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1.
Molecules ; 23(4)2018 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-29642559

RESUMO

The alkaline deacylation of a representative series of 1-(acylamino)alkylphosphonic acids [(AC)-AAP: (AC) = Ac, TFA, Bz; AAP = GlyP, AlaP, ValP, PglP and PheP] in an aqueous solution of KOH (2M) was investigated. The results suggested a two-stage reaction mechanism with a quick interaction of the hydroxyl ion on the carbonyl function of the amide R-C(O)-N(H)- group in the first stage, which leads to instant formation of the intermediary acyl-hydroxyl adducts of R-C(O-)2-N(H)-, visible in the 31P NMR spectra. In the second stage, these intermediates decompose slowly by splitting of the RC(O-)2-N(H)- function with the subsequent formation of 1-aminoalkylphosphonate and carboxylate ions.


Assuntos
Aminoácidos/química , Organofosfonatos/química , Acilação , Hidróxidos/química , Espectroscopia de Ressonância Magnética/métodos , Modelos Moleculares , Estrutura Molecular , Termodinâmica , Água/química
2.
Chirality ; 30(2): 131-140, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29272065

RESUMO

The first successful enantioseparation of representative O,O-diphenyl-N-arylthioureidoalkylphosphonates, (±)-Ptc-ValP (OPh)2 & (±)-Ptc-LeuP (OPh)2 and thiourylenedi(isobutyl phosphonate), Tcm[ValP (OPh)2 ]2 on analytical and semipreparative scale was achieved by high-performance liquid chromatography using polysaccharide-based chiral stationary phases (CPs). Atc-AAP (OPh)2 was obtained using modified tricomponent condensations of the corresponding aldehydes, N-arylthiourea and triphenyl phosphite whereas Tcm[ValP (OPh)2 ]2 by the condensations of aldehydes, thiourea, and triphenyl phosphite. The prepared, racemic (±)-Atc-AAP (OPh)2 [(±)-Ptc-ValP (OPh)2 , (±)-Ptc-LeuP (OPh)2 , (±)-Ptc-PglyP (OPh)2 and (±)-Ntc-PglyP (OPh)2 ] and racemic (±)-Tcm[AAP (OPh)2 ]2 [(±)-Tcm[NvaP (OPh)2 ]2 & (±)-Tcm[ValP (OPh)2 ]2 ] were adequately characterized and used for chromatographic separations on high-performance liquid chromatography-chiral stationary phases. The best results were obtained for (±)-Ptc-ValP (OPh)2 , (±)-Ptc-LeuP (OPh)2 and (±)-Tcm[ValP (OPh)2 ]2 .

3.
Dalton Trans ; 45(5): 2308-17, 2016 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-26631424

RESUMO

The reactions of 1-aminoalkylphosphonic acids with bromine-water, chlorine-water and iodine-water were investigated. The formation of phosphoric(v) acid, as a result of a halogen-promoted cleavage of the Cα-P bond, accompanied by nitrogen release, was observed. The dephosphonylation of 1-aminoalkylphosphonic acids was found to occur quantitatively. In the reactions of 1-aminoalkylphosphonic acids with other halogen-water reagents investigated by (31)P NMR, scission of the Cα-P bond was also observed, the reaction rates being comparable for bromine and chlorine, but much slower for iodine.

4.
Acta Biochim Pol ; 62(1): 139-50, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25730210

RESUMO

The approach for the unification of published proposals for the nomenclature and abbreviations of aminoalkylphosphonic acids and their derivatives is presented. Their modification was made on the basis of the IUPAC-IUB rules concerning the nomenclature and code system of proteinogenic amino acids. Our present proposal formulates the supplementary code and nomenclature system allowing unambiguous description of phosphonic analogs of proteinogenic amino acids, their analogs, homologs, metabolites, and derivatives including phosphonopeptides.


Assuntos
Ácidos Fosforosos/química , Terminologia como Assunto
5.
Acta Crystallogr C ; 63(Pt 9): o504-6, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17762118

RESUMO

The title compound, C(25)H(22)O(3)P(2).C(6)H(6)O, has a zwitterionic betaine-like structure and crystallizes as a phenol solvate. The two molecular components are held together by an almost linear intermolecular O-H...O hydrogen bond. The structure also contains three weak C-H...O and two C-H...pi(arene) interactions.


Assuntos
Organofosfonatos/química , Fenóis/química , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Solventes , Difração de Raios X
6.
Acta Crystallogr B ; 60(Pt 2): 211-8, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15017095

RESUMO

The crystal structures of three (N-phenylthioureidoalkyl- and -aryl)phosphonates, i.e. diphenyl [(3-phenylthioureido)phenylpropyl]phosphonate, diphenyl [1-(3-phenylthioureido)benzyl]phosphonate and diphenyl [2,2-dimethyl-1-(3-phenylthioureido)propyl]phosphonate, have been determined by X-ray diffraction. The conformations of the title molecules, the geometry of the thioureide fragments and molecular packing arrangements are analyzed and compared with literature data.

7.
J Chromatogr A ; 998(1-2): 183-99, 2003 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-12862383

RESUMO

A new approach for simultaneous analysis of biologically active aminoalkanephosphonic acids, namely glyphosate, phosphonoglycine, phosphonosarcosine, phosphonoalanine, phosphono-beta-alanine, phosphonohomoalanine, phosphono-gamma-homoalanine and glufosinate, is presented. This includes a preliminary 31p NMR analysis of these amino acids, their further derivatization to volatile phosphonates (phosphinates) by means of trifluoroacetic acid-trifluoroacetic anhydride-trimethyl orthoacetate reagent and subsequent analysis of derivatization products using MS and/or GC-MS (chemical ionization and/or electron impact ionization).


Assuntos
Organofosfonatos/análise , Espectroscopia de Ressonância Magnética , Espectrometria de Massas/métodos
8.
Acta Crystallogr C ; 59(Pt 1): o46-50, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12506236

RESUMO

The structures of diphenyl [3-methyl-1-(3-phenylthioureido)butyl]phosphonate and diphenyl [2-methyl-1-(3-phenylthioureido)butyl]phosphonate, both C(24)H(27)N(2)O(3)PS, are reported. In both compounds, the thiourea moiety adopts a syn-syn conformation (i.e. the S-C-N-C torsion angles are synperiplanar), which enables N-H...O hydrogen bonds to be formed between centrosymmetrically related molecules. The geometries around the P atoms can be described as distorted tetrahedral. Some of the functional groups in each structure are disordered. The bulk of the different alkyl substituents between the amide and phosphonate groups influences the molecular conformation and crystal packing. Although the structures of these compounds and two related derivatives appear to be similar, they are not isostructural.

9.
J Chromatogr A ; 947(1): 129-41, 2002 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11873992

RESUMO

A novel approach for the simultaneous analysis of glyphosate (PMG), and aminomethylphosphonic (AMPA, GlyP), N-methylaminomethylphosphonic (MAMPA. SarP) and methylphosphonic (MPA) acids is presented. This includes a preliminary 31P NMR analysis of mixtures of PMG, MPA, AMPA and MAMPA, their further derivatization to volatile phosphonates by means of the trifluoroacetic acid-trifluoroacetic anhydride-trimethyl orthoacetate reagent and subsequent MS [chemical ionization (CI) MS, GC-CI-MS, GC-electron impact ionization MS] and/or GC-flame ionization detection (FID) analysis of the products of derivatization. The detection limits of PMG, AMPA, MAMPA and MPA by means of GC-CI-MS and GC-FID were determined. The calibration graphs (GC-FID) for these derivatives were in the range 0.1 to 100 nmol linear and sufficiently reproducible for quantitative determinations. The applicability of the method was demonstrated during the analysis of water samples fortified with PMG, AMPA and MAMPA, characterized by recoveries of >95%.


Assuntos
Glicina/análogos & derivados , Glicina/análise , Herbicidas/análise , Calibragem , Cromatografia Gasosa/métodos , Espectrometria de Massas/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Glifosato
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