A novel homologous series a-4-[4'-n-alkoxy benzoyloxyj benzoyl-ß-3",4"-dimethoxy phenyl ethylenes has been synthesized and studied for liquid crystal (LC) properties to understand and establish the relation between molecular structure and liquid crystalline behavior Twelve members of series were synthesized. All the members except first member of the series are mesomorphic. The hexyloxy to tetradecyloxy homologoues are smectogenic and nematogenic in character. The ethoxy to pentyloxy and the hexadecyloxy homologues exhibit only nematogenic character with the absence of smectogenic mesophase formation. An odd-even effect is observed for the smecticnematic and the nematic-isotropic transition curves in the phase diagram. The smectic mesophase showed as either the SmA or SmC. The nematic mesophase shows a threaded or Schlieren type texture. Spectral and analytical data confirms the molecular structures of the homologues. The thermal stabilities for the smectic and the nematic are 115.6°C and 156.6°C. The smectogenic and nematogenic mesophase length va,y from 7°C to 28°C and from 7°C to 52^C respectively. The transition temperatures were observed through an optical polarizing microscope equipped with heating stage. Thus, the presently investigated novel homologous series is predominantly nematogenic and partly smectogenic with a middle ordered melting type and a considerable mesophase length. The LC properties of the novel series are compared with structurally similar homologous series.

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The present study evaluates the efficacy of ethanolic extract of Boerhaavia diffusa L (BD) administered orally at a dose of 500mg/kg body weight for a period of 30 days to alloxanized diabetic rats and its efficacy compared with the standard hypoglycaemic drug metformin. Diabetic animals showed glycemic dysregulation, altered ionic balance, increased levels of serum markers of kidney function, and reduced Na+-K+ ATPase activity and endogenous antioxidant status. Administration of BD not only maintained the ionic balance and renal Na+-K+ ATPase activity but also significantly minimized diabetic hyperglycaemia. The renal antioxidant status (GPx, Catalase, SOD and GSH) remained in the near normal range and LPO level lower than the non-diabetic level. These effects are comparable to the changes brought about by metformin treatment and even better. Over all, the present study provides evidence for BD to be a potent renoprotective and antihyperglycaemic agent in diabetic animals.

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A novel homologous series of liquid crystalline 4-(4 -n-alkoxy cinnamoyloxy)-4 -methoxy benzyl cinnamates was synthesized and studied with a view to understand and establish the effects of molecular structure on liquid crystal behavior. The series consists of eleven members of the series. None of the homologue derivatives are either nonliquid crystal or smectogenic, i.e. all the eleven members of the novel homologous series are enantiotropcially nematogenic only. Transition and melting temperatures as well as textures of the nematic mesophase were determined on an optical polarizing microscope equipped with a heating stage. The transition curves of the phase diagram show phase behavior in a normal expected manner. An odd-even effect is observed for the nematic-isotropic transition curve. The textures of the nematic mesophase are threaded or Schlieren as determined a by miscibility method. Analytical and spectral data confirm the molecular structures of the homologues. The average thermal stability for nematic is 213.8 • C. The isotropic temperatures vary between 190 • C and 240 • C. The nematogenic mesophase length varies from 17 • C to 102 • C. Thus, the novel homologous series is entirely nematogenic without the exhibition of smectogenic character. The liquid crystal (LC) properties of the present novel series are compared with structurally similar other known homologous series.

A novel homologous series α-4-[4 -n-Alkoxy benzoyloxy] benzoyl β-4 -methoxy phenyl ethylenes of 12 homologue substances is presented and comprises of 5 compounds (heptyl to tetradecyl) that exhibit both a smectic and a nematic phases. The pentyl, hexyl, and hexadecyl homologues only exhibit the nematic without exhibition of any smectogenic property. The methyl to butyl homologues are not liquid crystalline. All novel liquid crystal (LC) substances of novel series are enantiotropically mesomorphic. The textures of nematogenic homologues are threaded or Schlieren and that of the smectogenic homologues are typical of the smectic A or C. Analytical and spectral data support the molecular structures. Solid-mesomorphic or isotropic, Sm-N, and N-isotropic transition curves of a phase diagram behave in a normal manner. An odd-even effect is exhibited by the Sm-N and N-isotropic transition curves. Thermal stabilities for the smectic and nematic mesophases are 118.0 • C and 157.0 • C, respectively. The Sm-N mesophase length is between 13 • C and 21 • C, whereas the N-I mesophase length varies between 20 • C and 46 • C. The liquid crystal properties of the novel series are compared with known structurally similar homologous series.

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