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This paper reports attempts to obtain (anti)ferroelectric switchable achiral banana-shaped molecules without Schiff 's base units. For this purpose we have synthesized novel V-shaped molecules consisting of rigid angular central units [1,3-disubstituted benzene, 2,7-disubstituted naphthalene, 1,3-diphenylbenzene, 2,6diphenylnitrobenzene, 2,6-diphenylpyridine, 1,3-bis(phenylethynyl )benzene, 1-phenyl-3-(phenylethynyl )benzene] connected via ester linkages to two rigid cores (1,4-disubstituted benzenes, biphenyls, 2-phenylpyrimidines, phenylbenzoates). Most compounds have rather high melting points. Only molecules with seven aromatic rings show liquid crystalline properties. Two-dimensional modulated smectic phases (rectangular columnar phases) were found for molecules with phenylbenzoate rigid units. Intercalated fluid smectic phases were detected for the corresponding 2-phenylpyrimidine derivatives. For the first time in the case of banana-shaped molecules a nematic phase was observed for a 2∞-nitro-m-terphenyl-4,4◊-diyl bisbenzoate. However, none of the synthesized compounds exhibit the typical texture of the (anti)ferroelectric switchable mesophases, known from the Schiff 's base derivatives. like mesogens. Up to now, all banana-shaped liquid crystals

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Two new banana-shaped mesogens have been prepared and their mesophases have been studied. As indicated by calorimetry and polarizing microscopy both compounds exhibit two smectic mesophases. The structure of these phases have been studied by X-ray methods and NMR measurements. The electrooptical properties are discussed on the base of the structural data.

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