Original scientific paper

Studies on the Spectra of Protoberberine Alkaloids. I. Absorption Spectrum of Berberine

Z. Gašparec ; Institute of Pharmaceutical Chemistry, Facul ty of Pharmacy and Biochemistry, and Institute of Forensic Medicine, FacuLty of Medicine, University of Zagreb, Zagreb , Croatia, Yugoslavia
K. Weber ; Institute of Pharmaceutical Chemistry, Facul ty of Pharmacy and Biochemistry, and Institute of Forensic Medicine, FacuLty of Medicine, University of Zagreb, Zagreb , Croatia, Yugoslavia

Abstract

Measurements have been made of the visible and UV
absorption spectra of berberine chloride in pure aqueous, methanol,
ethanol and propanol solutions and in the presence of various
concentrations of either hydrochloric acid or potassium hydroxide.
In all solutions, potassium hydroxide considerably influences
both the form of the absorption curves and the values of the extinction
coefficients. Bathochromic shifts (red s hift s) of the ab sorption
maxima were observed in the ultra-violet spectrum and
the disappearence of the absorption maxima in the visible.
It has been suggested that the addition of potassium hydroxide
causes the formation of the carbinolic form of berberine in all but
the aqueous solutions. The open carbinol form is probably formed
in the presence of l arge concentrations of KOH. It was found that
the shapes of the absorption curves of berberine in the presence of
KOH differ widely in different solvents .

Keywords

Hrčak ID:

208155

URI

https://hrcak.srce.hr/208155

Publication date:

25.11.1966.

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