592,990 Works

Synthesis of fluorescent aminophosphonates by green chemistry procedures

Anna Kuśnierz & Ewa Chmielewska
Fluorescent aminophosphonates were obtained using optimized conditions of the microwave-stimulated Kabachnik-Fields reaction. Unfortunately, in the case of more demanding, bulky amines and aldehydes this reaction failed to give the desired products.

The synthesis of new fluorinated or nonfluorinated sugar phosphonates and phosphoramidates as building blocks in the synthesis of modified hyaluronic acid subunits

Katarzyna Koroniak-Szejn, Joanna Tomaszewska & Henryk Koroniak
The synthesis of several new fluorinated or nonfluorinated sugar phosphonates and phosphoramidates as building blocks for the synthesis of modified hyaluronic acid subunits is described. These compounds were prepared from d-glucose and d-glucosamine hydrochloride. The syntheses of phosphonates and phosphoramidates are based on arbuzov and staudinger reactions. The products were fully characterized by 1H, 13C, 19F, 31P NMR, and ESI MS spectroscopy.

The synthesis of new fluorinated or nonfluorinated sugar phosphonates and phosphoramidates as building blocks in the synthesis of modified hyaluronic acid subunits

Katarzyna Koroniak-Szejn, Joanna Tomaszewska & Henryk Koroniak
The synthesis of several new fluorinated or nonfluorinated sugar phosphonates and phosphoramidates as building blocks for the synthesis of modified hyaluronic acid subunits is described. These compounds were prepared from d-glucose and d-glucosamine hydrochloride. The syntheses of phosphonates and phosphoramidates are based on arbuzov and staudinger reactions. The products were fully characterized by 1H, 13C, 19F, 31P NMR, and ESI MS spectroscopy.

The formation of dimethyl amino(pyrene-1-yl)methylphosphonates in the Kabachnik-Fields reaction with dibenzyl phosphite, pyrene-1-carboxaldehyde and a non-aromatic amine in methanol

Jarosław Lewkowski & Maria Rodriguez Moya
The Kabachnik-Fields reaction of pyrene-1-carboxaldehyde with dibenzyl phosphite and aliphatic amines in methanol led to the formation of dimethyl amino(pyren-1-yl)methyl-phosphonates, in some cases accompanied by dimethyl hydroxy(pyren-1-yl)methyl-phosphonate. These results are exclusive for the above compounds, in all other studied cases (aromatic aldehydes, aromatic amines) the mixtures of several aminophosphonates were obtained.

The formation of dimethyl amino(pyrene-1-yl)methylphosphonates in the Kabachnik-Fields reaction with dibenzyl phosphite, pyrene-1-carboxaldehyde and a non-aromatic amine in methanol

Jarosław Lewkowski & Maria Rodriguez Moya
The Kabachnik-Fields reaction of pyrene-1-carboxaldehyde with dibenzyl phosphite and aliphatic amines in methanol led to the formation of dimethyl amino(pyren-1-yl)methyl-phosphonates, in some cases accompanied by dimethyl hydroxy(pyren-1-yl)methyl-phosphonate. These results are exclusive for the above compounds, in all other studied cases (aromatic aldehydes, aromatic amines) the mixtures of several aminophosphonates were obtained.

Synthese de 1,3,2-dioxaphosphorinanes diastereoisomeres: Influence de la conformation des 1,3-diols de depart sur leurs structures et conformations

Dorra Kanzari-Mnallah, Med Lotfi Efrit & Azaiez Ben Akacha
1,3-Diol reacts with phosphorus trichloride to produce diastereomeric 1,3,2-dioxaphosphorinanes. To find the predominant conformations, the influence of the diol precursors is studied and density functional theory calculation (DFT) is used. Then, hydrolysis of chlorophosphite leads to two cyclodialcoxyphosphites which are identified by NMR (31P, 1 H, 13C, MR-SM). Also, the steps of synthesis of hydrazone 1-(5,5-diethyl-2-oxo-1,3,2-dioxaphosphoranyl)-3-phenyl-propanone are studied by 31P NMR. Résumé La conformation de départ du 1,3-diol influe sur la conformation des dérivés de...

Synthese de 1,3,2-dioxaphosphorinanes diastereoisomeres: Influence de la conformation des 1,3-diols de depart sur leurs structures et conformations

Dorra Kanzari-Mnallah, Med Lotfi Efrit & Azaiez Ben Akacha
1,3-Diol reacts with phosphorus trichloride to produce diastereomeric 1,3,2-dioxaphosphorinanes. To find the predominant conformations, the influence of the diol precursors is studied and density functional theory calculation (DFT) is used. Then, hydrolysis of chlorophosphite leads to two cyclodialcoxyphosphites which are identified by NMR (31P, 1 H, 13C, MR-SM). Also, the steps of synthesis of hydrazone 1-(5,5-diethyl-2-oxo-1,3,2-dioxaphosphoranyl)-3-phenyl-propanone are studied by 31P NMR. Résumé La conformation de départ du 1,3-diol influe sur la conformation des dérivés de...

Aromaticity of 1,4-dehydrotropylium ion and its mono- and poly-phospha analogues

Aishvaryadeep Kaur, Manjinder Kour, Raakhi Gupta & Raj K. Bansal
The tropylium ion and its mono- and poly-phospha analogues on removal of two hydrogen atoms from 1,4-positions accompanied by the formation of a σ C–C bond afford 1,4-dehydrotropylium ion and its mono- and poly-phospha analogues. Aromaticity of these compounds along with 3-aza-1,4-dehydrotropylium ion, 1,4-dehydrotropilidine and its 3-phospha-analogoue has been investigated at the DFT(B3LYP/6-31+G*) level using geometry, ASE, 1H NMR chemical shifts, NICS and magnetic susceptibility exaltation descriptors. 1,4-Dehydrotropylium ion and its mono- and poly-phospha analogues...

Aromaticity of 1,4-dehydrotropylium ion and its mono- and poly-phospha analogues

Aishvaryadeep Kaur, Manjinder Kour, Raakhi Gupta & Raj K. Bansal
The tropylium ion and its mono- and poly-phospha analogues on removal of two hydrogen atoms from 1,4-positions accompanied by the formation of a σ C–C bond afford 1,4-dehydrotropylium ion and its mono- and poly-phospha analogues. Aromaticity of these compounds along with 3-aza-1,4-dehydrotropylium ion, 1,4-dehydrotropilidine and its 3-phospha-analogoue has been investigated at the DFT(B3LYP/6-31+G*) level using geometry, ASE, 1H NMR chemical shifts, NICS and magnetic susceptibility exaltation descriptors. 1,4-Dehydrotropylium ion and its mono- and poly-phospha analogues...

Synthesis and X-ray single crystal structure analysis of a new 2-chlorobenzyl ammonium salt of phosphonic acid

Hamideh Aghahosseini, Ali Ramazani, Katarzyna Ślepokura, Tadeusz Lis & Sang Woo Joo
An efficient synthesis of a new 2-chlorobenzyl ammonium salt of phosphonic acid from the reaction of diethyl phosphite with 2-chlorobenzyl amine is described at moderate temperature in catalyst- and solvent-free conditions. The structure of this phosphonic acid salt was confirmed by FT-IR, 1H, 13C, and 31P NMR spectroscopy, and single crystal X-ray structure analysis.

Synthesis and X-ray single crystal structure analysis of a new 2-chlorobenzyl ammonium salt of phosphonic acid

Hamideh Aghahosseini, Ali Ramazani, Katarzyna Ślepokura, Tadeusz Lis & Sang Woo Joo
An efficient synthesis of a new 2-chlorobenzyl ammonium salt of phosphonic acid from the reaction of diethyl phosphite with 2-chlorobenzyl amine is described at moderate temperature in catalyst- and solvent-free conditions. The structure of this phosphonic acid salt was confirmed by FT-IR, 1H, 13C, and 31P NMR spectroscopy, and single crystal X-ray structure analysis.

Diethyl boronobenzylphosphonates as substrates in Suzuki–Miyaura reaction

Agata Rydzewska, Anna Mangold, Weronika Wanat & Paweł Kafarski
N-substituted boronobenzylphosphonates were evaluated as substrates in Suzuki–Miyaura coupling catalyzed by tetrakis(triphenylphosphine)palladium(0) and complex of palladium acetate and (2-biphenyl)dicyclohexylphosphine. It was proven that they may be considered as useful substrates for the preparation of functionalized aminophosphonates.

Diethyl boronobenzylphosphonates as substrates in Suzuki–Miyaura reaction

Agata Rydzewska, Anna Mangold, Weronika Wanat & Paweł Kafarski
N-substituted boronobenzylphosphonates were evaluated as substrates in Suzuki–Miyaura coupling catalyzed by tetrakis(triphenylphosphine)palladium(0) and complex of palladium acetate and (2-biphenyl)dicyclohexylphosphine. It was proven that they may be considered as useful substrates for the preparation of functionalized aminophosphonates.

Central immunological position of the human histo (blood) group O(H).

Peter Arend
Prokaryotic "blood group A/B-like" antigenic structures apparently induce basically cross-reactive anti-A/B immunoglobulins, which due to clonal selection neither arise in blood group A nor in B individuals but occur exclusively in blood group O. While bacterial endotoxins non-specifically stimulate the formation of all immunoglobulins, most likely involving the anti-A/B isoagglutinins, a definite, adaptive immunological induction of these agglutinins appears to be restricted to blood group O(H) individuals. In the non-O blood groups, anti-A/B reactivity is...

Conversion of nitriles to 1-aminophosphonic acids and preparation of phosphahomocysteines of high enantiomeric excess

Renzhe Qian, Jeannie Horak & Friedrich Hammerschmidt
A variety of nitriles was reduced to diisobutylaluminum salts of aldimines, to which diisopropyl phosphite was added. The corresponding 1-aminophosphonates were either deprotected to give racemic 1-aminophosphonic acids or reacted with Boc2O to yield N-Boc-protected 1-aminophosphonates. The enantiomers of 2-benzylthio-1-(t-butoxycarbonylamino)propylphosphonate were obtained from the racemate by chiral HPLC and converted to phosphonic acid analogs of (R)- and (S)-homocysteine, (R)- and (S)-2-aminobutyric acid and (S)-methionine, all of ee >97% as determined by chiral HPLC.

Conversion of nitriles to 1-aminophosphonic acids and preparation of phosphahomocysteines of high enantiomeric excess

Renzhe Qian, Jeannie Horak & Friedrich Hammerschmidt
A variety of nitriles was reduced to diisobutylaluminum salts of aldimines, to which diisopropyl phosphite was added. The corresponding 1-aminophosphonates were either deprotected to give racemic 1-aminophosphonic acids or reacted with Boc2O to yield N-Boc-protected 1-aminophosphonates. The enantiomers of 2-benzylthio-1-(t-butoxycarbonylamino)propylphosphonate were obtained from the racemate by chiral HPLC and converted to phosphonic acid analogs of (R)- and (S)-homocysteine, (R)- and (S)-2-aminobutyric acid and (S)-methionine, all of ee >97% as determined by chiral HPLC.

1-(N-Acylamino)alkylphosphonic acids—Deacylation in aqueous solutions

Marek Cypryk, Jozef Drabowicz, Bartlomiej Gostynski, Marcin H. Kudzin, Zbigniew H. Kudzin & Pawel Urbaniak
The 1-(N-acylamino)alkylphosphonic acids (AC)-AAP belong to the interesting and potentially of pharmacological importance group of 1-aminoalkylphosphonic acids derivatives. Since susceptibility of (AC)-AAP on hydrolytic deacylation can form important factor influencing their biological activity, we have undertaken deacylation investigations of these compounds in aqueous media. In this article, we present our results on deacylation of various types of 1-(N-acylamino)alkylphosphonic acids (AC)-AAP, including 1-(N-acetylamino)alkyl-phosphonic Ac-AAP, 1-(N-chloroacetylamino)alkylphosphonic acids Mca-AAP, 1-(N-trifluoroacetylamino)alkylphosphonic acids TFA-AAP, and 1-(N-benzoylamino)-alkylphosphonic Bz-AAP, derived from representative...

1-(N-Acylamino)alkylphosphonic acids—Deacylation in aqueous solutions

Marek Cypryk, Jozef Drabowicz, Bartlomiej Gostynski, Marcin H. Kudzin, Zbigniew H. Kudzin & Pawel Urbaniak
The 1-(N-acylamino)alkylphosphonic acids (AC)-AAP belong to the interesting and potentially of pharmacological importance group of 1-aminoalkylphosphonic acids derivatives. Since susceptibility of (AC)-AAP on hydrolytic deacylation can form important factor influencing their biological activity, we have undertaken deacylation investigations of these compounds in aqueous media. In this article, we present our results on deacylation of various types of 1-(N-acylamino)alkylphosphonic acids (AC)-AAP, including 1-(N-acetylamino)alkyl-phosphonic Ac-AAP, 1-(N-chloroacetylamino)alkylphosphonic acids Mca-AAP, 1-(N-trifluoroacetylamino)alkylphosphonic acids TFA-AAP, and 1-(N-benzoylamino)-alkylphosphonic Bz-AAP, derived from representative...

Michael additions to double bonds of esters of N-protected (s)-phenylalanyldehydroalanine (X-(s)-Phe-ΔAla-OMe) and its phosphonic acid counterpart (X-(s)-Phe-ΔAla-PO(OEt)2)

Paweł Lenartowicz, Błażej Dziuk, Bartosz Zarychta, Maciej Makowski & Paweł Kafarski
Electrophilic addition of amines, thiols and bromide to the double bonds of model dehydrodipeptides and dehydrophosphonodipeptide was studied. The double bond in these two classes of peptides reacted similarly and gave the same products. These results indicate that dehydropeptides are very good candidates as substrates for modifications of peptide side-chains.

Michael additions to double bonds of esters of N-protected (s)-phenylalanyldehydroalanine (X-(s)-Phe-ΔAla-OMe) and its phosphonic acid counterpart (X-(s)-Phe-ΔAla-PO(OEt)2)

Paweł Lenartowicz, Błażej Dziuk, Bartosz Zarychta, Maciej Makowski & Paweł Kafarski
Electrophilic addition of amines, thiols and bromide to the double bonds of model dehydrodipeptides and dehydrophosphonodipeptide was studied. The double bond in these two classes of peptides reacted similarly and gave the same products. These results indicate that dehydropeptides are very good candidates as substrates for modifications of peptide side-chains.

"Cross-platform normalization enables analysis of microarray and RNA-seq data simultaneously" - Fileset

Jaclyn Taroni & Casey Greene
This is the full output of the pipeline for "Cross-platform normalization enables analysis of microarray and RNA-seq data simultaneously" -- a project for assessing which normalization methods enable the combination of RNA-seq and microarray data for several applications, including supervised machine learning and differential expression analysis.

See also our github repository: https://github.com/greenelab/RNAseq_titration_results

A preprint of this work is available on bioRxiv: https://doi.org/10.1101/118349

"Cross-platform normalization enables analysis of microarray and RNA-seq data simultaneously" - Fileset

Jaclyn Taroni & Casey Greene
This is the full output of the pipeline for "Cross-platform normalization enables analysis of microarray and RNA-seq data simultaneously" -- a project for assessing which normalization methods enable the combination of RNA-seq and microarray data for several applications, including supervised machine learning and differential expression analysis.

See also our github repository: https://github.com/greenelab/RNAseq_titration_results

A preprint of this work is available on bioRxiv: https://doi.org/10.1101/118349

Emission factors of fine particulate matter, organic and elemental carbon, carbon monoxide, and carbon dioxide for four solid fuels commonly used in residential heating by the Navajo Nation

Wyatt M. Champion, Lea Connors & Lupita D. Montoya
Most homes in the Navajo Nation use wood as their primary heating fuel, often in combination with locally-mined coal. Previous studies observed health effects linked to this solid-fuel use in several Navajo communities. Emission factors (EF) for common fuels used by the Navajo have not been reported using a relevant stove type. In this study, two softwoods (Ponderosa Pine and Utah Juniper) and two high-volatile bituminous coals (Black Mesa and Fruitland) were tested with an...

Emission factors of fine particulate matter, organic and elemental carbon, carbon monoxide, and carbon dioxide for four solid fuels commonly used in residential heating by the Navajo Nation

Wyatt M. Champion, Lea Connors & Lupita D. Montoya
Most homes in the Navajo Nation use wood as their primary heating fuel, often in combination with locally-mined coal. Previous studies observed health effects linked to this solid-fuel use in several Navajo communities. Emission factors (EF) for common fuels used by the Navajo have not been reported using a relevant stove type. In this study, two softwoods (Ponderosa Pine and Utah Juniper) and two high-volatile bituminous coals (Black Mesa and Fruitland) were tested with an...

Fungal levels in houses in the Fukushima Daiichi nuclear power plant evacuation zone after the Great East Japan Earthquake

Naohide Shinohara, Masahiro Tokumura, Kazuhiro Hashimoto, Katsuyoshi Asano & Yuji Kawakami
Residences located within 20 km of the damaged Fukushima Daiichi nuclear power plant were evacuated shortly after the Great East Japan Earthquake. The levels of airborne and surface fungi were measured in six houses in the evacuation zone in August 2012 and February 2013. Airborne fungal levels in all of the houses in the summer were higher than the environmental standard levels for residential houses published in Architectural Institute of Japan (>1,000 CFU/m3). In two...

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