Compounds that are central nervous system drug candidates for the treatment of cognitive decline and, more particularly, Alzheimer's disease are provided. Methods of treating, inhibiting, and/or abatement of cognitive decline and/or Alzheimer's disease with a compound or pharmaceutically acceptable salt of the invention are also provided. Also provided are methods of preparing the compounds/compositions of the invention.

Compounds that are central nervous system drug candidates for the treatment of cognitive decline and, more particularly, Alzheimer's disease are provided. Methods of treating, inhibiting, and/or abatement of cognitive decline and/or Alzheimer's disease with a compound or pharmaceutically acceptable salt of the invention are also provided. Also provided are methods of preparing the compounds/compositions of the invention.

A method for synthesizing 2-(1-cyclohexenyl)ethylamine. Cyclohexanone (II) is reacted with a Grignard reagent in a first organic solvent to produce 1-vinylcyclohexanol (III), which is then subjected to chlorination and rearrangement reaction with a chlorinating reagent in a second organic solvent in the presence of an organic base to synthesize (2-chloroethylmethylene)cyclolxane (IV). Then (2-chloroethylmethylene)cyclohexane (IV) and urotropine are subjected to quaternization in a third organic solvent to synthesize N-cyclohexylidene ethyl urotropine hydrochloride (V). Finally, the N-cyclohexylidene ethyl urotropine hydrochloride (V) undergoes hydrolysis and rearrangement reaction in a solvent in the presence of an inorganic mineral acid to synthesize 2-(1-cyclohexenyl)ethylamine (I).

A method for synthesizing 2-(1-cyclohexenyl)ethylamine. Cyclohexanone (II) is reacted with a Grignard reagent in a first organic solvent to produce 1-vinylcyclohexanol (III), which is then subjected to chlorination and rearrangement reaction with a chlorinating reagent in a second organic solvent in the presence of an organic base to synthesize (2-chloroethylmethylene)cyclolxane (IV). Then (2-chloroethylmethylene)cyclohexane (IV) and urotropine are subjected to quaternization in a third organic solvent to synthesize N-cyclohexylidene ethyl urotropine hydrochloride (V). Finally, the N-cyclohexylidene ethyl urotropine hydrochloride (V) undergoes hydrolysis and rearrangement reaction in a solvent in the presence of an inorganic mineral acid to synthesize 2-(1-cyclohexenyl)ethylamine (I).

A method for synthesizing 2-(1-cyclohexenyl)ethylamine. Cyclohexanone (II) is reacted with a Grignard reagent in a first organic solvent to produce 1-vinylcyclohexanol (III), which is then subjected to chlorination and rearrangement reaction with a chlorinating reagent in a second organic solvent in the presence of an organic base to synthesize (2-chloroethylmethylene)cyclolxane (IV). Then (2-chloroethylmethylene)cyclohexane (IV) and urotropine are subjected to quaternization in a third organic solvent to synthesize N-cyclohexylidene ethyl urotropine hydrochloride (V). Finally, the N-cyclohexylidene ethyl urotropine hydrochloride (V) undergoes hydrolysis and rearrangement reaction in a solvent in the presence of an inorganic mineral acid to synthesize 2-(1-cyclohexenyl)ethylamine (I).

A method for synthesizing 2-(1-cyclohexenyl)ethylamine. Cyclohexanone (II) is reacted with a Grignard reagent in a first organic solvent to produce 1-vinylcyclohexanol (III), which is then subjected to chlorination and rearrangement reaction with a chlorinating reagent in a second organic solvent in the presence of an organic base to synthesize (2-chloroethylmethylene)cyclolxane (IV). Then (2-chloroethylmethylene)cyclohexane (IV) and urotropine are subjected to quaternization in a third organic solvent to synthesize N-cyclohexylidene ethyl urotropine hydrochloride (V). Finally, the N-cyclohexylidene ethyl urotropine hydrochloride (V) undergoes hydrolysis and rearrangement reaction in a solvent in the presence of an inorganic mineral acid to synthesize 2-(1-cyclohexenyl)ethylamine (I).

A diamine compound represented by H.sub.2NH.sub.2C-Ro.sup.2-CH.sub.2NH.sub.2, wherein Ro.sup.2 represents a residue of a resin acid dimer.

A diamine compound represented by H.sub.2NH.sub.2C-Ro.sup.2-CH.sub.2NH.sub.2, wherein Ro.sup.2 represents a residue of a resin acid dimer.

Compounds of formula (I), wherein the substituents are as defined in claim 1, and the agrochemically acceptable salts, stereoisomers, enantiomers, tautomers and N-oxides of those compounds, can be used as insecticides and can be prepared in a manner known per se. ##STR00001##

The present invention provides iron phosphide nanoparticles in which iron atoms are in a low valence state and which are stable under an atmospheric condition, a production method therefor, and a reduction catalyst. The present invention relates to iron phosphide nanoparticles having peaks at diffraction angles (20.5) of 48.3 and 32.7 in a powder X-ray diffraction measurement using CuK radiation, wherein, when the iron phosphide nanoparticles are measured by X-ray photoelectron spectroscopy (XPS), iron atoms contained therein have a peak in a range of 706.0 to 707.5 eV in an Fe2p.sub.3/2 spectrum.