PURPOSE: To obtain a new thionucleoside which is expected to be developed as a carcinostatic agent because it is a 2'-deoxy-2',2'-dihalogeno-4'-thionucleoside having a specific substituent introduced in the 2'-position of the saccharide moiety and has excellent antitumor action.
CONSTITUTION: A new 2'-deoxy-2',2'-dihalogeno-4'-thionucleoside which is represented by formula I (B is pyrimidine base or purine base; R1, R2 are each a halogen; R3 is H, an acyl, phosphoric acid residue), for example, 2'-deoxy-2',2'- difluoro-4'-thiocytidine and has antitumor action, thus can be expected to be developed as a carcinostatic agent. This compound is obtained by sulfonylating hydroxyl groups of β-D-xylofuranose in the 2- and 5-positions of formula II (R4 is an alkyl; R5 is a protecting group of hydroxyl), treating the product with a sulfide to the compound of formula III, protecting the hydroxyl in the 5-position, oxidizing the hydroxyl in the 2-position, further treating the product with a halogenating agent, and finally reacting with a base B.
KITANO KENJI
MATSUDA AKIRA
MIURA SHINJI
SASAKI TAKUMA
