N-DICHLOROACETYL DERIVATIVES OF SERINE AND THREONINE AND OF THEIR ESTERS AND SODIUM SALTS

1960 ◽  
Vol 38 (7) ◽  
pp. 1135-1140 ◽  
Author(s):  
I. Levi ◽  
A. E. Koller ◽  
G. Laflamme ◽  
J. W. R. Weed

The N-dichloroacetyl derivatives of DL-serine and DL-threonine were prepared by the Schotten–Baumann reaction from the amino acids and dichloroacetyl chloride. Negative ninhydrin tests coupled with elementary analyses indicated that only the amino group was acylated. The ester derivatives of these compounds were prepared either by esterification of the N-dichloroacetyl-DL-amino acid with diazomethane or by the reaction of the amino acid ester with dichloroacetyl chloride in the presence of triethylamine. The sodium salts and the esters were tested for antitumor activity against sarcoma 37 in mice and Walker carcinoma 256 in rats. In both cases regression of the tumors was obtained.


2021 ◽  
Vol 22 (12) ◽  
pp. 6252
Author(s):  
Paula Ossowicz-Rupniewska ◽  
Rafał Rakoczy ◽  
Anna Nowak ◽  
Maciej Konopacki ◽  
Joanna Klebeko ◽  
...  

The potential of bacterial cellulose as a carrier for the transport of ibuprofen (a typical example of non-steroidal anti-inflammatory drugs) through the skin was investigated. Ibuprofen and its amino acid ester salts-loaded BC membranes were prepared through a simple methodology and characterized in terms of structure and morphology. Two salts of amino acid isopropyl esters were used in the research, namely L-valine isopropyl ester ibuprofenate ([ValOiPr][IBU]) and L-leucine isopropyl ester ibuprofenate ([LeuOiPr][IBU]). [LeuOiPr][IBU] is a new compound; therefore, it has been fully characterized and its identity confirmed. For all membranes obtained the surface morphology, tensile mechanical properties, active compound dissolution assays, and permeation and skin accumulation studies of API (active pharmaceutical ingredient) were determined. The obtained membranes were very homogeneous. In vitro diffusion studies with Franz cells were conducted using pig epidermal membranes, and showed that the incorporation of ibuprofen in BC membranes provided lower permeation rates to those obtained with amino acids ester salts of ibuprofen. This release profile together with the ease of application and the simple preparation and assembly of the drug-loaded membranes indicates the enormous potentialities of using BC membranes for transdermal application of ibuprofen in the form of amino acid ester salts.



2012 ◽  
Vol 40 (1) ◽  
pp. 413-424 ◽  
Author(s):  
Li-Jun Li ◽  
Cheng Wang ◽  
Yu Qiao ◽  
Xiao-Yan Yang ◽  
Xing-Xing Hua ◽  
...  




1960 ◽  
Vol 1 (2) ◽  
pp. 173-188 ◽  
Author(s):  
O. G. Fahmy ◽  
Myrtle J. Fahmy

The analysis of the variation in the mutation rate in the fractionated progeny of treated males, revealed a marked differential cell stage response to the various chemical series investigated. The mustard derivatives of amino-acids (particularly L-phenylalanine) exert their minimal mutagenicity on mature sperm, but possess an appreciable activity on other stages of spermatogenesis, including spermatogonia. The carboxylic-acid mustards produce their maximal effect on an early spermatid, but are practically ineffective on spermatocytes and spermatogonia. The amine mustard corresponding to the phenylalanine derivative is effective on the stages of spermiogenesis (including the early spermatids) as well as on the spermatocytes, but is inactive on the spermatogonia (at least the primary stages). The response of the gonia, therefore, is a function of the amino-acid moeity of the mutagen, and is not merely due to the presence of an amino-group in the molecule.



1968 ◽  
Vol 110 (2) ◽  
pp. 289-296 ◽  
Author(s):  
K. B. M. Reid ◽  
P T Grant ◽  
A. Youngson

1. S-Aminoethylcysteinyl derivatives of the A and B chains of cod insulin were prepared from the individual S-sulpho chains. 2. Studies on small peptides derived from the S-aminoethylated peptide chains by treatment with trypsin allowed the amino acid sequences in the region of the cysteinyl residues of the A and B peptide chains to be defined. 3. The six amide groups in cod insulin were located by complete digestion of small peptides from the A and B chains with aminopeptidase followed by amino acid analyses. 4. The results, together with previous studies on the oxidized A and B chains, define the sequences of the 51 amino acids that constitute cod insulin.



1975 ◽  
Vol 53 (9) ◽  
pp. 1005-1009 ◽  
Author(s):  
C. S. Tsai ◽  
N. L. Fraser ◽  
H. Avdovich ◽  
J. P. Farant

Proton magnetic spectra of 3-phenyl-2-thiohydantoin derivatives of common amino acids in deuterated dimethyl sulfoxide were recorded. Spectral data pertaining to characteristic protons for diagnostic purpose were compiled. Their application to the N-terminal amino acid analysis of peptide by Edman degradation was examined.



1980 ◽  
Vol 23 (11) ◽  
pp. 1171-1174 ◽  
Author(s):  
R. Baurain ◽  
M. Masquelier ◽  
D. Deprez-De Campeneere ◽  
A. Trouet


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