Novel glycolipids with thiourea- and urea-linkers have been synthesized as low-molecular-weight gelators by reacting glycosyl aminoacetamides with alkyl isothiocyanates and isocyanates. The influence of the linker groups on their self-assembly properties has been studied. A gelation study of the obtained neoglycolipids in various solvents showed that they are good hydrogelators. Urea-linked glycolipids showed better hydrogelating ability as compared to thiourea linked glycolipids. The influence of sugar head group and alkyl chain length on the glycolipid's self-assembly has also been studied. The fibrillar structures of the supramolecular hydrogels have been characterized by scanning electron microscopy (SEM). The thermal properties of the hydrogels formed by urea linked glycolipids have been studied by differential scanning calorimetry (DSC) and VT-NMR. Molecular packing has been studied by small angle (SAXS) and single crystal X-ray diffraction methods. © The Royal Society of Chemistry 2013.

Manoharan Mathiselvam

Duraikkannu Loganathan

Babu Varghese

Differential scanning calorimetry

Gelation

hydrogels

metabolism

Scanning electron microscopy

Self assembly

Thioureas

urea

X ray diffraction

Alkyl chain lengths

FIBRILLAR STRUCTURES

Isothiocyanates

LOW MOLECULAR WEIGHT

MOLECULAR PACKINGS

Single crystal X-ray diffraction method

SUPRAMOLECULAR HYDROGELS

Synthesis and characterizations

Lipids

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

RSC Advances

N-Linked glycosylation is not only present in eukaryotes but also occurs in archaea and bacteria and is mainly characterized by the β-glucosylamine linkage to the asparagine (GlcNAcβAsn). Earlier crystallographic studies aimed at understanding the structural significance of the linkage region constituents revealed that N-glycosidic torsion, φN is influenced considerably by variation in the glycan part as compared to the aglycon moiety. The φN value observed for XylβNHAc deviated maximum as compared to that of the model compound, GlcNAcβNHAc. The present work was undertaken to assess the influence of ribose on the N-glycosidic torsions and molecular assembly. Several ribopyranosyl alkanamides have been synthesized and crystal structures of three of them have been solved. A comprehensive crystal structure analysis of ribosyl alkanamides along with xylosyl and arabinosyl alkanamides showed the wide range of deviations in their φN values as compared to the negligible deviation shown by hexopyranosyl alkanamides. This study revealed the importance of C5-hydroxymethyl group and hydroxyl group configurations at C2, C3, and C4 stereocentres in controlling the N-glycosidic torsions. © 2013 Elsevier Ltd. All rights reserved.

Carbohydrate Research

Examination of the influence of C5-hydroxymethyl group and configurations of hydroxyl groups at C2, C3, and C4 stereocentres on the N-glycosidic torsion: Synthesis and X-ray crystallographic investigation of N-(d-ribopyranosyl) alkanamides as N-glycoprotein linkage region analogs

N-Glycoprotein linkage region constituents namely 2-deoxy-2-acetamido- β-d-glucopyranose (GlcNAc) and asparagine (Asn) are conserved among all eukaryotes. Earlier crystallographic studies on the linkage region conformation revealed that among all the models and analogs of the N-glycoprotein linkage region, XylβNHAc showed maximum deviation in the φN value as compared to the value reported for the model compound, GlcNAcβNHAc. In order to understand the effect of another pentopyranose, viz., arabinose, on the N-glycosidic torsion angles and molecular assembly, three arabinopyranosyl alkanamides were synthesized and their X-ray crystal structures elucidated. A comparative analysis of the N-glycosidic torsion, φN of the three analogs revealed the greater rotational freedom around the C1-N1 bond as compared to the GlcNAc derivatives. Molecular assembly of propionamido and chloroacetamido derivatives is characterized by the presence of anti-parallel bilayers of the molecules. This unique molecular assembly is hitherto unknown in all other models and analogs of N-glycoprotein linkage region. This study reveals that N-glycosidic torsions are influenced by the glycan as well as molecular packing. © 2013 Elsevier Ltd. All rights reserved.

Synthesis and X-ray crystallographic investigation of N-(α-d- arabinopyranosyl)alkanamides as N-glycoprotein linkage region analogs

The crystal structures of acetamido galactopyranosyl glucopyranose dihydrate was analyzed. The compound was synthesized by peracetylation of lactosylamine followed by lypophilization and treated with pyridine and acetic anhydride. The glucose and galactose residues were observed to adopt a 4C1 conformation. The hydrate molecule were observed to be involve in the network of hydrogen bonds. The N-acetyl group was found showed a Z-anti conformation.

Acta Crystallographica Section C: Crystal Structure Communications

β-1-acetamido-4-O-β-D-galactopyranosyl-D-glucopyranose dihydrate

América sin Nombre

10.14198/amesn2016.21

Visceral Medicine

Metabolic Syndrome in Children and Adolescents

IEEE Solid-State Circuits Magazine

The Early Days at UC Berkeley [Guest Editorial]

Chem. Commun.

Highly selective recognition of acetate and bicarbonate by thiourea-functionalised inverse opal hydrogel in aqueous solution

Synthesis and characterization of thiourea- and urea-linked glycolipids as low-molecular-weight hydrogelators

Journal	Data powered by TypesetRSC Advances
Publisher	Data powered by TypesetRoyal Society of Chemistry
ISSN	20462069
Open Access	No