New derivatives from dehydrocrotonin (DHC, compound I), with the same anti-
ulcerogenic properties but less toxicity were synthesised by reducing the c
yclohexenone moiety of DHC with NaBH4 (compound II), by reducing the cycloh
exenone and lactone moieties with LiAlH4 (compound III) and by transforming
the lactone moiety into an amide (compound IV) using dimethylamine. The cy
totoxicity of these derivatives from DHC uas assayed on V79 fibroblast cell
line. Three independent endpoints for cytotoxicity were evaluated. namely,
the nucleic acid content (NAC), tetrazolium reduction (MTT) and neutral re
d uptake (NRU). IC50 values of 540 and 350 muM were obtained for compound I
I in the NRU and NAC tests, respectively. Compound III was less toxic than
the other DHC derivatives (IC50 = 1800 muM) on V79 cells based on NAC assay
. Compound IV showed an IC50 ranging from 350 to 600 muM based on the three
endpoints evaluated. The three compounds were less toxic on V79 cells than
DHC. DHC, compounds II, III and IV did not change the respiration rate of
Escherichia coli on the acute toxicity assay. (C) 2001 Elsevier Science Ire
land Ltd. All rights reserved.