Amino Acid Catalyzed Conjugate Addition of Thiol to Dienone

2013 ◽  
Vol 834-836 ◽  
pp. 450-453
Author(s):  
Han Feng Cui ◽  
Yan Lin ◽  
Hao Fan ◽  
Li De Yu ◽  
Ping Nan Wan
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Room Temperature ◽  
Addition Product ◽  
Conjugate Addition ◽  
Acid Catalyzed

Double conjugate addition of thiols with dienones was catalyzed by amino acids at room temperature in methanol, to afford the corresponding addition product in good to excellent yields.

Self-Assembling Functionalized Amino Acids into Unusual Shapes

2011 ◽  
Vol 1312 ◽  
Author(s):  
Justin R. Barone ◽  
Naresh K. Budhavaram ◽  
Katherine J. Harvey
Keyword(s):  
Amino Acids ◽  
Hydrogen Bond ◽  
Amino Acid ◽  
Room Temperature ◽  
Vinyl Sulfone ◽  
Ethyl Vinyl ◽  
Simple Route ◽  
Self Assembling ◽  
Component Systems ◽  
Functionalized Amino Acids

ABSTRACTMulti-component small molecule systems that are amphiphilic or that can hydrogen bond end-to-end or side-to-side have been shown to self-assemble into a variety of shapes including fibers, rods, sheets, plates, spheres, and tubes. Recently, we have identified a simple route to self-assemble the same shapes from one-component systems. The structures form by attaching ethyl vinyl sulfone (EVS) to amino acids in water at room temperature. Choice of amino acid, amount of EVS substitution, and solvent conditions determine the final shape. Functionalized amino acids spontaneously form structures like fibers, spheres, tubes, and donuts when dried from solution. Here we focus on fibers and tubes.

A Study of 2,4,6-Trinitrobenzenesulfonic Acid for Automated Amino Acid Chromatography

1968 ◽  
Vol 14 (10) ◽  
pp. 967-978 ◽  
Author(s):  
Harold H Brown
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Room Temperature ◽  
Lower Sensitivity ◽  
Static System ◽  
Optimum Conditions ◽  
Trinitrobenzenesulfonic Acid ◽  
Imino Acid ◽  
Major Disadvantage ◽  
Heating Bath

Abstract The reaction of 2,4,6-trinitrobenzenesulfonic acid (TNBS) with amino acids was investigated by a static system to develop optimum conditions for application to automated amino acid chromatography. TNBS was found to be a very simple and sensitive reagent, easier to use than ninhydrin. The reaction occurs quite rapidly at room temperature, eliminating the requirement of a heating bath. The major disadvantage is a much lower sensitivity to the imino acid proline than to the amino acids.

scholarly journals Inhibition of sickling in erythrocytes by amino acids

Blood ◽  
1975 ◽  
Vol 45 (1) ◽  
pp. 45-48 ◽  
Author(s):  
NM Rumen
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Room Temperature

Abstract Sickling of erythrocytes was rapidly and quantitatively inhibited at room temperature by 3.8 mM homoserine, asparagine, and glutamine but by no other amino acid.

Stereoselectivity of montmorillonite in the adsorption and deamination of some amino acids

Clay Minerals ◽  
1992 ◽  
Vol 27 (1) ◽  
pp. 109-118 ◽  
Author(s):  
B. Siffert ◽  
A. Naidja
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Reaction Kinetics ◽  
Clay Mineral ◽  
Room Temperature ◽  
Optical Isomers ◽  
Racemic Mixtures ◽  
Deamination Reaction

AbstractOptical isomers deamination of L- and D-glutamic and aspartic amino acids and of their DL racemic mixtures has been achieved in the presence of Na-montmorillonite at pH = 6 and room temperature. The adsorption curves showed that the enantiomer adsorbed depends on the type of amino acid. Nevertheless, deamination reaction kinetics brought about a stereoselectivity of the clay mineral for the L-isomer and implicitly showed an unquestionable “structural chirality character” of the clay mineral.

Optical, dielectric & ferroelectric studies on amino acids doped TGS single crystals

RSC Advances ◽  
2016 ◽  
Vol 6 (40) ◽  
pp. 33686-33694 ◽  
Author(s):  
P. R. Deepthi ◽  
J. Shanthi
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Single Crystals ◽  
Room Temperature ◽  
Solution Growth ◽  
Slow Evaporation ◽  
Growth Technique ◽  
Optical Dielectric ◽  
Solution Growth Technique

Pure TGS and amino acid (l-arginine, l-histidine and l-alanine) doped TGS crystals were grown by a slow evaporation solution growth technique at room temperature.

N-Methylamino acids in peptide synthesis. V. The synthesis of N-tert-butyloxycarbonyl, N-methylamino acids by N-methylation

1977 ◽  
Vol 55 (5) ◽  
pp. 906-910 ◽  
Author(s):  
S. T. Cheung ◽  
N. Leo Benoiton
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Methyl Iodide ◽  
Peptide Synthesis ◽  
Room Temperature ◽  
Sodium Hydride ◽  
Amino Acid Derivatives ◽  
Enantiomerically Pure ◽  
Neutral Amino Acids ◽  
Related Data

The preparation of enantiomerically pure N-tert-butyloxycarbonyl,N-methylamino acids by N-methylation of the parent amino acid derivatives using sodium hydride and methyl iodide in tetrahydrofuran at room temperature is described for neutral amino acids including O-benzyl-protected threonine and tyrosine. Methylation of the O-benzylserine derivative under these conditions gives the N-methyldehydroalanine derivative. The β-elimination is completely suppressed, giving the corresponding N-methylserine derivative when the reaction is carried out at 5 °C. Other related data on N-methylation and N-methylamino acid derivatives are presented.

Synthesis of functionalized pyrazole derivatives by regioselective [3+2] cycloadditions of N-Boc-α-amino acid-derived ynones

2018 ◽  
Vol 73 (7) ◽  
pp. 467-480 ◽  
Author(s):  
Eva Pušavec Kirar ◽  
Uroš Grošelj ◽  
Amalija Golobič ◽  
Franc Požgan ◽  
Sebastijan Ričko ◽  
...  
Keyword(s):  
Amino Acids ◽  
Nuclear Magnetic Resonance ◽  
Amino Acid ◽  
Ring Opening ◽  
Pyrazole Derivatives ◽  
X Ray Diffraction ◽  
X Ray ◽  
Acid Catalyzed ◽  
Azomethine Imines

Abstract [3+2] cycloadditions of ynones derived from glycine and (S)-alanine and some other dipolarophiles with azomethine imines, nitrile oxides, diazoacetate, and azidoacetate were studied. The dipolarophiles were obtained from α-amino acids, either by the reduction of the carboxy function with ethynylmagnesium bromide or by propiolation of the amino function. Cu-catalyzed cycloadditions of ynones to azomethine imines were regioselective and gave the expected cycloadducts as inseparable mixtures of diastereomers. In some instances, further oxidative hydrolytic ring-opening took place to afford 3,3-dimethyl-3-(1H-pyrazol-1-yl)propanoic acids. Acid-catalyzed cycloadditions of 3-butenone were also regioselective and provided mixtures of diastereomeric cycloadducts, which were separated by chromatography. In the reactions of title ynones with alkyl diazoacetates, in situ-formed benzonitrile oxides, and tert-butyl azidoacetate, all cycloadducts were obtained as single regioisomers. The structures of all novel compounds were established by nuclear magnetic resonance and X-ray diffraction.

Stability of Famotidine in Minibags Refrigerated and/or Frozen in Total Parenteral Nutrition Solutions

DICP ◽  
1989 ◽  
Vol 23 (10_suppl) ◽  
pp. S44-S46
Author(s):  
Linda S. Bullock
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Parenteral Nutrition ◽  
Gastrointestinal Bleeding ◽  
Total Parenteral Nutrition ◽  
Critically Ill ◽  
Critically Ill Patients ◽  
Room Temperature ◽  
Acid Solutions ◽  
Amino Acid Solutions

The use of histamine2-receptor antagonists could be beneficial in critically ill patients for protection against stress-induced gastrointestinal bleeding. Famotidine, similar to cimetidine and ranitidine, is stable when mixed in dextrose 5% injection and NaCl 0.9% injection at a concentration of 200 μg/mL and stored in polyvinyl chloride bags at 4 °C for 14 days or when frozen for 28 days and subsequently refrigerated for 14 days. Furthermore, famotidine, also like cimetidine and ranitidine, is stable when added to most common total parenteral nutrition (TPN) solutions. Famotidine in concentrations of 20 mg/L and 40 mg/L is stable in crystalline amino acid solutions (20 g/L and 42.5 g/L) when refrigerated for 24 hours, then held at room temperature for 24 hours, at room temperature for 48 hours, or refrigerated for seven days. The concentration of amino acids in the TPN solutions containing 42.5 g/L also is not affected by the addition of famotidine 40 mg/L when stored under conditions similar to those stated above for 48 hours. TPN solutions remain clear and free of turbidity.

A Highly Enantioselective Amino Acid-Catalyzed Route to Functionalized α-Amino Acids

2002 ◽  
Vol 124 (9) ◽  
pp. 1842-1843 ◽  
Author(s):  
Armando Córdova ◽  
Wolfgang Notz ◽  
Guofu Zhong ◽  
Juan M. Betancort ◽  
Carlos F. Barbas
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Acid Catalyzed
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