Oligonucleotide derivatives, a pharmaceutical composition for the treatment and diagnostic pharmaceutical composition comprising an oligonucleotide derivative, as well as miRNA function for suppressing oligonucleotide derivatives
Repeating oligonucleotide derivative represented by the following formulas (wherein, B represents adenine, guanine, cytosine or uracil, X represents a sulfur atom or an oxygen atom, n is representing. An integer of 6-60) represented by (In the formula, B and X,., represented independently in each of the repeating structural units) structural units consist, X at least one repeating structural unit represented by the general formula is a sulfur atom .オリゴヌクレオチド誘導体は、下記一般式（式中、Ｂはアデニン、グアニン、シトシン又はウラシルを表し、Ｘは硫黄原子又は酸素原子を表し、ｎは６～６０の整数を表す。）で表される繰り返し構成単位（前記一般式中、Ｂ及びＸは、それぞれの繰り返し構成単位において独立に表される。）からなり、前記一般式で表される繰り返し構成単位の少なくとも１つにおいてＸが硫黄原子である。
