title: Synthesis and biological evaluation of 9-deazaguanine derivatives connected by a linker to difluoromethylene phosphonic acid as multi-substrate analogue inhibitors of PNP.
abstract: 9-(5',5'-difluoro-5'-phosphonopentyl)-9-deazaguanine (DFPP-DG) was designed as a multi-substrate analogue inhibitor against purine nucleoside phosphorylase (PNP) on the basis of X-ray crystallographic data obtained for a binary complex of 9-(5',5'-difluoro-5'-phosphonopentyl)guanine (DFPP-G) with calf spleen PNP. DFPP-DG and its analogous compounds were adjusted by length of the linker achieved by the Sonogashira-coupling reaction between a 9-deaza-9-iodoguanine derivative and omega-alkynyldifluoromethylene phosphonates as a key reaction. DFPP-DG is a very potent PNP inhibitor with apparent inhibition constants (in the presence of 1 mM phosphate) of 4.4 and 8.1 nM versus calf spleen and human erythrocyte PNPs, respectively. One of its analogues, homo-DFPP-DG, with longer chain linking phosphonate and 9-deazaguanine is even more potent versus human enzyme, with an apparent inhibition constant of 5.3 nM (in the presence of 1mM phosphate).
authors.affiliation: School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
authors.forename: Sadao
authors.initials: S
authors.lastname: Hikishima
authors.forename: Mariko
authors.initials: M
authors.lastname: Hashimoto
authors.forename: Lucyna
authors.initials: L
authors.lastname: Magnowska
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Bzowska
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Yokomatsu
mesh_terms: D000818:Animals; D002417:Cattle; D004002:Clodronic Acid / Q000031:analogs & derivatives* / Q000737:chemistry; D004791:Enzyme Inhibitors / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D004912:Erythrocytes / Q000187:drug effects / Q000201:enzymology; D006147:Guanine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D006801:Humans; D008958:Models, Molecular; D011683:Purine-Nucleoside Phosphorylase / Q000037:antagonists & inhibitors* / Q000097:blood / Q000378:metabolism; D013154:Spleen / Q000187:drug effects / Q000201:enzymology; D013379:Substrate Specificity
chemical_list: D004791:Enzyme Inhibitors; D004002:Clodronic Acid; C041121:difluoromethylene diphosphonate; D006147:Guanine; C076777:9-deazaguanine; D011683:Purine-Nucleoside Phosphorylase