Glycine ethyl ester acetylation

Compound 59 was prepared in six steps starting from iV-(/>-methoxybenzyl)glycine ethyl ester and (i )-O-acetyl-atrolactic chloride, as reported in Section 11.11.7.3. Stereoselective reduction of 59 with BH3 at the carbonyl in position 8 (the only ketone among the other carbonyls) gave compound 60 in high diastereomeric purity (>95%). This diol was further opened in basic conditions and lactonized (Scheme 5) to produce an omuralide analogue 61 which can be potentially selective for proteasome inhibition <20010L1395>. 

N-Acetyl-glycine ethyl ester 1.0x10"2 1.0 xlO2 0.008 8.0x10- ... 

Several later model systems were designed with the thought of separating products that are not enantiomers but diastereoisomers of each other. For instance in the coupling of acetyl-L-leucine to glycine ethyl ester racemization will yield acetyl-D-alloisoleucyl-glycine ethyl ester, because inversion at the a-carbon atom leads to a D-amino acid but chirality at the second chiral center, the -carbon atom is unaffected... 

Dextranases.—The L-lysyl e-amino-group and other amino-groups of a dextranase from Penicillium funiculosum have been acetylated the L-arginyl and L-cysteinyl residues reacted with cyclohexane-1,2-dione and 4-chloromercuribenzoic acid, respectively the L-histidyl residues have been modified by photo-oxidation and the carboxy-groups have been amidated with glycine ethyl ester. These modifications, which were carried out on separate batches of the enzyme, indicated that an L-cysteine residue outwith the active site is involved in activation of the enzyme by cobalt ions. 

Glycine, N- ((1,3-dihydro-l, 3-dioxo-2//-isomdol-2-yl)acetyl] -, ethyl ester (2641-02-3], 93... 

Selectivity studies with DTU indicated marked discrimination in the clathrate formation 23,45). As in other types of clathrates, the steric factor is important in differentiation between compounds of similar functionality but different shape. For example, DTU forms crystalline complexes with some alcohols (methanol, ethanol, propanol, 1-butanol) but not with others (2-butanol). It complexes the ethyl esters of N-acetyl derivatives of glycine, alanine, methionine and aspartic acid, but not of proline, serine, phenylalanine and glutamic acid. 

Acetic acid, />-Diii THyLAiaNOPHENYL>, ETHYL ESTER, 47, 69 Acetic anhydride, condensation with and acetylation of glycine, 46, 1 in cydization of o-foimylphenoxy-acetic add to coumarone, 46,26 in cydization of hippuric acid to... 

Glycine, 1054, 1056, 1059 acetylation, 1063 acid-base properties, 1057-1061 electrostatic potential map, 1053 ethyl ester, 1079, 1080 Glycogen, 995... 

Contrary to piracetam, a novel piracetam peptide analogue, ethyl ester of hf-phenyl-acetyl-L-prolyl-glycine (GSV-111 1 /xM) in isolated neurones of the snail Helix pomatia suppressed the high-threshold current independent of Ca (Ik(v)) by 49 18% (SOLNTSEVA etal. 1997). 

Benzyloxycarbonyl-glycyl-prolyl-leucine, 42B, 370 N-(Benzyloxycarbonyl)prolylleucine ethyl ester, 44B, 444 t-Amyloxycarbonyl-L-prolyl-L-prolyl-L-proline, 40B, 462 Cycloheptasarcosyl monohydrate, 41B, 556 N-Acetyl-bis(dehydrophenylalanine)-glycine, 4IB, 556 n, N-(Bromoacetyl)-L-phenylalanyl-L-phenylalanine ethyl 501... 

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