Autori: Tokes, B, Ferencz, L, Szakacs, J, Kelemen, L, Darko, B

Editorial: 2nd Retrometabolism Based Drug Design and Targeting Conference, University of Florida, May 11-14, 1999., p.30, 1999.

Rezumat:

We have outlined some possibilities of retrometabolic drug design concept in phytobiochemistry and phytophysiology. In this respect, the research of phytohormones, namely auxins, is particularly remarkable. These growth stimulants, having effect both on genetic and metabolic levels, are at the same time in the central field of the up-to-date phytophysiological researches. Their action mechanism is disputed in several details, although it has been thoroughly studied. Experimentally it is known, that their growth stimulating activity as a function of the concentration passes over a maximum (optimum). This phenomenon agrees both with their selfregulating activity, i.e. the plant induces increasingly with its age the formation of decomposing enzymes (e.g. auxin-oxydases), and with the „two-point” theory of the action mechanism. It is obvious, that these interpretations, though they refer to the same result, differ essentially from one other. The oxidative mechanism probably produces formation of phytotoxic free radicals. In the retrometabolic drug design concept, it seems interesting to compare with that of the widespread 3-indole-butyric acid, as the hard lead compound. The soft analogs were synthesized by replacing the -CH2CH2- structural unit with the isosteric/isoelectronic -OCO- and -COO- groups (ester and reversed ester functions). The corresponding actions were studied by measuring the growth of the etiolated oat coleoptiles, as a concentration function. Several hundred statistically discussed data, as well as the comparison of the representative curves shows that the growth stimulant actions of soft analogs are comparable with of the hard one, and with the effect of indole-acetic acid. The decrease-rate of their activity at high concentrations is essentially smaller in the case of soft analogs, than of the lead compound. These results offer supplementary information regarding the action mechanism of phytohormones.

Cuvinte cheie: retrometabolism, fitobiochimie, fitohormoni // retrometabolism, phytobiochemistry, phytohormones

Autori: Tokes, B, Ferencz, L, Szakacs, J, Kelemen, L, Darko, B

Editorial: Pharmazie, 55, (3), p.243-244, 2000.

Rezumat:

We have outlined some possibilities of retrometabolic drug design concept in phytobiochemistry and phytophysiology. In this respect, the research of phytohormones, namely auxins, is particularly remarkable. These growth stimulants, having effect both on genetic and metabolic levels, are at the same time in the central field of the up-to-date phytophysiological researches. Their action mechanism is disputed in several details, although it has been thoroughly studied. Experimentally it is known, that their growth stimulating activity as a function of the concentration passes over a maximum (optimum). This phenomenon agrees both with their selfregulating activity, i.e. the plant induces increasingly with its age the formation of decomposing enzymes (e.g. auxin-oxydases), and with the „two-point” theory of the action mechanism. It is obvious, that these interpretations, though they refer to the same result, differ essentially from one other. The oxidative mechanism probably produces formation of phytotoxic free radicals. In the retrometabolic drug design concept, it seems interesting to compare with that of the widespread 3-indole-butyric acid, as the hard lead compound. The soft analogs were synthesized by replacing the -CH2CH2- structural unit with the isosteric/isoelectronic -OCO- and -COO- groups (ester and reversed ester functions). The corresponding actions were studied by measuring the growth of the etiolated oat coleoptiles, as a concentration function. Several hundred statistically discussed data, as well as the comparison of the representative curves shows that the growth stimulant actions of soft analogs are comparable with of the hard one, and with the effect of indole-acetic acid. The decrease-rate of their activity at high concentrations is essentially smaller in the case of soft analogs, than of the lead compound. These results offer supplementary information regarding the action mechanism of phytohormones.

Cuvinte cheie: fitobiochimie, retrometabolism, fitohormoni, auxine // phytobiochemistry, retrometabolism, phytohormones, auxine