Tautomeric transformations of piroxicam in solution: a combined experimental and theoretical study

D Ivanova; V  Deneva; D Nedeltcheva; Fadhil S. Kamounah; G Gergov; Poul Erik Hansen; S Kawauchi; L Antonov

doi:10.1039/c5ra03653d

Tautomeric transformations of piroxicam in solution: a combined experimental and theoretical study

D Ivanova, V Deneva, D Nedeltcheva, Fadhil S. Kamounah, G Gergov, Poul Erik Hansen, S Kawauchi, L Antonov

Kemi

Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › peer review

Abstract

Piroxicam tautomerism was studied in solution by using UV-Vis spectroscopy, NMR measurements and advanced chemometrics. It has been found that in ethanol and DMSO the enol-amide tautomer is present mainly as a sandwich type dimer. The addition of water leads to distortion of the aggregate and to gradual shift of the equilibrium towards the zwitterionic tautomer. Quantitative data for the aggregation and the tautomeric equilibria are presented. Quantum chemical calculations (M06-2X/TZVP) have been used to explain stability of the tautomers as a function of the solvent and concentration.

Originalsprog	Engelsk
Tidsskrift	RSC Advances
Vol/bind	5
Udgave nummer	40
Sider (fra-til)	31852-31860
Antal sider	9
ISSN	2046-2069
DOI	https://doi.org/10.1039/c5ra03653d
Status	Udgivet - 2015

Emneord

piroxicam

Link til dokument

10.1039/c5ra03653dLicens: CC BY

c5ra03653dForlagets udgivne version, 1,15 MBLicens: CC BY

Citer dette

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abstract = "Piroxicam tautomerism was studied in solution by using UV-Vis spectroscopy, NMR measurements and advanced chemometrics. It has been found that in ethanol and DMSO the enol-amide tautomer is present mainly as a sandwich type dimer. The addition of water leads to distortion of the aggregate and to gradual shift of the equilibrium towards the zwitterionic tautomer. Quantitative data for the aggregation and the tautomeric equilibria are presented. Quantum chemical calculations (M06-2X/TZVP) have been used to explain stability of the tautomers as a function of the solvent and concentration.",

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T1 - Tautomeric transformations of piroxicam in solution: a combined experimental and theoretical study

AU - Ivanova, D

AU - Deneva, V

AU - Nedeltcheva, D

AU - Kamounah, Fadhil S.

AU - Gergov, G

AU - Hansen, Poul Erik

AU - Kawauchi, S

AU - Antonov, L

PY - 2015

Y1 - 2015

N2 - Piroxicam tautomerism was studied in solution by using UV-Vis spectroscopy, NMR measurements and advanced chemometrics. It has been found that in ethanol and DMSO the enol-amide tautomer is present mainly as a sandwich type dimer. The addition of water leads to distortion of the aggregate and to gradual shift of the equilibrium towards the zwitterionic tautomer. Quantitative data for the aggregation and the tautomeric equilibria are presented. Quantum chemical calculations (M06-2X/TZVP) have been used to explain stability of the tautomers as a function of the solvent and concentration.

AB - Piroxicam tautomerism was studied in solution by using UV-Vis spectroscopy, NMR measurements and advanced chemometrics. It has been found that in ethanol and DMSO the enol-amide tautomer is present mainly as a sandwich type dimer. The addition of water leads to distortion of the aggregate and to gradual shift of the equilibrium towards the zwitterionic tautomer. Quantitative data for the aggregation and the tautomeric equilibria are presented. Quantum chemical calculations (M06-2X/TZVP) have been used to explain stability of the tautomers as a function of the solvent and concentration.

KW - piroxicam

KW - isotope effects

KW - NMR

KW - DFT calculations

KW - piroxicam

KW - dimer

U2 - 10.1039/c5ra03653d

DO - 10.1039/c5ra03653d

M3 - Journal article

SN - 2046-2069

VL - 5

SP - 31852

EP - 31860

JO - RSC Advances

JF - RSC Advances

IS - 40

ER -