NOVEL CYCLIC TETRAPEPTIDE DERIVATIVES AND MEDICINAL USE THEREOF

摘要

Cyclic tetrapeptide derivatives represented by general formula (I) or pharmaceutically acceptable salts thereof, cyclic tetrapeptide compounds analogous thereto, and histone deacetylase inhibitors, MHC class-1 molecule expression promoters and medicinal compositions containing these cyclic tetrapeptide derivatives as the active ingredient: wherein R11, R12, R21 and R22 represent each hydrogen or a monovalent group selected from linear or branched C1-6 alkyl, benzyl, 4-methoxybenzyl, 3-indolylmethyl, (N-methoxy-3-indolyl)methyl, (N-formyl-3-indolyl)methyl, etc.; R3 represents a divalent group selected from divalent linear C3-4 hydrocarbyl optionally having a branched chain added thereto or optionally substituted by a heteroatom; and R4 represents a divalent group derived from divalent linear C4-6 hydrocarbyl optionally having a branched chain added thereto.