent assays, microarrays and surface plasmon resonance (SPR). Most of these approaches ignore that the aglycon-bound monosaccharide is often in a non-natural conformation that affects the occurring binding event. In this paper we demonstrate that oxime-bound glycans, employed in such approaches, occur predominantly in the open form (~70%). Through the use of a secondary amine, the aglycon-bound monosaccharide in the resulting neo-glycopeptide probe is forced into the ring-form. Resulting structures were analyzed by means of nuclear magnetic resonance and differential derivatization experiments. The impact of ring closure was further demonstrated through interaction studies using SPR and various lectins with distinct binding specificities.

Research paper thumbnail of Recent progress in the field of neoglycoconjugate chemistry

Biomolecular Concepts, 2010

Glycosylation is probably the most complex secondary gene event that affects the vast majority of... more Glycosylation is probably the most complex secondary gene event that affects the vast majority of proteins in nature resulting in the occurrence of a heterogeneous mixture of glycoforms for a single protein. Many functions are exerted by single monosaccharides, well-defined oligosaccharides, or larger glycans present in these glycoproteins. To unravel these functions it is of the utmost importance to prepare welldefined single glycans conjugated to the underlying aglycon. In this review, the most recent developments are described to address the preparation of carbohydrate-amino acid (glycoconjugates). Naturally occurring N-and O-linked glycosylation are described and the preparation of non-natural sugar-amino acid linkages are also included.