LacNAc

R. Wischnat, R. Martin, C.-H. Wong, Synthesis of a New Class of N-Linked Lewis and LacNAc Analogues as Potential Inhibitors of Human Fucosyltransferases A General Method for the Incorporation of an Iminocyclitol as a Transition-State Mimetic of the Donor Sugar to the Acceptor , J. Org. Chem 1997, 63, 8361-8365. 

VAAVTEKLRAGT mosquito midgut glycoproteins contains Man-o -(l-6)- and LacNAc components ... 

Scheme 5.6 Poly-LacNAc-derived oligosaccharides synthesized by combinatorial biocatalysis [80].

N. meningitides and human ST6Gal-I, EC2.4.99.1) were exploited to add sialic acid in a2-3 and a2-6 linkages to the terminal galactose residue of mono-, di- and tri-LacNAc. The fusion of the bacterial ST3 with CMP-Neu5Ac synthetase [83] generated the donor substrate in situ from added NeuSAc and CTP. 

By carefully adjusting the distances between two sialoside residues in a number of divalent clusters. Click and Knowles [105] have obtained dimer 104 having the two sialic acid 5.7 nm apart. Compound 104 was 100-fold more potent than methyl a-sialoside (Neu5Aca2Me) in influenza virus inhibitions and 500-fold more potent in the case of polyomia virus. Alternatively, sialyl-a-(2,6)-/3-LacNAc dimers (105) branched at different positions of synthetic peptides, including compact glycine-rich and helical proline-rich peptides, afforded clusters which were only 8- and 4-fold more potent, respectively, than the corresponding monovalent trisaccharide [106]. 

Biotinylated sialyl LacNAc with PAA backbone (Sialyl Lac-NAc Neu5Aca2-3Gaipi-4GlcNAc(3- PAA-biotin, Glycotech). 

Fig. 1. An analysis procedure of a ptiotocrosslinked sugar an ay by SPR imaging. A fabricated sugar array with sialyl T, sialyl Tn and sialyl LacNAc were exposed with MAFI, regenerated with NaOFI and then, exposed with SA and anti-SA.

Fig. 2. The interaction anaiysis of the photocrossiinked sugar array by SPR imaging, (a) SPR signai changes on siaiyi T, siaiyi Tn, siaiyi LacNAc and biank spots, (b) SPR difference images by exposures of WlAH and anti-SA.

H = OH, lactose R = NHAc, LacNAc Lac-DPPA LacNAc-DPPA... 

Chemoenzymatic solution- and solid-phase synthesis of O-glycopeptides of the mucin domain of MAdCAM-1. A general route to O-LacNAc, O-sialyl-LacNAc, and O-sialyl-Lewis-X peptides, J. Am. Chem. Soc., 119 (1997) 8766-8776. 

Fig. 2. iV-glycans of the hybrid type. A triantennary structure with sialylated Af-acetyllactosamine (LacNAc) building blocks B biantennary structure with sialylated or fucosylated poly-LacNAc building blocks. The N-glycan core structure is written in bold letters... 

Fig. 3. O-glycans of the mucin type. A core 2 structure with poly-LacNAc and blood group epitope A B core 4 structure with sialyl Lex epitope. The core structures are written in bold letters...

Fig. 9. Synthesis of /V-acetyllactosamin (LacNAc, 7) with pl-4 galactosidase. The thermodynamic approach (reverse hydrolysis) involves D-galactose (5) as donor and /V-acctyl-D-glucosanminc (6) as acceptor substrate. Activated galactosyl donors (8-10) are used in the kinetic approach (trans-glycosylation)...

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