Original scientific paper

FT-IR and NMR spectroscopic studies of salicylic acid derivatives. I. Gentisamide - a metabolite of salicylamide

MILENA JADRIJEVIĆ-MLADAR TAKAČ
DRAŽEN VIKIĆ TOPIĆ
TIHANA GOVORČINOVIĆ

Abstract

Gentisamide (GAM, 2,5-dihydroxybenzamide), a minor first-pass metabolite of salicylamide (SAM, 2-hydroxybenzamide), was studied using FT-IR, 1D and 2D homo- and heteronuclear 1H and 13C NMR spectroscopy.
GAM was isolated from human urine eight hours after oral administration of SAM. FT-IR, 1H and 13C NMR spectra unequivocally confirmed the chemical structure of GAM through chemical and substituent shifts, coupling constants and connectivities in COSY, NOESY, HETCOR and HBMC spectra.
From NOESY spectra of GAM in DMSO-d6, it was concluded that the amide protons are oriented toward the ortho-proton at C-6. Obtained results indicate that the presence of the additional phenol group at C-5 in GAM favours the formation of intramolecular hydrogen bonding of the O…HO type between C2-OH proton and oxygen atom of the amide group.

Keywords

gentisamide; NSAID; salicylamide; biotransformation; FT-IR; 1D and 2D homo- and heteronuclear 1H and 13C NMR

Hrčak ID:

16861

URI

https://hrcak.srce.hr/16861

Publication date:

1.9.2004.

Article data in other languages: croatian

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