An object of the present invention is to provide a bismaleimide (D-BMI) modified product in which an amino group of dimer diamine (DDA) is maleimidized, which has the good heat resistance, and has the sufficiently enhanced processability, and a method for producing the same. There are provided: <1> A bismaleimide (D-BMI) modified product in which an amino group of dimer diamine is maleimidized, the bismaleimide modified product having the following characteristics: 1) An acid value of the D-BMI modified product is 2 mg-KOH/g or less. 2) In .sup.1H-NMR, when quantitative comparison is performed using an integrated value (A) of a peak corresponding to a proton of a methylene group directly bound to a nitrogen atom of a maleimide group and an integrated value (B) of a peak corresponding to a vinyl proton of a maleimide group, A/B is 1.25 or more and 2.00 or less. <2> A method for producing D-BMI, the method including the following steps: 1) A step of preparing a crude D-BMI solution having an acid value of more than 2 mg-KOH/g. 2) A step of lowering an acid value of D-BMI to 2 mg-KOH/g or less by reacting an acid component in the solution with a carbodiimide compound. 3) A step of reacting the solution without a catalyst at 110 to 200 C. in a solvent.

An object of the present invention is to provide a bismaleimide (D-BMI) modified product in which an amino group of dimer diamine (DDA) is maleimidized, which has the good heat resistance, and has the sufficiently enhanced processability, and a method for producing the same. There are provided: <1> A bismaleimide (D-BMI) modified product in which an amino group of dimer diamine is maleimidized, the bismaleimide modified product having the following characteristics: 1) An acid value of the D-BMI modified product is 2 mg-KOH/g or less. 2) In .sup.1H-NMR, when quantitative comparison is performed using an integrated value (A) of a peak corresponding to a proton of a methylene group directly bound to a nitrogen atom of a maleimide group and an integrated value (B) of a peak corresponding to a vinyl proton of a maleimide group, A/B is 1.25 or more and 2.00 or less. <2> A method for producing D-BMI, the method including the following steps: 1) A step of preparing a crude D-BMI solution having an acid value of more than 2 mg-KOH/g. 2) A step of lowering an acid value of D-BMI to 2 mg-KOH/g or less by reacting an acid component in the solution with a carbodiimide compound. 3) A step of reacting the solution without a catalyst at 110 to 200 C. in a solvent.

The present invention relates to a method for purifying N-substituted maleimide. More specifically, the present invention, without performing a water washing process, enables to remove organic-acid-impurities which are difficult to remove through distillation because of having similar boiling points to the N-substituted maleimide compound by utilizing solubility of organic-acid-impurities in an organic solvent used in the preparing process of the maleimide compound, and thereby, without producing washing wastewater, ensuring removal efficiency of the organic-acid-impurities equal to or similar to an N-substituted maleimide compound subjected to a water washing process.

The present invention relates to a method for purifying N-substituted maleimide. More specifically, the present invention, without performing a water washing process, enables to remove organic-acid-impurities which are difficult to remove through distillation because of having similar boiling points to the N-substituted maleimide compound by utilizing solubility of organic-acid-impurities in an organic solvent used in the preparing process of the maleimide compound, and thereby, without producing washing wastewater, ensuring removal efficiency of the organic-acid-impurities equal to or similar to an N-substituted maleimide compound subjected to a water washing process.

Compounds having cytotoxic and/or anti-mitotic activity are disclosed. Methods associated with preparation and use of such compounds, as well as pharmaceutical compositions comprising such compounds, are also disclosed. Also disclosed are compositions having the structure: (T)-(L)-(D), wherein (T) is a targeting moiety, (L) is an optional linker, and (D) is a compound having cytotoxic and/or anti-mitotic activity.

A method of increasing a density of carboxylic acids on a surface of a carbon nanoparticle is disclosed. The method includes contacting an oxygen-containing functional group on a surface of a carbon nanoparticle with a reducing agent to provide a hydroxyl group; reacting the hydroxyl group with a diazoacetate ester in the presence of a transition metal catalyst to provide an ester, the diazoacetate ester having the structure wherein R is a C1-8 hydrocarbyl, preferably tert-butyl, methyl, ethyl, isopropyl, allyl, benzyl, pentafluorophenyl, or N-succinimidyl; and cleaving the ester to provide a carboxylic acid group. Surface-functionalized carbon nanoparticles made by the method are also disclosed.

A method of increasing a density of carboxylic acids on a surface of a carbon nanoparticle is disclosed. The method includes contacting an oxygen-containing functional group on a surface of a carbon nanoparticle with a reducing agent to provide a hydroxyl group; reacting the hydroxyl group with a diazoacetate ester in the presence of a transition metal catalyst to provide an ester, the diazoacetate ester having the structure wherein R is a C1-8 hydrocarbyl, preferably tert-butyl, methyl, ethyl, isopropyl, allyl, benzyl, pentafluorophenyl, or N-succinimidyl; and cleaving the ester to provide a carboxylic acid group. Surface-functionalized carbon nanoparticles made by the method are also disclosed.

Provide is a polar compound having high chemical stability, high capability of aligning liquid crystal molecules, high solubility in a liquid crystal composition, and a large voltage holding ratio when the compound is used in a liquid crystal display device. A compound represented by formula (1) is applied.

##STR00001##

For example, in formula (1), P.sup.1 is any one of formulas (1b) to (1i), Sp is a single bond, Z is COO, and A is 1,4-phenylene.

##STR00002##

Provide is a polar compound having high chemical stability, high capability of aligning liquid crystal molecules, high solubility in a liquid crystal composition, and a large voltage holding ratio when the compound is used in a liquid crystal display device. A compound represented by formula (1) is applied.

##STR00001##

For example, in formula (1), P.sup.1 is any one of formulas (1b) to (1i), Sp is a single bond, Z is COO, and A is 1,4-phenylene.

##STR00002##

The invention provides novel methods for preparing indolinobenzodiazepine dimer compounds and their synthetic precursors.