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Acylamino acids

Azlactones (anhydrides of a-acylamino acids) are formed by the condensation of aromatic aldehydes with acyl derivatives of glycine in the presence of acetic anhydride and anhydrous sodium acetate. Thus beiizaldehyde and acetyl-... [Pg.907]

Alkylethers (269), R2 = alkyl, are obtained by the action of phosphorus pentasulfide on alkyl esters of a-acylamino acids (64, 334, 711) by means of the GabriePs synthesis (Section II.4), while aryl ethers (269), = aryl,... [Pg.304]

Enzymatic hydrolysis of A/-acylamino acids by amino acylase and amino acid esters by Hpase or carboxy esterase (70) is one kind of kinetic resolution. Kinetic resolution is found in chemical synthesis such as by epoxidation of racemic allyl alcohol and asymmetric hydrogenation (71). New routes for amino acid manufacturing are anticipated. [Pg.279]

D-amino acids DL-acylamino acids D-amino acylase 206... [Pg.292]

Stannyl esters have been prepared to protect a -COOH group in the presence of an -NH2 group [( -Bu3Sn)20 or -Bu3SnOH, CgH, reflux, 88%]. Stannyl esters of A -acylamino acids are stable to reaction with anhydrous amines and to water and alcohols aqueous amines convert them to ammonium salts. Stannyl esters of amino acids are cleaved in quantitative yield by water or alcohols (PhSK, DMF, 25°, 15 min, 63% yield or HOAc, EtOH, 25°, 30 min, 77% yield). ... [Pg.442]

The azlactones of a-benzoylaminocinnamic acids have traditionally been prepared by the action of hippuric acid (1, Ri = Ph) and acetic anhydride upon aromatic aldehydes, usually in the presence of sodium acetate. The formation of the oxazolone (2) in Erlenmeyer-Plochl synthesis is supported by good evidence. The method is a way to important intermediate products used in the synthesis of a-amino acids, peptides and related compounds. The aldol condensation reaction of azlactones (2) with carbonyl compounds is often followed by hydrolysis to provide unsaturated a-acylamino acid (4). Reduction yields the corresponding amino acid (6), while drastic hydrolysis gives the a-0X0 acid (5). ... [Pg.229]

Cryoscopic studies have shown that a-acylamino acids undergo... [Pg.94]

Belleau and Malek47 introduced the use of this reagent (EEDQ) to couple acylamino acids with amino acid esters, and Dunstan and Hough46 were able to couple the peracetates of maltosyl-, lactosyl-, and cello-biosyl-amine (55, 47, and 57, respectively) with 1-benzyl N-(benzyl-... [Pg.144]

The pH-sensitive liposomes consist of mixtures of several saturated egg phosphatidylcholines and several A -acylamino acids. The release of drug is suggested to be a function of acid-base equilibrium effected by the interaction between ionizable amino acids and N-acy-lamino acid headgroups of the liposomes. There appears to be a close relation between Tc and pH effect [72],... [Pg.556]

Amides of Amino Acids Involving the Amino Group (7V-Acylamino Acids)... [Pg.109]

Peptide-bond formation between an A -alkoxycarbonylamino acid and an amino-containing component usually proceeds in the same way as described for coupling an Y-acylamino acid or peptide (see Section 1.9), except for the side reaction (Figure 1.7, path B) of oxazolone formation. Aminolysis of the activated component (Figure 1.10, path A) gives the desired peptide. There are three aspects of the side reaction... [Pg.10]

CARBODIIMIDE-MEDIATED REACTIONS OF N-ACYLAMINO ACIDS AND PEPTIDES... [Pg.13]

FIGURE 1.14 Carbodiimide-mediated reactions of At-acylamino acids and peptides. [Pg.14]

FMF Chen, NL Benoiton. Do acylamino acid and peptide anhydrides exist in K Blaha, P Malon, eds. Peptides 1982. Proceedings of the 17th European Peptide Symposium. Walter de Gruyter, Berlin, 1983, pp 67-70. [Pg.14]

FMF Chen, M Slebioda, NL Benoiton. Mixed carboxylic-carbonic acid anhydrides of acylamino acids and peptides as a convenient source of 2,4-dialky 1 -5(AH)-oxazo-lones. Int J Pept Prot Res 31, 339, 1988. [Pg.57]

NL Benoiton, YC Lee, FMF Chen. Studies on asymmetric induction associated with the coupling of JV-acylamino acids and JV-benzyloxycarbonyldipeptides. Int J Pept ProtRes 38, 574, 1991. [Pg.101]

W Williams, GT Young. Amino acids and peptides. XXXV. Effect of solvent on the rates of racemization and coupling of acylamino acid p-nitrophenyl esters. Base strengths of amines in organic solvents, and related investigations. J Chem Soc Perkin Trans 1 1194, 1972. [Pg.108]

Scheme 1 a Amidocarbonylation of aldehydes b Applications of N-acylamino acids... [Pg.214]

The two-step activation of oxazolidinones is depicted in Fig. 8.26. Hydrolysis yields an A-(l -hydroxy alkyl) derivative, which breaks down to liberate the peptide or A-acylamino acid (Fig. 8.26, Reactions a and b). Since oxazolidinones are prepared by the condensation of a peptide and an aldehyde (Fig. 8.26, Reaction c), the reverse reaction (i. e., one-step activation) cannot be excluded. Examples of this type of prodrug are provided by a series of oxazolidinones of the general structure 8.190 (R = PhCH20 R = H, Me, i-Pr, or PhCH2 R" = H, Me, or Ph Fig. 8.26) [248]. In phosphate buf-... [Pg.533]

Similarly, acylamino acids can be prepared with 100% atom utilization via palladium-catalyzed amidocarbonylation. " The method was used for the synthesis of a surfactant from sarcosine (Figure 9.8). [Pg.196]


See other pages where Acylamino acids is mentioned: [Pg.293]    [Pg.270]    [Pg.781]    [Pg.109]    [Pg.333]    [Pg.261]    [Pg.340]    [Pg.124]    [Pg.13]    [Pg.16]    [Pg.42]    [Pg.56]    [Pg.97]    [Pg.109]    [Pg.199]    [Pg.203]    [Pg.216]    [Pg.218]    [Pg.220]    [Pg.220]   
See also in sourсe #XX -- [ Pg.613 ]




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1- Acylamino

A -acylamino acids/esters

A-acylamino acids

Active acylamino)acrylic acid

Acylamino acid racemase

Acylamino acids racemization

Acylamino acids, azlactonization

Acylamino acids, preparation

Acylamino acrylic acids

Carbodiimide-Mediated Reactions of A-Acylamino Acids and Peptides

Hydrolysis of N-acylamino Acids

IV-Acylamino acids

N-Acylamino acids

N-acylamino acid ester

N-acylamino acid racemase

O-Acylamino acid

Reactions of the amide group in acylamino acids and peptides

V-Acylamino acids

With Ammonia (on o-Acylamino Acids)

With Ammonia or Amines (on o-Acylamino Acids)

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