title: Synthesis, antiproliferative, and antiviral activity of 4-amino-1-(beta-D-ribofuranosyl)pyrrolo[2,3-d]pyridazin-7(6H)-one and related derivatives.
abstract: The synthesis of 4-amino-1-beta-D-ribofuranosylpyrrolo[2,3-d]pyridazin-7 (6H)-one (3) from the reaction of ethyl 3-cyano-1-beta-D-ribofuranosylpyrrole-2-carboxylate (10) and hydrazine is described. The 5:6 pyrrolo[2,3-d]pyridazin-7(6H)-one structure of 3 was established via a three-step conversion of 3 into 1-beta-D-ribofuranosylpyrrolo[2,3-d]pyridazin-4,7(5H,6H)- dio ne (14). 4-Amino-3-chloro-1-beta-D-ribofuranosylpyrrolo[2,3-d]pyridazin+ ++-7(6H)-one (16) 4-amino-3-bromo-1-beta-D-ribofuranosylpyrrolo[2,3-d]pyridazin++ +-7(6H)-one (18) were prepared via N-chlorosuccinimide or N-bromosuccinimide treatment of 4-amino-1-(2,3,5-tri-O-benzyl-beta- D-ribofuranosyl)pyrrolo[2,3-d]pyridazin-7(6H)-one (7) followed by a removal of the benzyl groups with boron trichloride. Direct treatment of 3 with N-iodosuccinimide furnished 4-amino-3-iodo-1-beta-D-ribofuranosylpyrrolo[2,3-d]pyridazin -7(6H)-one (19). The antiproliferative activity of the compounds was determined in L1210, H. Ep. 2 and several additional human tumor cell lines. In L1210 cells, the 3-halo-substituted compounds 16, 18, and 19 exhibited significant cytotoxicity (IC50 = 0.2, 0.1, 0.08 microM, respectively), in contrast to the 3-unsubstituted compound 3, which had only slight activity. The greater antiproliferative activity of 18 and 19 in contrast to 3 was confirmed in H. Ep. 2 cells and KB cells. The antiviral evaluation of these compounds revealed that compounds 16, 18, and 19 were active against human cytomegalovirus in both plaque- and yield-reduction assays. However, this activity was only partially separated from cytotoxicity in human cell lines.
authors.affiliation: Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, Ann Arbor 48109-1065.
authors.forename: E A
authors.initials: EA
authors.lastname: Meade
authors.forename: L L
authors.initials: LL
authors.lastname: Wotring
authors.forename: J C
authors.initials: JC
authors.lastname: Drach
authors.forename: L B
authors.initials: LB
authors.lastname: Townsend
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000138:chemical synthesis* / Q000494:pharmacology; D000998:Antiviral Agents / Q000138:chemical synthesis* / Q000494:pharmacology; D002294:Carcinoma, Squamous Cell / Q000473:pathology; D002455:Cell Division / Q000187:drug effects; D003587:Cytomegalovirus / Q000187:drug effects; D018259:Herpesvirus 1, Human / Q000187:drug effects; D006801:Humans; D007939:Leukemia L1210 / Q000473:pathology; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D051379:Mice; D015394:Molecular Structure; D012263:Ribonucleosides / Q000138:chemical synthesis* / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D000998:Antiviral Agents; D012263:Ribonucleosides; C084671:4-amino-1-ribofuranosylpyrrolo(2,3-d)pyridazin-7(6H)-one