title: Synthesis and biological properties of C-2 triazolylinosine derivatives.
abstract: O(6)-(Benzotriazol-1H-yl)guanosine and its 2'-deoxy analogue are readily converted to the O(6)-allyl derivatives that upon diazotization with t-BuONO and TMS-N(3) yield the C-2 azido derivatives. We have previously analyzed the solvent-dependent azide·tetrazole equilibrium of C-6 azidopurine nucleosides, and in contrast to these, the O(6)-allyl C-2 azido nucleosides appear to exist predominantly in the azido form, relatively independent of solvent polarity. In the presently described cases, the tetrazole appears to be very minor. Consistent with the presence of the azido functionality, each neat C-2 azide displayed a prominent IR band at 2126-2130 cm(-1). A screen of conditions for the ligation of the azido nucleosides with alkynes showed that CuCl in t-BuOH/H(2)O is optimal, yielding C-2 1,2,3-triazolyl nucleosides in 70-82% yields. Removal of the silyl groups with Et(3)N·3HF followed by deallylation with PhSO(2)Na/Pd(PPh(3))(4) gave the C-2 triazolylinosine nucleosides. In a continued demonstration of the versatility of O(6)-(benzotriazol-1H-yl)purine nucleosides, one C-2 triazolylinosine derivative was converted to two adenosine analogues via these intermediates, under mild conditions. Products were desilylated for biological assays. The two C-2 triazolyl adenosine analogues demonstrated pronounced antiproliferative activity in human ovarian and colorectal carcinoma cell cultures. When evaluated for antiviral activity against a broad spectrum of DNA and RNA viruses, some of the C-2 triazolylinosine derivatives showed modest inhibitory activity against cytomegalovirus.
authors: Department of Chemistry, The City College and The City University of New York, 160 Convent Avenue, New York, New York 10031, USA. lakshman@sci.ccny.cuny.edu
authors: Mahesh K
authors: MK
authors: Lakshman
authors: Amit
authors: A
authors: Kumar
authors: Raghavan
authors: R
authors: Balachandran
authors: Billy W
authors: BW
authors: Day
authors: Graciela
authors: G
authors: Andrei
authors: Robert
authors: R
authors: Snoeck
authors: Jan
authors: J
authors: Balzarini
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D000998:Antiviral Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D049109:Cell Proliferation / Q000187:drug effects; D004267:DNA Viruses / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004354:Drug Screening Assays, Antitumor; D006367:HeLa Cells; D006801:Humans; D007288:Inosine / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D051379:Mice; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D012328:RNA Viruses / Q000187:drug effects*; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D014230:Triazoles / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D000998:Antiviral Agents; D014230:Triazoles; D007288:Inosine