This work contains synthesis and characterization of new compounds [I-VIII], starting from compound [I] which was prepared through the reaction of chloroacetyl chloride with hydrazine hydrate and then cyclized the product with chloroacetic acid using phosphorous oxychloride to give 2,5-bis(chloromethyl)-1,3,4-oxadiazole compound [II], then the later compound [II] reacted with 4-hydroxy benzaldehyde to form compound [III]. The compound thiazolidine 2,4-dione [IV] was prepared from the reaction of chloroacetic acid with thiourea. Subsequently compound [III] reacted with compound [IV] to get [V] compound. Then the later compound was reacted with n-alkyl bromide (with several carbon atoms n= 4,5,6,8 ) to give compounds [VI]n. compound [VII] was prepared from the reaction of the compound [III] with mercaptoacetic acid and thiosemicarbazide, and then the product [VII] was reacted with 4 Ooctyloxybenzaldehyde to give compound [VIII]. The newly synthesized compounds were characterized by FTIR, 1HNMR and Mass spectrometry. The liquid crystalline properties were studied by polarizing optical microscopy(POM) and differential scanning calorimetry (DSC). All the compounds [VI]n displayed nematic phase only but compound [VIII] gave smectic B and nematic phase. Ii was found that the liquid crystalline properties of compounds[VI]n which include 1,3,4-oxadiazole as a core unit and thiazolidine-2,4-dione unite depending on the chain length of the alkyl group as terminal substituents.
