Anti-retroviral compound

NEW MATERIAL: Compds. of formula: A-B-C [wherein A and C are each dideoxynucleoside; B is -C(X)-(CH 2 ) m -C(X)- (in which X is O or S; and n is 2 to 6), -C(X)- or the like; B is bonded to A at 4-amino group or 5'-hydroxyl group of A, and C is bonded to B at 4-amino group or 5'-hydroxyl group of C]. EXAMPLE: 2',3'-Deoxy-5-[[1-[2',3'-dideoxy-5'O[(1,1-dimethylethyl) dimethylsilyl]pentofuranosyl]-1,2-dihydro-2-oxo-4-pyrimidinyl]amino]cytidine 5'-(5-oxo-pentanoate) (ester). USE: Antiretroviral agent. PROCESS: 5'-OH group or the like of 2',3'-dideoxy-nucleoside of AH of CH is protected to form A'H or C'H, which is reacted with a bifunctional reagent derived from a bonding group B, and the blocking group is removed. COPYRIGHT: (C)1990,JPO