The invention provides compounds of formula (I), wherein R1 and R2 have any of the values defined in the specification and salts thereof, as well as compositions comprising such compounds and therapeutic methods that utilize such compounds.
A series of novel 7-deazapurine ribonucleosides bearing an alkyl, aryl, or lietaryl group in position 6 and H, F, or Cl atom in position 7 has been prepared either by Pd-catalyzed cross-coupling reactions of the corresponding protected 6-clilot-o-(7-h ilogeiiztted-)7-deiz ipurine ribonucleosides with alkyl- or (het)arylorganometallics followed by deprotection, or by single-step aqueous phase cross-coupling reactions of unprotected 6-chloro-(7-lialogen tted-)7-de iz tl)tii-iiie ri bon ucleos ides with (het)arylboronic acids. Significant cytostatic effect was detected With a Substantial proportion ofthe prepared compounds. The most potent were 7-H or 7-17 derivatives of 6-furyl- or 6-thienyl-7-deazapurines displaying cytostatic activity in multiple cancer cell lines with a geometric mean of 50% growth inhibition concentration ranging from 16 to 96 nM, a potency comparable to or better than that of the nucleoside analogue clofarabinc. lntr icel]Lll ll'pliosphoi-yl itioil to niono- and triphosphates and the inhibition of total RNA synthesis was denionstrated in preliminary study of metabolism and tinechanistin of action Studies.