Takeda Pharmaceutical Company Limited

Tadashi Umemoto

Shumpei Murata

Naoki Miyamoto

Kenichi Miyata

Shinichi Masada

Yoji Hayase

Provided is an oligonucleic acid analog which contains, as at least one structural unit thereof, a modified nucleic acid monomer compound which is a ring-open nucleoside having a cleaved carbon-carbon bond between the 2' and 3&#x2032; positions and a substituent hydroxymethyl group at the 4&#x2032; position. When used as siRNA, the oligonucleic acid analog exhibits superior biological stability and target gene expression inhibiting activity. The oligonucleic acid analog can be used in antisense methods, ribozyme methods, and decoy methods, etc., can be used as a nucleic acid aptamer, and can also be used as a nucleic acid probe or molecular beacon, etc., or in genetic diagnostics, etc.

Modified nucleic acid

There is a demand for a convenient production method of an NC type purine nucleoside. The present invention relates to a method of producing a purine nucleoside represented the formula (I') or a salt thereof, which comprising reacting a pyrimidine nucleoside represented by the formula (I) or a salt thereof with a purine nucleobase represented by the formula B&#x2032;H in the presence of a Lewis acid.

Growing community of inventors

Fujisawa, Japan

Tadashi Umemoto