The present invention relates to a novel hydroxamate derivatives, more specifically, to novel hydroxamate derivatives having inhibitory activity against Histone Deacetylase (HDAC), isomers thereof, pharmaceutically acceptable salts thereof, hydrates or solvates thereof, use for preparing pharmaceutical compositions, pharmaceutical compositions comprising the same, treatment method using said composition, and a preparing method of novel hydroxamate derivatives. The novel selective hydroxamate derivatives having inhibitory activity against Histone Deacetylase (HDAC) compositions can be used for treatment of inflammatory disease, rheumatoid arthritis, or degenerative disease.
