Coupling of Steroid O-(Carboxymethyl)oxime Derivatives with Amino Alcohols

1996 ◽  
Vol 61 (2) ◽  
pp. 288-297 ◽  
Author(s):  
Vladimír Pouzar ◽  
Ivan Černý
Keyword(s):  
Amino Acids ◽  
Hydroxy Group ◽  
Building Blocks ◽  
Amino Alcohols ◽  
New Approach ◽  
Alternative Synthesis ◽  
Oxime Derivatives ◽  
A Chain ◽  
Derivatives Of

New approach to the preparation of steroids with connecting bridge, based on an O-carboxymethyloxime (CMO) structure, and with terminal hydroxy group, is presented. 17-CMO derivatives of 3β-acetoxy- and 3β-methoxymethoxyandrost-5-en-17-one were condensed with α,ω-amino alcohols to give derivatives with a chain of seven to nine atoms. After THP-protection, these compounds were converted to 3-keto-4-ene derivatives. An alternative synthesis consisted in transformation of 17-CMO derivatives with bonded amino acids by reduction of the terminal carboxyl. The resulting compounds were designed as building blocks for the preparation of bis-haptens for sandwich immunoassays.

Synthesis of Sterically Congested Carbamates of Carbohydrates through Organic Base Catalysis

Synthesis ◽  
2019 ◽  
Vol 51 (15) ◽  
pp. 2897-2908 ◽  
Author(s):  
Anji Chen ◽  
Dan Wang ◽  
Lalith P. Samankumara ◽  
Guijun Wang
Keyword(s):  
Hydroxy Group ◽  
Current Method ◽  
Building Blocks ◽  
Base Catalysis ◽  
Organic Base ◽  
Molecular Assemblies ◽  
Effective Catalyst ◽  
Organic Bases ◽  
Derivatives Of ◽  
General Method

4,6-O-Benzylidene acetal protected α-methoxy d-glucose and d-glucosamine are useful building blocks for the syntheses of carbohydrate derivatives and functional molecular assemblies. In this research, we have developed a general method for the preparation of C-3 carbamate derivatives of densely functionalized glucose and glucosamine with isocyanates using organic bases as catalysts. Without a suitable catalyst, the C-3 hydroxy group of the glucosamine derivative could not be converted into the corresponding carbamates when treated with isocyanates. Several organic bases were screened as the catalysts for the reactions, and we discovered that 5.0 mol% of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) was an effective catalyst for the carbamoylation reaction. A library of both alkyl and aryl carbamate derivatives of the two sterically congested carbohydrates have been effectively synthesized using the current method.

scholarly journals SYNTHESIS CHARACTERIZATION AND ANTIMICROBIAL ACTIVITIES STUDIES OF N-{2-(4-CHLOROPHENYL) ACETYL} AMINO ALCOHOLS DERIVED FROM α-AMINO ACIDS

2020 ◽  
pp. 11-16
Author(s):  
G. Venkateshappa ◽  
G. Shivaraju ◽  
P. Raghavendra Kumar
Keyword(s):  
Amino Acids ◽  
Amino Alcohols ◽  
Antimicrobial Activities ◽  
Docking Studies ◽  
Moderate Activity ◽  
E Coli ◽  
Synthetic Drugs ◽  
Antimicrobial Studies ◽  
Ft Ir ◽  
Derivatives Of

Amino acids play important roles in organisms to sustain in living state and perform as body constituents, enzymes and antibodies. At insalubrious situations, use of amino acids derivatives as drugs in the maintenance of normal health is better choice than common unnatural synthetic drugs. This is due to the fact that the amino acids derivatives may be more bio-compatible, biodegradable and eliminate easily than others.  In this sense we have made an effort and report herein the synthesis of N-{2-(4-chlorophenyl) acetyl} amino alcohols synthesised by reduction of N-{2-(4-chlorophenyl)acetyl} derivatives of (S)-amino acids such as (S)-phenylalanine, (S)-alanine, (S)-methionine, (S)-leucine, (S)-tryptophan and (S)-proline. These newly synthesized amino acids derivatives were analysed by proton, carbon-13 NMR and FT-IR spectroscopy. The composition of solid derivatives was determined by elemental analysis. Further, antimicrobial activities of these derivatives were assessed on usual bacteria K. aerogenes, E. coli, S. aureus and P. desmolyticum and fungi A. flavus and C. albicans. The compounds were witnessed moderate activity than authorised antibacterial and fungal agents Ciprofloxacin and Fluconazole respectively. The antimicrobial studies also revealed that, these derivatives could be better antifungal agents than antibacterial agents. Finally we compared the experimental results of antimicrobial activities with docking studies.  

ChemInform Abstract: Cyclopropyl Building Blocks in Organic Synthesis. Part 51. An Easy Access to 1-Azaspiropentane-2-carboxamides - The First Derivatives of a New Type of Amino Acids.

ChemInform ◽  
2010 ◽  
Vol 30 (51) ◽  
pp. no-no
Author(s):  
Markus Tamm ◽  
Michael Thutewohl ◽  
Carsten B. Ricker ◽  
M. Teresa Bes ◽  
Armin de Meijere
Keyword(s):  
Amino Acids ◽  
Organic Synthesis ◽  
Building Blocks ◽  
Easy Access ◽  
New Type ◽  
Derivatives Of

17-(O-(2-Carboxyethyl)oxime) Derivatives of Androstanes of 3-Hydroxy-5α-, -5β-, -5-ene and 3-Oxo-4-ene Series

1995 ◽  
Vol 60 (1) ◽  
pp. 137-149 ◽  
Author(s):  
Vladimír Pouzar ◽  
Ivan Černý
Keyword(s):  
Nmr Spectroscopy ◽  
Hydroxy Group ◽  
Alkyl Acrylate ◽  
Subsequent Hydrolysis ◽  
Jones Reagent ◽  
Oxime Derivatives ◽  
Derivatives Of ◽  
C Nmr

Androstane 17-(O-(2-carboxyethyl)oxime) derivatives were prepared either by the reaction of 17-keto derivatives with corresponding substituted hydroxylamine or by the addition of 17-oximino derivatives to the alkyl acrylate and subsequent hydrolysis. Oxidation of the hydroxy group in position 3 in derivatives of this type was performed either by the Oppenauer reaction, transforming 5-ene derivatives into 3-oxo-4-enes, or with Jones reagent in the case of saturated 5α- or 5β-derivatives. Configuration 17E in the whole series of oximes was confirmed by the 1H and 13C NMR spectroscopy.

Enantioenriched cyanohydrin O-phosphates: Synthesis and applications as chiral building blocks

2007 ◽  
Vol 79 (2) ◽  
pp. 213-221 ◽  
Author(s):  
Alejandro Baeza ◽  
José M. Sansano ◽  
José M. Saá ◽  
Carmen Nájera
Keyword(s):  
Natural Products ◽  
Building Blocks ◽  
Amino Alcohols ◽  
Aluminum Complexes ◽  
Hydroxy Esters ◽  
Derivatives Of

Aluminum complexes of the chiral (R)- or (S)-3,3'-bis(diethylaminomethyl)-1,1'-bi-2,2'-naphthol (BINOLAM) ligand behave as efficient catalysts for the enantioselective cyanation-O-functionalization of aldehydes, thereby leading to enantiomerically enriched O-silyl, O-methoxycarbonyl, or O-phosphate derivatives of cyanohydrins. The enantioenriched cyanohydrin-O-phosphates are useful for the synthesis of several enantioenriched compounds such as α-hydroxy esters, β-amino alcohols, and γ-substituted α,β-unsaturated nitriles. Natural products such as (-)-aegeline and (-)-tembamide have been prepared in this manner.

The Relative Stability of Internal Metal Complexes. II. Metal Derivatives of 8-Hydroxyquinoline 5-Sulphonic Acid and a Series of Monocarboxylic Mono-α-amino Acids including Histidine

1949 ◽  
Vol 2 (4) ◽  
pp. 579 ◽  
Author(s):  
LE Maley ◽  
DP Mellor
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Metal Complexes ◽  
Stability Constants ◽  
Sulphonic Acid ◽  
Mathematical Treatment ◽  
Metal Derivatives ◽  
A Chain ◽  
The Stability ◽  
Derivatives Of

Stability constants of ct series of metal complexes derived from the series of α-amino acids, glycine, alanine, leucine, valine, histidine, and 8-hydroxyquinoline 5-sulphonic acid have been determined by an electrometric method. The metals fall in the same order, as regards stability of their complexes, as was found for the chelating molecules studied in Part I of this series. As the length of the a chain of the amino acid increases, there is a small decrease in the stability of the amino acid complexes of any one metal. The cobalt II complex of histidine is much more stable than cobalt II complexes derived from any of the other α-amino acids. It is suggested that this explains why histidine is able to nullify the inhibiting action of cobalt on the growth and respiration of various aerobic and anaerobic organisms. Though there is no great difference in the stability of corresponding metal complexes derived from 8-hydroxyquinoline and 8-hydroxyquinoline 5-sulphonic acid (when allowance is made for different solvents used in making the measurements), there is a marked difference in the bacteriostatic action of these two chelating molecules. A reason for this difference is suggested. The stability constants of any chelating reaction involving the liberation of any number of hydrogen ions can be evaluated by using the generalized mathematical treatment which has been set out in this series of papers.

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