A GERMINATION BIOASSAY AS A TOXICOLOGICAL SCREENING SYSTEM FOR STUDYING THE EFFECTS OF POTENTIAL PRODRUGS OF NAPROXEN

A germination bioassay with radish (Raphanus sativus L.) seeds was dev eloped as a toxicological screening system for assessing the effects o f new potential prodrugs of naproxen, as an alternative to animals and animal cell toxicity screens. Both enantiomers of naproxen (6-methoxy -alpha-methyl-2-naphthaleneacetic acid) and naproxol (6-methoxy-beta-2 -naphthaleneethanol), and their racemic mixtures, inhibited the radicl e growth of R. sativus at a concentration of 1mM, while only (R)-(+)-n aproxol and racemic naproxol inhibited the hypocotyl growth of R. sati vus at the same concentration. Four novel combinatorial esters, naprox en naproxyl esters (6-methoxy-beta-methyl-2-naphthaleneethyl 6-methoxy -alpha-methyl-2-naphthaleneacetate), resulting from the combinatorial chemistry of the esterification reaction between naproxen and naproxol , were synthesised and then tested in the germination bioassay, at a c oncentration of 0.5mM. It was found that they did not inhibit either t he radicle or the hypocotyl growth of R. sativus.