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1
Content available remote Synteza chemiczna pochodnej 7-etylo-10-hydroksykamptotecyny
Kuang Hao, Wang Jisheng, Hong Zhiming, Li Haisong
Przemysł Chemiczny
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2024
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T. 103, nr 2
262--265
PL
Pochodna 7-etylo-10-hydroksykamptotecyny (I) została zsyntetyzowana z wysoką wydajnością (do 88%) przez substytucję nukleofilową przy użyciu glikolu etylenowego jako materiału wyjściowego. Grupę hydroksylową wprowadzono do struktury kamptotecyny (II) w pozycji C-10 przez substytucję nukleofilową, a glukozazydu użyto do następczej reakcji typu click.
EN
An 7-Et-10-hydroxycamptothecin (I) derivative was synthesized with a high yield (up to 88%) by nucleophilic substitution by using ethylene glycol as starting material. The OH group was introduced at the C-10 position of camptothecin structure through nucleophilic substitution and an glucose azide was used for the following click reaction.
2
Content available Polyester-camptothecin conjugates for controlled release
Sobczak M., Olędzka E., Kuras M., Luchowska U., Świniarska L., Wyrębiak R., Nałęcz-Jawecki G.
Engineering of Biomaterials
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2016
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Vol. 19, no. 138 spec. iss.
45
3
Content available Wstępne badania nad syntezą i charakterystyką wielkocząsteczkowych koniugatów kamptotecyny
Sobczak M., Olędzka E., Plichta A., Kolmas J., Piotrowska U.
Engineering of Biomaterials
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2014
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Vol. 17, no. 128-129
36--39
PL
Otrzymano nowe wielkocząsteczkowe koniugaty kamptotecyny. Matryce polimerowe zostały otrzymane w wyniku polimeryzacji z otwarciem pierścienia ε-kaprolaktonu, glikolidu, rac-laktydu oraz węglanu trimetylenu. Zsyntezowane matryce i kamptotecynę połączono za pomocą 1,6-diizocyjanianu heksametylenu. Otrzymane koniugaty wielkocząsteczkowe scharakteryzowano za pomocą spektroskopii 1H i 13C NMR oraz FTIR. Toksyczność otrzymanych produktów polimerycznych oceniono na podstawie testów przeprowadzonych przy użyciu bakterii luminescencyjnych oraz pierwotniaków. Ponadto, przeprowadzono badania kinetyki uwalniania kamptotecyny w warunkach in vitro.
EN
New macromolecular conjugates of camptothecin were prepared. The polymeric matrixes were obtained by the ring-opening polymerization of ε-caprolactone, glycolide, rac-lactide or trimethylene carbonate. The synthesized polymers and camptothecin were coupled via 1,6-hexamethylene diisocyanate. The synthesized macromolecular conjugates of camptothecin were characterized by 1H and 13C NMR or FTIR spectroscopy. Toxicity of the obtained polymeric products were evaluated with bacterial luminescence test and two protozoan assays. Furthermore, the in vitro release of camptothecin from the obtained conjugates was investigated.
4
Content available remote Affinity of new anticancer agent, 7-trimethylsilyl-ethyl-10-amino-camptothecin, to membranes and HSA determined by fluorescence spectroscopy methods
Kruszewski S., Kruszewska D. M.
Optica Applicata
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2008
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Vol. 38, nr 4
625-633
EN
The application of fluorescence anisotropy measurements in determining the properties of camptothecin analogue 7-trimethylsilylethyl-10-amino-camptothecin - a promising anticancer agent - is described in this paper. The fluorescence anisotropy measurements provide useful information about binding of camptothecins to membranes and proteins, including human serum albumin (HSA). Knowledge of these properties is important for potential clinical applications of these agents, and permits to select from camptothecin analogues only those which exhibit desirable properties. An active lactone form of camptothecin in fluids at pH 7.4 hydrolyses and converts into an inactive carboxylate form. The carboxylate form of camptothecin binds easily and irreversibly to HSA. Only free carboxylate form can transform back into lactone, then in the presence of HSA one direction transition occurs (from lactone to carboxylate); therefore in HSA solution, after about two hours, the lactone form almost totaly decays. On the other hand, the camptothecins bound to membranes do not hydrolyse. Fluorescence anisotropy measurements prove that 7-trimethylsilylethyl-10-amino-camptothecin exhibits desirable properties: high affinity of its lactone form to membranes and low affinity of its carboxylate form to HSA. Such properties should ensure high stability of this drug in physiological fluids, including blood.
5
Content available remote Deactivation rate of camptothecin determined by factor analysis of steady-state fluorescence and absorption spectra
Ziomkowska B., Kruszewski S., Siuda R., Cyrankiewicz M.
Optica Applicata
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2006
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Vol. 36, nr 1
137-146
EN
Camptothecin is a fluorescent compound exhibiting strong anticancer properties. A serious limitation to clinical application of this compound is its hydrolysis, when biologically active lactone form converts into inactive carboxylate. There are some differences in the shapes of both fluorescence and absorption spectra of the lactone and carboxylate forms of camptothecin. Therefore, during hydrolysis resultant fluorescence and absorption spectra evolve. Factor analysis of fluorescence/absorption spectra recorded during the hydrolysis process of camptothecin enables one to determine the temporary concentration of the lactone and carboxylate forms and obtain the deactivation rate of this compound.
6
Content available remote Affinity of new anticancer agent, DB-174, to membranes and HSA determined by fluorescence spectroscopy methods
Kruszewski S., Bom D., Ziomkowska B., Cyrankiewicz M.
Optica Applicata
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2006
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Vol. 36, nr 2-3
199-207
EN
The application of fluorescence spectroscopy methods to determining the properties of camptothecins promising anticancer agents are described in this paper. The fluorescence anisotropy measurements provide useful information about the binding of camptothecin and its analogues to cell membranes and human serum albumin (HSA) that is important for potential clinical applications of these agents, and permits the selection from many camptothecin analogues those ones exhibiting desirable biomedical properties. Binding properties of 7-trimethylsilyl-ethyl-10 hydroxy-camptothecin are the subject of this paper.
7
Content available remote Application of principal component and factor analysis of fluorescence spectra in camptothecin studies
Kruszewski S., Siuda R., Ziomkowska B., Cyrankiewicz M.
Optica Applicata
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2003
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Vol. 33, nr 2-3
369-380
EN
The application of fluorescence spectroscopy methods in investigations of camptothecin (CPT) is presented in this paper. Fluorescence of CPT enables one to follow the process of hydrolysis, i.e., the process of converting the biologically active lactone form into inactive carboxylate. The fluorescence spectra of CPT recorded during the hydrolysis were analysed using principal component analysis (PCA) and factor analysis (FA). The results obtained on the basis of fluorescence spectra analysis are compared with high performance liquid chromatography (HPLC) data.
8
Content available remote Zastosowanie metod fluorometrycznych do określania właściwości kamptotecyny i jej pochodnych
Kruszewski S.
Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna
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2003
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Vol. 9, nr 3-4
151-156
PL
Kamptotecyna (CPT) i jej pochodne stanowią ważną klasę S-fazowych przeciwnowotworowych związków. W warunkach fizjologicznych CPT szybko hydrolizuje i przechodzi w nieaktywną formę karboksylową. Zanik biologicznie aktywnej formy CPT jest szczególnie szybki w osoczu krwi. Analog kamptotecyny DB-67, w przeciwieństwie do CPT, wykazuje wyjątkowo dużą stabilność we krwi. Metody spektroskopii fluorescencyjnej zostały zastosowane do określania fizycznych i przewidywania biologicznych właściwości kamptotecyny i jej analogów.
EN
Camptothecin (CPT) and related congeners have became an important class of S-phase anticancer agent. Unfortunately CPT hydrolyses under physiological conditions, and converts into inactive carboxylate form. Decrease of active form of CPT occurs especially fast in plasma of human blood. The new camptothecin analogue DB-67, in contrary to CPT, exhibits impressive blood stability. Fluorescence spectroscopy methods were used to determine physical and to predict biological properties of camptothecins.
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