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Molecules (Basel, Switzerland) Apr 2008A solvent-free approach for the regioselective synthesis of beta-amino alcohols in shorter reaction times and higher yields, compared to conventional heating is...
A solvent-free approach for the regioselective synthesis of beta-amino alcohols in shorter reaction times and higher yields, compared to conventional heating is described. It involves microwave (MW) exposure of undiluted reactants in the presence of sulphated zirconia (SZ) or sulphated zirconia over MCM-41 (SZM) as catalyst. Both acid materials can be easily recovered and reused.
Topics: Amino Alcohols; Catalysis; Chromatography, Gas; Ethylene Oxide; Microwaves; Silicon Dioxide; Solvents; Stereoisomerism; Sulfates; X-Ray Diffraction; Zirconium
PubMed: 18463599
DOI: 10.3390/molecules13040977 -
Journal of Dairy Science Jan 1970
Topics: Amino Acids; Amino Alcohols; Animals; Arginine; Autoanalysis; Cattle; Chromatography, Ion Exchange; Cystine; Ejaculation; Fertility; Glutamates; Male; Methionine; Semen; Spermatozoa; Sulfoxides; Time Factors; Valine
PubMed: 5413074
DOI: 10.3168/jds.S0022-0302(70)86152-5 -
Nature Jul 2015The carbon-nitrogen double bonds in imines are fundamentally important functional groups in organic chemistry. This is largely due to the fact that imines act as...
The carbon-nitrogen double bonds in imines are fundamentally important functional groups in organic chemistry. This is largely due to the fact that imines act as electrophiles towards carbon nucleophiles in reactions that form carbon-carbon bonds, thereby serving as one of the most widely used precursors for the formation of amines in both synthetic and biosynthetic settings. If the carbon atom of the imine could be rendered electron-rich, the imine could react as a nucleophile instead of as an electrophile. Such a reversal in the electronic characteristics of the imine functionality would facilitate the development of new chemical transformations that convert imines into amines via carbon-carbon bond-forming reactions with carbon electrophiles, thereby creating new opportunities for the efficient synthesis of amines. The development of asymmetric umpolung reactions of imines (in which the imines act as nucleophiles) remains uncharted territory, in spite of the far-reaching impact such reactions would have in organic synthesis. Here we report the discovery and development of new chiral phase-transfer catalysts that promote the highly efficient asymmetric umpolung reactions of imines with the carbon electrophile enals. These catalysts mediate the deprotonation of imines and direct the 2-azaallyl anions thus formed to react with enals in a highly chemoselective, regioselective, diastereoselective and enantioselective fashion. The reaction tolerates a broad range of imines and enals, and can be carried out in high yield with as little as 0.01 mole per cent catalyst with a moisture- and air-tolerant operational protocol. These umpolung reactions provide a conceptually new and practical approach to chiral amino compounds.
Topics: Acrolein; Air; Amino Alcohols; Carbon; Catalysis; Chemistry Techniques, Synthetic; Electrons; Humidity; Imines; Nitrogen
PubMed: 26201597
DOI: 10.1038/nature14617 -
Angewandte Chemie (International Ed. in... Dec 2014The first catalytic enantioselective aminolysis of trans-2,3-epoxy alcohols has been accomplished. This stereospecific ring-opening process was efficiently promoted by a...
The first catalytic enantioselective aminolysis of trans-2,3-epoxy alcohols has been accomplished. This stereospecific ring-opening process was efficiently promoted by a tungsten/bis(hydroxamic acid) catalytic system, furnishing various anti-3-amino-1,2-diols with excellent regiocontrol and high enantioselectivities (up to 95% ee). Moreover, virtually enantiopure 3-amino-1,2-diols could be obtained by the sequential combination of two reactions that both involve the use of a chiral catalyst.
Topics: Amino Alcohols; Catalysis; Tungsten
PubMed: 25328028
DOI: 10.1002/anie.201408732 -
Parasites & Vectors Jun 2016Strongyloidiasis is a parasitic disease widely present in tropical and subtropical areas. Strongyloides stercoralis represents the main species that infects human...
BACKGROUND
Strongyloidiasis is a parasitic disease widely present in tropical and subtropical areas. Strongyloides stercoralis represents the main species that infects human beings. Ivermectin is the current drug of choice; however, issues related with treatment failure in patients with diabetes or infected with T-lymphotropic virus-1 make the identification of new molecules for alternative treatment a priority. In the present study, the activity of sphingosine-related aminoalcohol and diamine were evaluated against Strongyloides venezuelensis third-stage larva (L3) cultures and experimental infections in mice.
METHODS
The efficacy of each compound against L3 was assessed using both XTT (2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) assay and microscopic observation with concentrations ranging from 1 to 350 μM. Cytotoxicity was evaluated using J774.2 macrophage cell line and XTT assay. Lethal concentration 50 (LC50), selectivity index (SI) and structure-activity relationships were established. The activity compounds 4 (2-(ethylamino) hexadecan-1-ol), 6 (2-(butylamino) hexadecan-1-ol), 17 (tert-butyl N-(1-aminododecan-2-yl) carbamate) and 18 (tert-butyl N-(1-aminohexadecan-2-yl) carbamate) were further assessed against experimental S. venezuelensis infections in CD1 mice measuring reductions in the numbers of parthenogenetic females and egg passed in faeces. Mice were infected with 3,000 L3 and treated with 20 mg/kg/day for five days.
RESULTS
In the screening study of 15 aminoalcohols [lauryl (n = 9); palmityl (n = 13); stearyl (n = 15) and alcohol derivatives], the presence of a palmitol chain was associated with the highest efficacy against L3 (LC50 31.9-39.1 μM). Alkylation of the 2-amino group with medium size fragments as ethyl or n-butyl showed the best larvicidal activity. The dialkylation did not improve efficacy. Aminoalcohols 4 and 6 showed the highest SI (1.5 and 1.6, respectively). With respect to diamine derivative compounds, a chain size of sixteen carbon atoms (palmitoyl chain, n = 13), and the alkylation of the 2-amino group with medium-sized fragments, were associated with the highest lethal activities. The presence of carbamoyl group in diamines 17 and 18 yielded high SI (1.7 and 1.4, respectively). Infected mice treated with aminoalcohol 6 showed reduction in parthenogenetic females (59 %) and eggs in faeces (51 %).
CONCLUSIONS
These results support the potentiality of aminoalcohol and diamine sphingosine-related compounds as suitable prototypes for developing new promising drugs against strongyloidiasis.
Topics: Amino Alcohols; Animals; Anthelmintics; Diamines; Male; Mice; Molecular Structure; Rats; Strongyloides; Strongyloidiasis; Structure-Activity Relationship
PubMed: 27353595
DOI: 10.1186/s13071-016-1648-5 -
In vitro antifungal activity of organic compounds derived from amino alcohols against onychomycosis.Brazilian Journal of Microbiology :... 2017Onychomycosis is a fungal infection of the nail caused by high densities of filamentous fungi and yeasts. Treatment for this illness is long-term, and recurrences are...
Onychomycosis is a fungal infection of the nail caused by high densities of filamentous fungi and yeasts. Treatment for this illness is long-term, and recurrences are frequently detected. This study evaluated in vitro antifungal activities of 12 organic compounds derived from amino alcohols against standard fungal strains, such as Trichophyton rubrum CCT 5507 URM 1666, Trichophyton mentagrophytes ATCC 11481, and Candida albicans ATCC 10231. The antifungal compounds were synthesized from p-hydroxybenzaldehyde (4a-4f) and p-hydroxybenzoic acid (9a-9f). Minimum inhibitory concentrations and minimum fungicidal concentrations were determined according to Clinical and Laboratory Standards Institute protocols M38-A2, M27-A3, and M27-S4. The amine series 4b-4e, mainly 4c and 4e compounds, were effective against filamentous fungi and yeast (MIC from 7.8 to 312μg/mL). On the other hand, the amide series (9a-9f) did not present inhibitory effect against fungi, except amide 9c, which demonstrated activity only against C. albicans. This allowed us to infer that the presence of amine group and intermediate carbon number (8C-11C) in its aliphatic side chain seems to be important for antifungal activity. Although these compounds present cytotoxic activity on macrophages J774, our results suggest that these aromatic compounds might constitute potential as leader molecules in the development of more effective and less toxic analogs that could have considerable implications for future therapies of onychomycosis.
Topics: Amino Alcohols; Antifungal Agents; Drug Evaluation, Preclinical; Fungi; Humans; Microbial Sensitivity Tests; Onychomycosis
PubMed: 28237676
DOI: 10.1016/j.bjm.2016.12.008 -
Journal of the American Chemical Society May 2015Aliphatic amides are selectively functionalized at the γ- and δ-positions through directed radical 1,5 and 1,6 H-abstractions, respectively. The initially formed γ-...
Aliphatic amides are selectively functionalized at the γ- and δ-positions through directed radical 1,5 and 1,6 H-abstractions, respectively. The initially formed γ- or δ-lactams are intercepted by N-iodosuccinimide and trimethylsilyl azide, leading to double and triple C-H functionalizations at the γ-, δ-, and ε-positions. This new reactivity is exploited to convert alkyls into amino alcohols and allylic amines.
Topics: Amides; Amines; Amino Alcohols; Azides; Free Radicals; Lactams; Molecular Structure; Silanes; Succinimides
PubMed: 25915558
DOI: 10.1021/jacs.5b02065 -
Chemical & Pharmaceutical Bulletin 2017A highly chemoselective conjugate addition of amino alcohols to α,β-unsaturated ester using a soft Lewis acid/hard Brønsted base cooperative catalyst was developed....
A highly chemoselective conjugate addition of amino alcohols to α,β-unsaturated ester using a soft Lewis acid/hard Brønsted base cooperative catalyst was developed. This catalysis achieved chemoselective addition of a hydroxy group over an amino group. Moreover, soft metal alkoxide generation enabled chemoselective soft conjugate addition over hard transesterification. Various amino alcohols, including unprecedented cyclic β-amino alcohol, were applicable to the present catalysis.
Topics: Amines; Amino Alcohols; Catalysis; Esters; Molecular Structure; Stereoisomerism
PubMed: 28049909
DOI: 10.1248/cpb.c16-00333 -
Molecules (Basel, Switzerland) Aug 2016Aspirination of α-aminoalcohol (sarpogrelate M1) has been performed under various general esterification conditions. In most cases, the desired aspirinate ester was...
Aspirination of α-aminoalcohol (sarpogrelate M1) has been performed under various general esterification conditions. In most cases, the desired aspirinate ester was obtained at a low yield with unexpected byproducts, the formation of which was mostly derived from the chemical properties of the tertiary α-amino group. After systematic analysis of those methods, the aspirinated sarpogrelate M1 was prepared using a two-step approach combining salicylate ester formation and acetylation.
Topics: Amino Alcohols; Aspirin; Esterification; Succinates
PubMed: 27571053
DOI: 10.3390/molecules21091126 -
Journal of the American Chemical Society Jun 2006The contribution of C-N bond-breaking/making steps to the rate of the free-radical-mediated deamination of vicinal amino alcohols by adenosylcobalamin-dependent...
The contribution of C-N bond-breaking/making steps to the rate of the free-radical-mediated deamination of vicinal amino alcohols by adenosylcobalamin-dependent ethanolamine ammonia-lyase has been investigated by 15N isotope effects (IE's) and by electron paramagnetic resonance (EPR) spectroscopy. 15N IE's were determined for three substrates, ethanolamine, (R)-2-aminopropanol, and (S)-2-aminopropanol, using isotope ratio mass spectrometry analysis of the product ammonia. Measurements with all three substrates gave measurable, normal 15N IE's; however, the IE of (S)-2-aminopropanol was approximately 5-fold greater than that of the other two. Reaction mixtures frozen during the steady state show that the 2-aminopropanols give EPR spectra characteristic of the initial substrate radical, whereas ethanolamine gives spectra consistent with a product-related radical (Warncke, K.; Schmidt, J. C.; Kee, S.-C. J. Am. Chem. Soc. 1999, 121, 10522-10528). The steady-state concentration of the radical with (R)-2-aminopropanol is about half that observed with the S isomer, and with (R)-2-aminopropanol, the steady-state level of the radical is further reduced upon deuteration at C1. The results show that relative heights of kinetic barriers differ among the three substrates such that levels or identities of steady-state intermediates differ. 15N-sensitive steps are significant contributors to V/K with (S)-2-aminopropanol.
Topics: Amino Alcohols; Catalysis; Cloning, Molecular; Deamination; Escherichia coli; Ethanolamine; Ethanolamine Ammonia-Lyase; Free Radicals; Nitrogen; Propanolamines; Salmonella typhimurium; Substrate Specificity
PubMed: 16734439
DOI: 10.1021/ja060710q