Transformation kinetics of the 5'-chloro-5'-deoxy analogue of arabinosylcytosine.

5'-Chloro-5'-deoxy arabinosylcytosine (Cl-araC) is a more lipophilic analog of the clinically used drug--arabinosylcytosine (araC). The resistance toward the enzyme cytidine-deaminase action was described as an characteristic feature of this synthetic nucleoside. The kinetics of the Cl-araC transformation in acid and alkaline solutions was studied at various temperatures.

In vitro antileukemic activity and chemical transformation of the 5'-chloro-5'-deoxy derivative of cyclocytidine.

Hydrochloride of 5'-chloro-5'-deoxy-cyclocytidine (Cl-cC) is an analogue of cyclocytine hydrochloride (cC), a prodrug of the compound with the strong antileukemic activity arabinosylcytosine (araC). This paper is devoted to the study of its cytotoxic activity in vitro and to the effect of acid and alkaline conditions and temperature on its stability. Cl-cC inhibits not only the growth of L1210 leukemia cells in vitro and the DNA synthesis (IC50 = 0.

Study of the stability and the kinetics of hydrolysis on the new potential antiarrhythmic "substance H + B".

"Substance H + B", N-[2-(2-heptyloxyphenylcarbamoyloxy)-ethyl]-N- benzylpiperidine chloride (1) is a new potential antiarrhythmic, prepared by quarternization of the local anesthetic, antiarrhythmic and antimicrobial heptacaine, N-[2-(2-heptyloxyphenylcarbamoyloxy)-ethyl]-piperidine chloride. The content of the work was a study of the stability of 1 based on the short-time stability tests of aqueous solutions, the observation of long-time storing of the substance and study of the kinetics of hydrolysis in aqueous, ethanolic buffer solutions. The conclusions of the presented results are: 1 is stable in acidic and neutral media, the alkaline hydrolysis is faster from the start compared to the hydrolysis of heptacaine, but later obtains an equilibrium character.

Study of local anaesthetics. Part 93: A contribution to the study of OSAR in the group of derivatives of phenylcarbamic acid.

The present paper has been focussed on the study of quantitative relations between structure, physico-chemical properties and biological activity in the series of substances with potential local anaesthetic and beta-adrenolytic effectiveness from the group of phenylcarbamic acid derivatives. The study of the above-mentioned relations and their interpretation could contribute to the optimization of new potential medicaments.