PURPOSE: To provide a new compd. which is useful as an antiviral agent, particularly an anti-human immunodeficiency virus agent for treatment and/or prophylaxis of AIDS.
CONSTITUTION: A compd. expressed by the formula or its salts are provided. In the formula, B is a natural or modified heterocyclic base linked to the sugar part through N or C in the ring; X is H, F, etc.; Y is H, sulphidryl, etc. The compd. is, for example, cyclo-2'-deoxy-(Sp)-P-thiocytidilyl-(3'→5')-2-deoxy-(Rp)-P- thiocytidilyl-(3'→5') sodium salt. The compd. is obtd. by allowing a compd. expressed by formula II (R1 is hydroxy; B' is B or B protected with an amino protecting group; Z is O, S) to react with a compd. expressed by formula III (R3 is a hydroxy protecting group which can be opened), preferably in the presence of a pivaloyl chloride or adamantoyl chloride, to obtain a compd. expressed by formula IV, then removing the protecting group R3 of the compd., changing the isolated hydroxy groups at the 3' position of the obtd. compd. into (thio) phosphate, removing R1 to obtain a compd. expressed by formula V, and then cyclizing the compd. of formula V.
SHIRUBIA FUSUTEINOONI
MARIA GABURIERA BURASUKA
DOMENIKO UNGERI
