title: Synthesis and biological evaluation of 2- and 7-substituted 9-deazaadenosine analogues.
abstract: A series of 2-halogen and 7-alkyl substituted analogues of 9-deazaadenosine and 2'-deoxy-9-deazaadenosine was synthesized by new efficient methodology involving transformation of corresponding 9-deazaguanosine and 2'-deoxyguanosine, which in turn were synthesized by direct C-glycosylation of 1-benzyl-9-deazaguanine with 1-O-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose and methyl 2-deoxy-3,5-di-O-(p-toluoyl)-D-ribofuranoside, respectively. Deoxychlorination of C6 and diazotization/chloroor fluoro-dediazoniation of the sugar-protected 9-deazaguanosine, followed by selective ammonolysis at C6 and deprotection of the sugar moiety, gave 2-chloro- and 2-fluoro-9-deazaadenosine (6 and 9). Substitution of the 7-position of the dihalogen-intermediate with alkyl groups, followed by ammonolysis and deprotection, provided 2-chloro-7-alkyl-9-deazaadenosines (13a-e) and 2-fluoro-7-benzyl-9-deazaadenosine (13f). Catalytic hydrogenation of 13a-e gave 7-alkyl-9-deazaadenosines 14a-e. Similarly, 2-chloro-2'-deoxy-9-deazaadenosine (21), 2-chloro-2'-deoxy-7-methyl-9-deazaadenosine (25), 2'-deoxy-9-deazaadenosine (22), and 2'-deoxy-7-methyl-9-deazaadenosine (26) were prepared from sugar-protected 2'-deoxy-9-deazaguanosine. Among these compounds, 7-benzyl-9-deazaadenosine (14b) showed the most potent cytotoxic activity, with IC50 values of 0.07, 0.1, 0.2 and 1.5 microM, while both 7-methyl-9-deazaadenosine (14a) and 2-fluoro-9-deazaadenosine (9) also demonstrated significant cytotoxic activity with IC50 values of 0.4, 0.7, 0.3, and 1.5 microM, and 1.5, 0.9, 0.3, and 5 microM against L 1210 leukemia, P388 leukemia, CCRF-CEM lymphoblastic leukemia, and B16F10 melanoma cells, respectively.
authors.affiliation: Department of Pharmacology and Developmental Therapeutics Program, Cancer Center, Yale University School of Medicine, New Haven, Connecticut, USA.
authors.forename: Mao-Chin
authors.initials: MC
authors.lastname: Liu
authors.forename: Mei-Zhen
authors.initials: MZ
authors.lastname: Luo
authors.forename: Diane E
authors.initials: DE
authors.lastname: Mozdziesz
authors.forename: Alan C
authors.initials: AC
authors.lastname: Sartorelli
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry* / Q000633:toxicity; D006801:Humans; D020128:Inhibitory Concentration 50; D007942:Leukemia, Experimental; D008545:Melanoma; D011684:Purine Nucleosides / Q000138:chemical synthesis* / Q000737:chemistry* / Q000633:toxicity; D014372:Tubercidin / Q000031:analogs & derivatives* / Q000737:chemistry*; D014407:Tumor Cells, Cultured / Q000187:drug effects
chemical_list: D000970:Antineoplastic Agents; D011684:Purine Nucleosides; C038031:9-deazaadenosine; D014372:Tubercidin