New gemini anionic surfactants were prepared from sodium salts of monoalkyl sulfosuccinate esters of ethylene glycol having variably long tails (C 12 , C 16 , C 18 ) and dichloroethane. The chemical structures of the prepared surfactants were confirmed using different spectroscopic techniques. The surfaces tension values of the synthesized surfactants were measured at 25°C individually or mixing at different molar fractions with ethoxylated alkylphenol. In all cases, mixed micellar aggregates were formed and critical micellar concentrations of binary mixtures containing different mole fractions of the surfactants were measured. The micellization processes of the individual and mixed surfactants were investigated. The effect of different alkyl chains of gemini anionic surfactants on properties of binary systems and molar ratio in the mixed aggregates were deduced. The critical micelle concentration of mixed surfactants shifted to lower values compared to those of the single surfactants. Effectiveness values increased with decreases in the mole fraction of gemini anionic surfactants. The negative values of interaction parameter (b) increased with increases in the chain length of anionic surfactants. The activity coefficient (f 1 , f 2 ) and total minimum surface area of mixed solution were calculated. Also, the gemini anionic surfactants prepared have moderate antimicrobial activity towards bacteria and not active towards fungi.

Transparent monolithic discs were obtained in presence of different surfactants: sodium dodecyl sulfate (SDS), ethanediyl-1,2-bis (dimethyldodecylammonium bromide (Gemini 12-2-12) or alkyl hydroxyethyl dimethyl ammonium chloride (HY). The use of surfactants has modified the morphology and porosity of the silica host matrix for better sensing properties. The entrapment of TB into silica matrix has shifted pK a value to more basic and less acidic. The presence of Gemini 12-2-12 and HY surfactants has shifted pK a value to more acidic, whereas SDS has shifted pK a to more basic in comparison with that of entrapped TB/silica.

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Abstract3-Acetyl-4-hydroxy substituted coumarins (II a-c ) were prepared. Their reactions with hydrazines in DMF gave the corresponding 4-hydroxy -(3-substituted pyrazolin-3-yl)coumarins (IV a-f ) via the intermediate hydrazone (III). Their reaction with hydroxylamine hydrochloride gave the corresponding isoxazol-3-yl coumarin (VI a-c ) and (VII a,b ) via the oxime intermediate (V). Reaction of II with aromatic aldehydes gave the corresponding chalcone derivatives (VIII a-k ) which were reacted with hydrazines and hydroxyl amine hydrochloride and gave (IX a ) and (X a-c ). Condensation of (II a-c ) with aromatic aldehydes, malononitrile in the presence ammonium acetate yielded the corresponding 3-cyano-4-aryl nictoinamido-6-ylcoumarin (XI a-f ). 4-Hydroxy comumarin(1 a-c ) on treatment with POCl 3 in DMF give the corresponding 4-Chloro-3-formyl coumarin (XII a-c ) which on treatment with sod azide gave the corresponding 4-azido-3-formyl coumarin (XIII a-c ). 4-chloro-3-formyl coumarine (XII )on treatment with hydrazine gave pyrazolo coumarin derivatives (XIV a-d ) and on treatment with hydroxylamine hydrochloride gave 4-chloro-3-aldo oxime coumarin derivatives (XV a,b ). On treatment of 4-azido-3-formyl coumarin with active methylene compounds such as malononitrile and ethyl cyanocetate derivatives gave (XVI a-d ) respectively.The antibacterial and antifungal activities of some compounds have been described.