G. Csik et al., BIOPHYSICAL AND BIOLOGICAL PROPERTIES OF NEWLY SYNTHESIZED DIOXINOCOUMARIN DERIVATIVES .1. DARK EFFECTS ON T7 PHAGE AND HELA-CELLS, Journal of photochemistry and photobiology.B, Biology, 19(2), 1993, pp. 119-124
Several dioxinocoumarin derivatives have been synthesized for photoche
motherapeutical purposes. The physicochemical properties of 3,4-benzo-
6,7-dioxinocoumarin and its biological activity in the dark were studi
ed with regard to future photobiological applications. It was found th
at molecular aggregates are formed in aqueous solution at a concentrat
ion higher than 10(-5) mol l-1. In the dark, 3,4-benzo-6,7-dioxinocoum
arin inactivates T7 phage and inhibits the growth of HeLa cells in a c
oncentration-dependent manner. The dark inactivation of T7 phage was q
uantitatively characterized. It was found to be higher than that of 8-
methoxypsoralen (8-MOP) and approximately equal to 4,6,4'-trimethylang
elicin (TMA). From the inactivation kinetics and the lack of a quenchi
ng effect of polynucleotides on the fluorescence emission of the drug,
it appears that, apart from the induction of DNA damage, other events
are implicated in T7 phage dark inactivation. These results are impor
tant for the interpretation of the photobiological effects of this typ
e of compound.