11 research outputs found
Studies on the Spectra of Protoberberine Alkaloids. II. Absorption Spectrum of Jatrorrhizine
Measurements have been made on the visible and UV absorption
spectra of jatrorrhizine chloride in pure aqueous, methanol,
ethanol a nd propa nol solutions and in the p resence of various
concentrations of e ither hydrochloric acid or potass ium h ydroxid e.
In all the solutions, potassium hydroxide conside rably modifies
the absorption curves. The modifications b ecome manifest in the
disappearance of the absorption maximum and in the appearance
of new bathochromic shifted maxima. In these changes isobestic
points were noticed in the absorption curves. At very high potassium
hydroxide concentrations in ethanol and propanol solutions, the
absorption maximum disappears from the vis ible region of the
spectrum.
It has been suggested that the addition of potassium hydroxide
causes the formation of the quinonoidic form of jatrorrhizine. The
carbinolic form probably appears only in ethanol and propanol
solutions
Syntheses and Spectrophotometric Studies of Some New Aralkyl Pyridinium Oximes
Syntheses and some physical properties of seven aralkyl
pyridinium oximes, potential antidotes against organophosphorus
poisons and potential reagents for pentacyano compounds of iron,
are described and discussed. Their UV absorption spectra in water
and in water-dioxane solutions at different pH values have been
measured. The spectral changes with changing pH in aqueous
solutions are attributed to the dissociati.on of individual functional
groups of the compounds, and in water-dioxane mixtures they are
attributed to the polarities of the solvents. One equilibrium is
established in most of the compounds, however, in PhPA-4 and
PhOPA-4 two equilibria exist. The dissociation constants of all
compounds have been determined spectrophotometrically. The pK\u27s
of the compounds are discussed in terms of the structure of the
compounds. A spectrophotometric method for the determination
of the examined compounds is proposed
Tödliche Vergiftungen in Zagreb und Umgebung
Izvršena je analiza smrtnih slučajeva otrovanja na području grada Zagreba i njegove okolice za period od 1934. do 1967. godine, tj. od osnutka Instituta do 1967. godine. Rezultati analize prikazani su tabelarno po godinama. načinu otrovanja (nesretni slučajevi, samoubojstva i ubistva), grupama otrova. životnoj dobi smrtno otrovanih, spolu i profesiji. Podaci za ovu analizu dobiveni su uvidom u arhiv Instituta za sudsku medicinu i kriminalistiku Medicinskog fakulteta u ZagrebuEs wurde eine Analyse der Fälle tödlicher Vergiftungen auf dem Gebiet der Stadt Zagreb und ihrer Umgebung für den Zeitraum von 1934 bis 1967, d. h. vom Beginn der Arbeit des Instituts bis 1967, durchgeführt. Die Resultate der Analyse werden in Tabellen aufgezeigt. und zwar nach den Jahren des Geschehens, nach der Vergiftungsart (Unglücksfälle, Selbstmorde, Morde) nach Giftgruppen und ichlierslich entsprechend dem Alter, Geschlecht und Profession der tödlich Vergifteten. Die Daten für diese Analyse wurden aus dem Archiv des Instituts entnommen
The UV and VIS Absorption Spectra of Jatrorubine
The absorption spectra of water, methanolic, ethanolic and
propanolic solutions of jatrorubine in the VIS and UV spectral
range were recorded. The acidity and the alkalinity of the solutions
were changed in the wide range from pH = 2 to pH = 13 by
the addition of KOH and HCl in the solutions. From the influence
of pH on the shapes of the absorption curves, it was concluded
that jatrorubine exists as quaternary aminic cation in the acidic
medium and as the resonance dipole molecula in the basic media,
but no evidence for the existence of carbinolic form was found.
The results were compared with the literature data
Studies on the spectra of protoberberine alkaloids. I. Absorption spectrum of Berberine
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