Asparagine derivatives

A similar synthesis starting from the derivatives of maltose (55), lactose (46), and cellobiose (57) to give the L-asparagine derivatives 56,48, and 58, respectively, was accomplished by Dunstan and Hough.46... 

In order to construct the L-asparagine derivative of per-O-acetylated 0-(2-acetamido-2-deoxy-/ -D-glucopyranosyl( 1 — 4)-2-acetamido-2-deoxy-D-glucose (7), Spinola and Jeanloz (13) used (the sensitive) silver azide for conversion of the a-chloro anomer of the chitobiose derivative 8 into the / -azido derivative 9. Kunz and associates (14,15) have accomplished the conversion of the a-chloro anomer of 8 into 9 using sodium azide in the presence of tri-n-octyl-methylammonium chloride as a phase-transfer catalyst in chloroform water. 

Similarly Thiem and Wiemann (92) conducted the galactosylation of the 2-acetamido-2-deoxy-D-glucose-L-asparagine derivative 183 and the chitobiose-L-asparagine derivative 187 to furnish the di- and trisaccharide derivatives 185 and 188, respectively, by using galactosyltransferase. 

The building-block approach, where a glycosyl asparagine derivative is used in stepwise assembly of the glycopeptide [34,146-151]. 

Zurabyan, S E, Macharadze, R G, Khorlin, A Y, Synthesis of 2-acetamido-2-deoxy-(i-D-glucopyranosyl-L-asparagine derivative, Bioorg. Khim., 4, 1135-1136, 1978. 

KHORLIN, Y.A., ZYRABYAN, E., MACHARADZE, R., Synthesis of glyco-sylamides and 4-N-glycosyl-L-asparagine derivatives, Carbohydr. Res. 85 (1980) 201-208. 

Aspartic acid derivative, asparagine derivative, His-His cross-links... 

Conversion of stereospecifically labeled samples of aspartic acid 21a to the corresponding asparagine derivatives 241 has been achieved by ourselves (224) and others (225). The enzyme -methylaspartase has been used to prepare (2S, 3S)-[3- Hi]-3-methylaspartate and (2S, 3S)-[3- Hi]-3-ethylaspartate (222, 226, 227). 

T. Inazu and K. Kobayashi, A new simple method for the synthesis of W -Fmoc-A -glyco-sylated-L-asparagine derivatives, Synlett (1993) 869-870. 

Three major amide substituted asparagine derivatives have been isolated from various species of the Cucurbitaceae (Frisch et ai, 1967). The com-... 

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