16250-48-9

Upstream product

• 17343-93-0 1,10-Di(α-cyclohexanone)decane-1,10-dione 
• 111-19-3 sebacoyl chloride 
• 111-20-6 1,10-decanedioic acid 
• 505-56-6 docosanedioic acid 

Downstream Products

• 129577-57-7 1,20-bis(4-formylphenoxy)eicosane dicarboxylate 
• 1622913-90-9 bis{4-(4-chlorophenyl)-1-[4-(4-fluorophenyl)-4-oxobutyl]piperidin-4-yl} docosanedioate 
• 129577-56-6 (S)-bis(2-methylbutyl)-3,3'-<1,20-eicosanediylbisbis<2-propenoate>> 

Relevant academic research and scientific papers

Micelle-Mimetic Ionene Polyelectrolytes

The properties of a series of linear cationic polyelectrolytes of the -ionene type (dimethylammonium charge centers interconnected by alternating chain segments containing n and m CH2 groups, respectively) have been investigated in aqueous solution.Ionenes with short segments, i.e., the -ionene and the -ionenes with m -ionenes with m > 14 are quite distinct.Thus, increasing m beyond 14 results in a progressive increase in the net degree of bromide counterion association to the ionene (conductivity data), enhanced solubilization of hydrophobic substrates (pyrene) in a progressively less aqueous environment, a gradual increase in the fluorescence anisotropy of an ionene-adsorbed anionic fluorescein derivative, and an increase in the selctivity of chloride/bromide counterion exchange at the ionene surface.These m-dependent changes in solution properties, which correlate nicely with the m-dependent onset and rise of catalytic activity (acceleration of the rate of alkaline hydrolysis of p-nitrophenyl octanoate), are consistent with a change in ionene conformation, going from extended to progressively more compact (globular or micellelike) as the segment length m is increased beyond 14.Indeed, the observed effects of the -, -, and -ionenes on reaction rate can be quantitatively reproduced by using the pseudophase ion-exchange formalism originally developed for micellar systems.The marked similarity between the -ionene and the CTAB micelle with respect to counterion binding, counterion-exchange selectivity, substrate solubilization, and catalytic rate enhancement suggests that amphiphilic ionenes of this type should be excellent prototypes for the rational design of micelle-mimetic polyelectrolytes.

Ultrathin Monolayer Lipid Membranes from a New Family of Crown Ether-Based Bola-Amphiphiles

Twelve novel α,Ω-bis(N-azacrown ether) compounds have been prepared, characterized, and converted into a previously unknown type of niosome.Four are bis(15-crown-5) derivatives having the following spacer chains: (CH2)12 (1), (CH2)16 (2), CO(CH2)20CO (3), and (CH2)22 (4).The eight bis(aza-18-crown-6) derivatives have the following spacers: (CH2)10 (5), CO(CH2)10CO (6), (CH2)12 (7), CO(CH2)14CO (8), (CH2)16 (9), (CH2)22 (10), (CH2)12O(CH2)12 (11), and CO(CH2)11S(CH2)12S(CH2)11CO (12).Aggregation studies of 1 and 7, employing transmission electron microscopy as well as dynamic and static light scattering, demonstrate that these compounds form a novel class of spherical monolayer lipid membrane vesicles when dispersed in water.Debye light-scattering profiles obtained from a suspension of large (ca. 200 nm diameter) vesicles indicate a relative refractive index near 1.Dynamic turbidimetry in acidic media on a suspension of bola-amphisomes formed from 1, suggested that the contribution of micelle-vesicle equilibria to the bolyte aggregation state is negligible.In neutral or slightly alkaline pH at 35 deg C, the vesicles grew irreversibly to yield large, probably multilamellar, aggregates.In acidic media at pH 2, the bola-amphisomes do not coalesce, even at 65 deg C.On the basis of the observations presented here, bola-amphiphiles having a hydrocarbon span of 10-12 carbon atoms aggregate in aqueous media into vesicles.When the aliphatic backbone incorporates 16 or more carbon atoms, micelles are formed.

Analytical applications and implications of intramolecular micelle-mimetic ionene aggregates

The synthesis and relevant properties of some cationic polyelectrolytes of the [x,y]-ionene type (i.e., molecules consisting of dimethylammonium charge centers interconnected by alternating alkyl chain segments containing x and y methylene groups) are described. Such hydrophobic ionenes can form intramolecular aggregates and function as micelle-mimetic agents since they mimic the key properties of traditional surfactant micelles (such as hexadecyltrimethylammonium bromide) in many respects. However, the ionenes possess certain important advantages over surfactant micelles. For example, aqueous ionene-containing solutions exhibit much less foaming and analyte molecules can be extracted and recovered from their solutions by use of organic solvents. In this work, some applications of the ionenes in analytical chemistry, such as their use as mobile phase additives for thin-layer chromatographic and capillary electrophoretic separations, as fluorescence enhancement agents, and as a means to catalyze slow spectroscopic derivatization reactions are demonstrated. In addition, other potential advantages concerning the utilization of the micelle-mimetic ionenes in chemical analysis applications are mentioned.

Synthesis and binding profile of haloperidol-based bivalent ligands targeting dopamine D2-like receptors

Homodimers of dopamine D2-like receptors are suggested to be of particular importance in the pathophysiology of schizophrenia and, thus, serve as promising targets for the discovery of atypical antipsychotics. This study describes the development of a series of novel bivalent molecules with a pharmacophore derived from the dopamine receptor antagonist haloperidol. These dimers were investigated in comparison to their monomeric analogues for their D2long, D2short, D3, and D4 receptor binding and the ability to bridge two neighboring receptor protomers. Radioligand binding studies provided diagnostic insights when Hill slopes close to two for the bivalent ligand 13 incorporating 22 spacer atoms and a comparative analysis with monovalent control ligands indicated a bivalent binding mode with a simultaneous occupancy of two neighboring binding sites.

Chemical switching of vesicle bilayer membrane disruption by bis(crown ether) bolaamphiphiles

Bis(crown ether) bolaamphiphiles derived from 18-crown-6 dicarboxylic acid were prepared, and their ability to release vesicle encapsulated 5[6]- carboxyfluorescein was determined. Bolaamphiphiles with a linear central spacer are poor membrane disrupting agents except in the presence of alkaline earth metal cations or ethylenediammonium cation. Divalent ion enhancement of membrane disruption is cation selective and can be used to determine the apparent association constant of the bolaamphiphile crown ether with the added cation. The cis-isomer of a thioindigo bis(crown ether) bolaamphiphile is an active membrane disrupting agent, but the trans-isomer is significantly less active. In homogeneous solution, cis-to-trans thermal and photochemical isomerization is retarded by added alkaline earth metal salts, indicating that cooperative ditopic binding of the cations occurs despite the inherent flexibility of the bolaamphiphile. The membrane disruption mechanism occurs via U-shaped conformations of the bolaamphiphile. All available data indicate that divalent cations accelerate membrane disruption by stabilization of the U-shaped conformation via cooperative interaction of the crown ethers with the dication. Thus the membrane disruption process is switched 'on' by molecular recognition.

Design, synthesis, and activity of membrane-disrupting bolaphiles

Four new classes of bolaphiles ("double-headed" single-chain surfactants) have been prepared, via condensation of an homologous series of linear saturated, olefinic, and acetylenic α,ω-dicarboxylic acids with hexaethylene glycol, and evaluated for their ability to induce the release of 5(6)-carboxyfluorescein (CF) entrapped within large unilamellar vesicles derived from 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC). Operationally, the membrane-disrupting activity of the bolaphiles has been found to vary by a factor of ca. 100, when the total number of carbon atoms which separate the carboxylate moieties range from 12 to 24; the most active bolaphile is approximately three times more active than Triton X-100. When the affinity of the bolaphiles toward POPC membranes is considered, the intrinsic membrane-disrupting activity varies by a factor of ca. 230. A "loop" model is proposed to account for the general trends in bolaphile activity that are observed, where the depth of loop penetration and loop width are presumed to be the key factors involved in determining membrane-disrupting activity. The potential utility of these surfactants as antimicrobial agents, and as anti-HIV agents in particular, is briefly discussed.

INTRAMOLECULAR END-TO-END REACTIONS OF PHOTOACTIVE TERMINAL GROUPS LINKED BY POLYMETHYLENE CHAINS.

Intramolecular end-to-end reactions of a pair of photoactive terminal groups, dibenz left bracket b,f right bracket azepine (DBA) chromophores, linked by a series of polymethylene chains (DBA-CO(CH//2)//nCO-DBA, n equals 2-30) were studied by two different approaches. One approach is to measure the intramolecular deactivation rate constants of the excited triplet state of terminal DBA groups by the nanosecond laser photolysis and the other is to measure the intramolecular photocyclization rates of these bichromophoric compounds by the quantitative product analysis with GPC. The excited triplet state of the DBA group is the intermediate of the reaction.