Of muramic acid

FIGURE 7.15 Structures of muramic acid aud ueuramiuic acid aud several depictions of sialic acid. 

In muramic acid, the 2-hydroxyl group of D-glucose is replaced by an amine group, and a lactic acid group is attached to OH-3. The structure of muramic acid [2-amino-3-0-(D-l-carboxyethyl)-2-deoxy-D-glucopyranose] is given in formula 12. 

A. Fox and R. M. T. Rosario, Quantification of muramic acid, a marker for bacterial peptidoglycan in dust collected from hospital and home air-conditioning filters using gas-chromatography mass spectrometry. Indoor Air-Intemat. J. Air Quality Cl. 4 239 (1994). 

Fox, A. Fox, K. Christensson, B. Harrelson, D. Krahmer, M. Absolute identification of muramic acid at trace levels in human septic fluids in vivo and absence in aseptic fluids. Infect. Immun. 1996, 64, 3911-3955. 

Fox, A. Wright, L. Fox, K. Gas chromatography-tandem mass spectrometry for trace detection of muramic acid, a peptidoglycan marker in organic dust. I. Microbiol. Meth. 1995, 22,11-26. 

Mielniczuk, Z., Mielniczuk, E., and Larsson, L. (1995), Determination of muramic acid in organic dust by gas chromatography-mass spectrometry, J. Chromatogr. B, 670, 167-172. 

Kozar, M., and Fox, A. (2002), Analysis of a stable halogenated derivative of muramic acid by gas chromatography-negative ion chemical ionization tandem mass spectrometry, J. Chromatogr., 946, 229-238. 

Sebastian, A., Harley, W., Fox, A., and Larsson, L. (2004), Evaluation of the methyl ester O-methyl acetate derivative of muramic acid for the determination of peptidoglycan in environmental samples by ion-trap GC-MS-MS,/. Environ. Monit., 6,1-6. 

Anion of muramic acid, O-Lactyl-GlcNAc (Mur), found in bacterial cell wall polysaccharides. 

Gram-positive organisms Mainly a mixed polymer of muramic acid and peptide techoic acids and polysaccharide... 

The lactyl carboxyl group was unmasked by exposure of the phenylsulfonylethyl ester to DBU. Carboxyl group activation of muramic acid derivative 21 was achieved by conversion to the corresponding NHS ester (N-hydroxysuccinimide, EDCI, DMF). The pentapeptide fragment 10 was readily prepared in quantity using standard peptide synthesis protocols [Scheme 7]. Addition of a DMF solution of pentapeptide 10 to a solution of PrNEt2 and the NHS ester deriving from 21 provided the protected muramyl pentapeptide 9 in excellent overall yield. 

Zhang, X., and Amelung, W. (1996). Gas chromatographic determination of muramic acid, glucosamine, galactosamine and mannosamine in soils. Soil Biol. Biochem. 28, 1201-1206. 

Whiton, R. S., Lau, P., Morgan, S. L., Gilbart, J., and Fox, A. (1985). Modifications in the alditol acetate method for analysis of muramic acid and other neutral and amino sugars by capillary gas chromatography-mass spectrometry with selected ion monitoring. /. Chromatogr. A 347, 109—120. 

Another application of alkoxylation of nitro-olefins is in the synthesis of positional isomers of muramic acid.156 Addition of isopropyl L-lactate or isopropyl D-lactate to 141 led to the side-chain epimers 199 and 200, respectively, in yields of over 80%. When isopropyl dl-lactate was used, 199 and 200 were obtained as a mixture in which, interestingly, the former preponderated. Removal of protecting groups, reduction, and derivation furnished various derivatives of 3-amino-2-0-[D(and L)-l-carboxyethyl]-3-deoxy-D-glucose (201). 

Penicillins inhibit the cross-linking of muramic acid in the bacterial cell wall. This results in a lack of structural integrity and eventual cell lysis. 

Figure 2.15 The Synthesis of Muramic Acid and Sialic Acid (A), and KDO (B)...

A 1-thiolacetate derivative of muramic acid has been converted... 

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