Disclosed herein are a novel crown ether with bulky and rigid groups and a method for preparing the same. Also provided are a lithium adsorbent comprising the novel crown ether immobilized onto a nanofiber, and a method for preparing the same. The lithium-selective crown ether is synthesized through intermolecular cyclization between a bulky epoxide and a rigid aromatic compound such as 1,2-dihydroxybenzene, and can effectively recover lithium ions. For use as a lithium adsorbent, the novel crown ether with both bulky and rigid subunits is immobilized onto a polymer nanofiber. The crown ether-immobilized polymer nanofibers may be formed into a recyclable membrane.

Disclosed herein are a novel crown ether with bulky and rigid groups and a method for preparing the same. Also provided are a lithium adsorbent comprising the novel crown ether immobilized onto a nanofiber, and a method for preparing the same. The lithium-selective crown ether is synthesized through intermolecular cyclization between a bulky epoxide and a rigid aromatic compound such as 1,2-dihydroxybenzene, and can effectively recover lithium ions. For use as a lithium adsorbent, the novel crown ether with both bulky and rigid subunits is immobilized onto a polymer nanofiber. The crown ether-immobilized polymer nanofibers may be formed into a recyclable membrane.

The present invention relates to a condensed heterocyclic compound that has an enteropeptidase inhibitory effect and is useful in the treatment or prevention of obesity, diabetes mellitus, or the like, and a medicament containing the same. Specifically, the present invention relates to a compound represented by the following formula (I) or a salt thereof, and a medicament containing the same [in the formula, each symbol is as defined in the specification].

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The present invention relates to a condensed heterocyclic compound that has an enteropeptidase inhibitory effect and is useful in the treatment or prevention of obesity, diabetes mellitus, or the like, and a medicament containing the same. Specifically, the present invention relates to a compound represented by the following formula (I) or a salt thereof, and a medicament containing the same [in the formula, each symbol is as defined in the specification].

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Disclosed are ion-sensitive polymers and methods for their use for monitoring biological phenomena associated with ion fluxes, as well as organic electrochemical transistors including such polymers.

Disclosed are ion-sensitive polymers and methods for their use for monitoring biological phenomena associated with ion fluxes, as well as organic electrochemical transistors including such polymers.

1. The present invention relates to a method for the purification of halogenated oligosilanes as a pure compound or mixture of compounds each having at least one direct Si—Si bond, the substituents thereof being exclusively halogen or halogen and hydrogen, and the composition thereof being an atom ratio of substituent:silicon of at least 3:2, by the action of at least one purification agent on the halogenated oligosilane and isolation of the halogenated oligosilane with improved purity.

2.1. In the prior art, halogenated monosilanes such as HSiCl.sub.3 are purified by treatment with preferably polymeric organic compounds containing amino groups, and are separated out from these mixtures. This method cannot be used for halogenated oligosilanes because of the contained amino groups, since secondary reactions would lead to decomposition of the products. The new method should provide the desired products in high yield and purity without amino groups being used.

2.2. The purification of the halogenated oligosilanes is carried out in the presence of special purification agents, which convert contaminations such as, for example, FeCl.sub.2 into an insoluble and/or less volatile form. A separation of the products of completes the purification This method gives a high yield and avoids the problems associated with the prior art, such as, for example, long distillation times.

2.3. The method is suitable for the purification of, for example, Si.sub.2Cl.sub.6, Si.sub.3Cl.sub.8, Si.sub.4Cl.sub.10, and higher homologs. These find application, for example, in the deposition of silicon nitride layers in CVD processes.

1. The present invention relates to a method for the purification of halogenated oligosilanes as a pure compound or mixture of compounds each having at least one direct Si—Si bond, the substituents thereof being exclusively halogen or halogen and hydrogen, and the composition thereof being an atom ratio of substituent:silicon of at least 3:2, by the action of at least one purification agent on the halogenated oligosilane and isolation of the halogenated oligosilane with improved purity.

2.1. In the prior art, halogenated monosilanes such as HSiCl.sub.3 are purified by treatment with preferably polymeric organic compounds containing amino groups, and are separated out from these mixtures. This method cannot be used for halogenated oligosilanes because of the contained amino groups, since secondary reactions would lead to decomposition of the products. The new method should provide the desired products in high yield and purity without amino groups being used.

2.2. The purification of the halogenated oligosilanes is carried out in the presence of special purification agents, which convert contaminations such as, for example, FeCl.sub.2 into an insoluble and/or less volatile form. A separation of the products of completes the purification This method gives a high yield and avoids the problems associated with the prior art, such as, for example, long distillation times.

2.3. The method is suitable for the purification of, for example, Si.sub.2Cl.sub.6, Si.sub.3Cl.sub.8, Si.sub.4Cl.sub.10, and higher homologs. These find application, for example, in the deposition of silicon nitride layers in CVD processes.

Disclosed are cationic lipids which are compounds of Formula I. Cationic lipids provided herein can be useful for delivery and expression of mRNA and encoded protein, e.g., as a component of liposomal delivery vehicle, and accordingly can be useful for treating various diseases, disorders and conditions, such as those associated with deficiency of one or more proteins.

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A receptor for the simultaneous removal of oxoanions and their counterions from aqueous phase, particularly containing radioactive wastes, containing amide groups specifically coordinating the oxoanions, as well as moieties specifically coordinating cations, according to the present invention is characterised in that it contains within one molecule domains binding oxoanions and domains binding cations, preferably adapting a molecular structure of a general formula: (I) wherein Z this is a group containing crown ether, preferably a benzocrown group, X is any substituent, including the Y-Z grouping, and Y is any substituent or 0 (i.e. a direct bond between N and Z), where the oxoanion binding domain is a squaramide unit coordinating the oxoanions through amide groups, and squaramide contains additional substituents that increase or decrease the acidity of its amide protons, compared to unsubstituted squaramide, whereas the counter ion binding domain is a crown ether of a size adjusted to the type of binding cation, which forms part of at least one of the aforementioned substituents of squaramide, where the receptor has the ability to remove oxoanions and their counterions from aqueous phase to another water-immiscible phase, preferably to organic phase, and has the ability to form soluble complexes in at least one of the aforementioned phases. The invention considers also a method of removing oxoanions in the form of inorganic salts from aqueous phase, using receptors of the invention in the form of organic molecules containing amide groups, according to the invention is characterised in that it uses the aforementioned receptors for simultaneous binding of oxoanions and their counterions in aqueous phase, preferably acidic when using the receptor with substituents increasing acidity of squaramide protons, or alkaline when using the receptor with substituents decreasing acidity of squaramide protons. A sensor for detecting oxoanions according to the invention is characterised in that it uses the aforementioned receptors, dissolved or suspended in an organic solvent or in a mixture of organic solvents, forming coloured complexes in contact with the phase containing given oxoanions. The preparation for removing oxoanions from aqueous solutions, particularly containing radioactive waste at the stage preceding their disposal by vitrification, is characterised in that it contains the receptor according to the invention, dissolved or suspended in the water-immiscible phase, and the appropriate amount of counterion facilitating extraction. A process of utilisation of aqueous solutions by vitrification, particularly solutions containing radioactive waste, is characte