Abstract
Synthesis of new heterocyclic compounds containing four five-membered rings
together was the main goal of this work. The new derivatives of [tetrakis (1,2,4-
triazole /1,3,4-thiadiazole /1,3,4-oxadiazole][bis-(benzene-1,3,5-triyl)]
dioxymethylene A7-A18 were synthesized by the reaction of [bis-(dimethyl 5-ylisophthalate)]
dioxymethylene compound A1 which was previously prepared from
the reaction of 1,2-dibromomethan and dimethyl 5-hydroxyisophthalate, then treated
with hydrazine hydrate to yield the corresponding acid hydrazide A2. In the next
step, compound A2 was refluxed with 4-substituted isothiocyanate to give
substituted thiosemicarbazides A3-A6. The treatment of the latter compounds in
basic medium of 2M of NaOH afforded 1,2,4-Triazole derivatives A7-A10. Whereas
the reaction of the same compounds with concentrated sulfuric acid gave 1,3,4-
thiadiazoles A11-A14. Furthermore, the new derivatives of 1,3,4-oxadiazole A15-
A18 were obtained by the reaction of thiosemicarbazides and tosyl chloride in
presence of pyridine. (C. H. N.) elemental analysis, FT-IR, and 1HNMR techniques
were used to characterize the chemical structure of some of the new synthesized
compounds which also exhibited an important biological activity.
together was the main goal of this work. The new derivatives of [tetrakis (1,2,4-
triazole /1,3,4-thiadiazole /1,3,4-oxadiazole][bis-(benzene-1,3,5-triyl)]
dioxymethylene A7-A18 were synthesized by the reaction of [bis-(dimethyl 5-ylisophthalate)]
dioxymethylene compound A1 which was previously prepared from
the reaction of 1,2-dibromomethan and dimethyl 5-hydroxyisophthalate, then treated
with hydrazine hydrate to yield the corresponding acid hydrazide A2. In the next
step, compound A2 was refluxed with 4-substituted isothiocyanate to give
substituted thiosemicarbazides A3-A6. The treatment of the latter compounds in
basic medium of 2M of NaOH afforded 1,2,4-Triazole derivatives A7-A10. Whereas
the reaction of the same compounds with concentrated sulfuric acid gave 1,3,4-
thiadiazoles A11-A14. Furthermore, the new derivatives of 1,3,4-oxadiazole A15-
A18 were obtained by the reaction of thiosemicarbazides and tosyl chloride in
presence of pyridine. (C. H. N.) elemental analysis, FT-IR, and 1HNMR techniques
were used to characterize the chemical structure of some of the new synthesized
compounds which also exhibited an important biological activity.
Keywords
Dimethyl 5-hydroxyisophthalate
Dioxymethylene.
isothiocyanate
Triazole