cas 52-89-1, L-Cysteine hydrochloride anhydrous

Articles about 52-89-1Total 8 be found

Cycloforskamide, a cytotoxic macrocyclic peptide from the sea slug Pleurobranchus forskalii
A macrocylic dodecapeptide, cycloforskamide, was isolated from the sea slug Pleurobranchus forskalii, collected off Ishigaki Island, Japan. Its planar structure was deduced by extensive NMR analyses and was further confirmed by MS/MS fragmentation analyses. Finally, the absolute configuration was determined by total hydrolysis and chiral-phase gas chromatographic analysis. This novel dodecapeptide contains three d-amino acids and three thiazoline heterocycles and exhibits cytotoxicity against murine leukemia P388 cells, with an IC 50 of 5.8 μM.
Tan, Karen Co,Wakimoto, Toshiyuki,Takada, Kentaro,Ohtsuki, Takashi,Uchiyama, Nahoko,Goda, Yukihiro,Abe, Ikuro
p. 1388 - 1391
(2013/08/23)

THIOL-CONTAINING COMPOUNDS FOR THE REMOVAL OF ELEMENTS FROM CONTAMINATED MILIEU AND METHODS OF USE
Sulfur-containing ligands and methods of their utilization for binding metals and/or main group elements and removing them from fluids, solids, gases and/or tissues are disclosed. The ligands are of the general structure: where R1 comprises benzene, pyridine, pyridin-4-one, naphthalene, anthracene, phenanthrene or alkyl groups, R2 comprises hydrogen, alkyls, aryls, a carboxyl group, carboxylate esters, organic groups or biological groups, R3 comprises alkyls, aryls, a carboxyl group, carboxylate esters, organic groups or biological groups, X comprises hydrogen, lithium, sodium, potassium, rubidium, cesium, francium, alkyls, aryls, a carboxyl group, carboxylate esters, thiophosphate, N-acetyl cysteine, mercaptoacetic acid, mercaptopropionic acid, thiolsalicylate, organic groups or biological groups, n independently equals 1-10, m=1-6, Y comprises hydrogen, polymers, silicas or silica supported substrates, and Z comprises hydrogen, alkyls, aryls, a carboxyl group, carboxylate esters, a hydroxyl group, NH2, HSO3, halogens, a carbonyl group, organic groups, biological groups, polymers, silicas or silica supported substrates.
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(2011/04/19)

Efficient synthesis of primary 2-aminothiols from 2-aminoalcohols and methyldithioacetate
Various primary 2-aminothiols have been prepared by a general and efficient method, in three steps, starting from commercially available 2-aminoalcohols and methyldithioacetate as a convenient source of sulfur.
Mercey, Guillaume,Brégeon, Delphine,Gaumont, Annie-Claude,Levillain, Jocelyne,Gulea, Mihaela
supporting information; scheme or table
p. 6553 - 6555
(2009/04/05)

Resolution of DL-racemic mixtures
The present invention relates to a process for the resolution of DL-racemic mixtures of compounds which crystalize in the form of a conglumerate. Both, the D and L-enantiomers are obtained according to the invention in a industrially feasable process by adding chiral enantioselective polymers to the supersaturated solution of the racemat to inhibit crystalization of one enantiomer. Next a DL-racemic mixture of said compound is suspended in about twice the amount of the crystallized enantiomer. Consequently, the opposite enantiomer could be recovered by said suspension by physical separation.
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Page column 8-9

(2008/06/13)

Salts of L-carnitine and lower alkanoyl L-carnitine
The present invention relates to stable, non-hygroscopic salts of L-carnitine and lower alkanoyl L-carnitine endowed with enhanced nutritional and /or therapeutical efficacy with respect to their inner salts congeners and tom solid compositions containing such salts particularly suited to oral administration.
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(2008/06/13)

Synthesis of Peptides Containing S-(N-Alkylcarbamoyl)cysteine Residues, Metabolites of N-Alkylformamides in Rodents and in Humans
Hydrochloride salts of S-(N-methylcarbamoyl), S-(N-ethylcarbamoyl), and S-(N,N-dimethylcarbamoyl) derivatives of cysteine, N-acetylcysteine, and cysteinylglycine have been prepared.S-(N-Methylcarbamoyl)glutathione hydrochloride has also been synthesized.Protecting groups for amino and carboxylic acid functions were selected for their ability to solubilize the peptides in dichloromethane in which solvent the thiols were treated with alkyl isocyanates and with N,N-dimethylcarbamoyl chloride.Removal of S-(amidomethyl) protecting groups using mercury(II) acetate was found to cause some loss of N-(tert-butoxycarbonyl) groups.Elimination of disulfide was evident during coupling of disulfide derivatives of cysteine using mixed anhydride methods but not with a carbodiimide coupling agent.Mixed disulfide protections were reductively cleaved by propane-1,3-dithiol.Many of the deprotected S-carbamoyl amino acids and peptides are metabolites of the corresponding N-alkylformamides in rodents and in humans.
Threadgill, Michael D.,Gledhill, Adrian P.
p. 2940 - 2949
(2007/10/02)

Optical resolution of DL-cysteine
Disclosed is a method of optical resolution of DL-cysteine utilizing optically active mandelic acid. The method facilitates commercial production of optically active cysteine, particularly L-cysteine which is in great demand.
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(2008/06/13)

Amino-acids and Peptides. Part 45. The Protection of the Thiol Function of Cysteine and the Imidazole-N of Histidine by the Diphenyl-4-pyridylmethyl Group
S-(Diphenyl-4-pyridylmethyl)-L-cysteine (1) and its derivatives (2)-(7) have been prepared and used in peptide synthesis.In contrast to the analogous S-trityl group, this protection is stable in acid but it is cleaved readily by zinc-acetic acid, by mercury(II) acetate, by iodine, and by electrolytic reduction.N(Im)-Diphenyl-4-pyridylmethyl-L-histidine derivatives (9)-(13) are also reported; the protecting group is again stable to acid but cleaved by hydrogenolysis, by zinc-acetic acid, and by electrolytic reduction, and it has been used in the synthesis of L-histidyl-L-leucine, -L-phenylalanine, and -glycine.
Coyle, Susan,Hallett, Allan,Munns, Michael S.,Young, Geoffrey T.
p. 522 - 528
(2007/10/02)