- Surface activities, foam properties, HLB, and krafft point of some n-alkanesulfonates (C14-C18) with different isomeric distributions
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A homologue series of sodium secondary n-alkanesulfonates (C14, C16 and C18) were obtained by photosulfochlorination process with two different reaction conditions. Different length chains with different isomeric distributions of n-alkanesulfonates are expected to present variations in physicochemical properties. In this investigation, the relationships between their isomeric distribution and their chain length and micellar behaviors were thoroughly explored. Their CMC at different temperatures were determined using specific conductivity and surface tension measurements. Through surface tension isotherms, the surface activities (γCMC) were obtained. The surface absorption amounts (Cmax) and the molecular areas (Amin) were calculated using Gibb's equation. As expected, these surfactants exhibit good surface properties. It was shown that the CMC values increase with increasing the percentage of secondary isomers, with a surface tension decrease. It was also shown that the CMC values decrease with increasing chain length. The HLB values were calculated for each surfactant and the results obtained suggest that they are O/W emulsifiers. The foam properties of synthesized surfactants were evaluated and compared to those obtained for commercial samples. It was shown that the foamability is influenced both by the length of the hydrophobic moiety and the percentage of secondary isomers. It can be easily concluded that the C14 sulfonates show the best foaming properties independently of their isomeric distribution. The Krafft point values obtained indicate that the micellization and the surfactant solubility mainly depend on the proportion of secondary isomers and the length of hydrophobic moiety. AOCS 2012.
- Fekarcha, Latifa,Tazerouti, Amel
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- Synthesis and Physicochemical Properties of Alanine-Based Surfactants
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The synthesis of a homologous series of alanine-based surfactants, namely sodium salts of n-alkanesulfonamido-2-propanoic acids in which n-alkane is n-dodecane, n-tetradecane, n–hexadecane, and n-octadecane having the formula RSO2NHCH (CH3)COO?Na+, is described. The starting materials used were a mixture of secondary positional isomers of n-alkanesulfonyl chlorides obtained by photosulfochlorination reaction using sulfuryl chloride and a catalyst. Surface properties of the aqueous solutions of the synthesized surfactants, including the critical micelle concentration and minimal surface tension δmin, were determined using surface tension measurements at 25?°C. The surface excess Γ and minimum area per molecule (Amin) where calculated using the Gibbs equation. The foaming power was also determined by the Bartsh method, and the R5 parameter was calculated to estimate the stability of the foam formed. The results obtained were compared to those of a commercial surfactant, sodium dodecylsulfate, and a series of synthesized glycine-based surfactants. The results obtained clearly show that the alanine-based surfactants possess good surface properties. The investigations highlight the influence on the surface properties of the addition of a methyl group in the hydrophilic part.
- Bougueroua,Mousli,Tazerouti
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p. 1121 - 1131
(2016/10/18)
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- Synthesis and some surface properties of glycine-based surfactants
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A new group of anionic surfactants, namely sodium salts of secondary alkanesulfonamidoacetic acid, were synthesized using n-alkanesulfonyl chlorides as starting materials. These surfactants, having the formula: R-SO 2-NH-CH2-COONa, with R = C12, C14, C16 and C18, were obtained in a simple way with quantitative yields. Different chain lengths and positional isomers of this new type of surfactants are expected to present differences in surface properties and foamability. The surface properties including critical micelle concentrations and minimal surface tensions γmin were determined for each prepared surfactant using surface tension measurements with a Wilhelmy plate. Surface excess and minimum area per molecule at the air-water interface were determined for different concentrations at 25 and 50 °C using the Gibbs equation. The foaming power was also determined by the Bartsch method, and the results obtained were compared to those of a commercial surfactant, the linear alkylbenzenesulfonate. The stability of the foam formed was also evaluated. As expected, these surfactants exhibit good surface properties and show good foaming power.
- Mousli, Radia,Tazerouti, Amel
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experimental part
p. 65 - 72
(2012/01/13)
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- HETEROCYCLIC COMPOUNDS CONTAINING NITROGEN ATOMS OR PHARMACEUTICALLY ACCEPTABLE SALTS THEREOF, PROCESS FOR THE PREPARATION THEREOF AND PHARMACEUTICAL COMPOSITION COMPRISING THE SAME FOR TREATMENT OF CANCER
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The present invention relates to new heterocyclic compounds containing nitrogen atoms or pharmaceutically acceptable salts thereof, a process for the preparation thereof, and a pharmaceutical composition comprising the same for treatment of cancer. The compounds according to the present invention induce DNA damage due to reactive oxygen species to activate c-abl and p53, induce RhoB to generate apoptosis, and induce cell death by down-regulating Bcl2 involved in cell survival, which is generated by dysregulated signals via the mitochondria pathway, thereby inhibiting tumor cell growth and inducing apoptosis. Accordingly, the composition according to the present invention can be used to treat cancer.
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Page/Page column 14
(2010/06/19)
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- NEW HETEROCYCLIC COMPOUNDS CONTAINING NITROGEN ATOMS OR PHARMACEUTICALLY ACCEPTABLE SALTS THEREOF, PROCESS FOR THE PREPARATION THEREOF AND PHARMACEUTICAL COMPOSITION COMPRISING THE SAME FOR TREATMENT OF CANCER
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The present invention relates to new heterocyclic compounds containing nitrogen atoms or pharmaceutically acceptable salts thereof, a process for the preparation thereof, and a phar? maceutical composition comprising the same for treatment of cancer. The compounds according to the present invention induce DNA damage due to reactive oxygen species to activate c-abl and p53, induce RhoB to generate apoptosis, and induce cell death by down-regulating Bcl2 involved in cell survival, which is generated by dysregulated signals via the mitochondria pathway, thereby inhibiting tumor cell growth and inducing apoptosis. Accordingly, the composition according to the present invention can be used to treat cancer.
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Page/Page column 19-20
(2008/06/13)
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