Telomerase inhibitors

Abstract

Methods and compositions for treating cancer and other diseases in which inhibition of telomerase activity can ameliorate disease symptoms or prevent or treat the disease relate to compounds that are derivatives of pyrido�b!thiophenes, pyrido�b!furans, pyridine ethers or pyridine thioethers. Such compounds are characterized by the following structure: ##STR1## X.sub.3 is oxygen or sulfur; and the double dashed lines between X.sub.4 and X.sub.5 indicate an optional double bond, which, when present, forms a fused, bicyclic pyrido�b!furan or pyrido�b!thiophene ring system, depending upon whether X.sub.3 is oxygen or sulfur, respectively. When the double bond is not present, the compound is a monocyclic pyridine ether or thioether, again depending upon whether X.sub.3 is oxygen or sulfur. X.sub.4 is --CH.sub.2 R.sub.21 or --CR.sub.21 --, where R.sub.21 is selected from the group consisting of aryl, heteroaryl, aralkyl, heteroaralkyl, alkylcarbonyl, arylcarbonyl, heteroalkylcarbonyl, heteroaralkylcarbonyl, aralkylcarbonyl, aminocarbonyl, alkylaminocarbonyl, arylaminocarbonyl, dialkylaminocarbonyl, diarylarninocarbonyl, arylalkylaminocarbonyl, carboxyl, alkoxycarbonyl, aryloxycarbonyl, sulfo, alkylsulfonyl and arylsulfonyl; and X.sub.5 is hydrogen, alkyl, hydroxyl, alkoxyl, aryloxyl, halogen, cyano, amino, alkylamino, arylamino, dialkylamino, diarylamino, arylalkylamino, aminocarbonyl, alkylaminocarbonyl, arylaminocarbonyl, dialkylaminocarbonyl, diarylaminocarbonyl, arylalkylaminocarbonyl, carboxyl, alkoxycarbonyl, aryloxycarbonyl, sulfo, alkylsulfonyl, arylsulfonyl or --CR.sub.22 -- where R.sub.22 is selected from the group consisting of hydrogen, amino, alkylamino, arylamino, dialkylamino, diarylamino, arylalkylamino, aminocarbonyl, alkylaminocarbonyl, arylaminocarbonyl, dialkylaminocarbonyl, diarylaminocarbonyl, arylalkylaminocarbonyl, hydroxyl, halogen, cyano, carboxyl, alkoxycarbonyl and aryloxycarbonyl. When X.sub.4 is --CR.sub.21 --, X.sub.5 is --CR.sub.22 --, and X.sub.4 and X.sub.5 are joined by the above-mentioned double bond, to form thereby a fused, bicyclic pyrido�b!thiophene (X.sub.3 is sulfur) or pyrido�b!furan (X.sub.3 is oxygen) ring system. When X.sub.4 is --CH.sub.2 R.sub.21, X.sub.5 is not --CR.sub.22 --, thereby forming a pyridine ether (X.sub.3 is oxygen) or thioether (X.sub.3 is sulfur). R.sub.18 and R.sub.19 are selected independently from the group consisting of hydrogen, halogen, hydroxy, aryloxy, alkoxy, lower alkyl, aryl, heteroaryl, aralkyl and heteroaralkyl. R.sub.20 is selected from the group consisting of alkoxymethyl, dialkoxymethyl, arylalkylaminomethyl, arylaminomethyl, alkylaminomethyl, aminomethyl, diarylaminomethyl, dialkylaminomethyl, hydroximinyl, iminyl, aldehyde, alkylcarbonyl, arylcarbonyl, alkyliminyl, aryliminyl, aralkyliminyl, alkoximinyl, aryloximinyl, heterocycleimninyl, alkoxycarbonyl, aryloxycarbonyl, carboxyl, alkene, --HC.dbd.NNHR.sub.23 where R.sub.23 is selected from the group consisting of hydrogen, alkyl, aryl, aralkyl, heterocycle, heterocyclealkyl, and --C(X.sub.6)NHR.sub.24 where X.sub.6 is oxygen or sulfur and R.sub.24 is selected from the group consisting of hydrogen, aryl, arylsulfonyl, aralkyl, heterocycle and heterocyclealkyl.