Oa. Fathalla et al., Synthesis of new uracil-5-sulphonamide-p-phenyl derivatives and their effect on Biomphalaria alexandrina snail's nucleoproteins, ARCH PH RES, 23(2), 2000, pp. 128-138
In continuation of the previous work (Fathalla, 1992) on the synthesis of s
ome heterocycles containing uracil moiety, we report herein the incorporati
on of uracil moiety into cyanopyridine thione, thiosemecarbazone, semicarba
zone, cyanopyridine, aminocyano pyridine, isoxazoline, pyrazoline, pyrimidi
ne, triazolo pyrimidine, pyran, selena and thiazole derivatives which might
modify their biological activities.
The biological studies revealed that the chemical compound III f showed hig
h molluscicdal activity than other compounds. The profile of the nucleoprot
ein extracted from chemically (compound IIIc, e, f and g) treated or UV-irr
adiated B. alexandrina snails did not show appreciable differences when com
pared to non-treated (native) snails by using SDS-PAGE, where no obvious qu
alitative or quantitative differences were observed. Immunization of experi
mental animals with the nucleoprotein extracted from native, chemically (co
mpound III f St g) treated or physically treated B. alexandrina snails indu
ced significant protection against challenge with normal S. mansoni cercari
ae, as compared to the non-immunized challenged control. As well as, a decr
ease in the number of granuloma formation and the size range of granuloma w
as also observed in immunized animals. It is concluded that, compounds III
f and g have a potent molluscicidal activity. They also induced chemical mo
dification comparable to that induced by physical treatment in the snail's
nucleoprotein, which could possibly be used in immunization against S. mans
oni infection.