title: Pyrimidine nucleotides with 4-alkyloxyimino and terminal tetraphosphate δ-ester modifications as selective agonists of the P2Y(4) receptor.
abstract: P2Y(2) and P2Y(4) receptors are G protein-coupled receptors, activated by UTP and dinucleoside tetraphosphates, which are difficult to distinguish pharmacologically for lack of potent and selective ligands. We structurally varied phosphate and uracil moieties in analogues of pyrimidine nucleoside 5'-triphosphates and 5'-tetraphosphate esters. P2Y(4) receptor potency in phospholipase C stimulation in transfected 1321N1 human astrocytoma cells was enhanced in N(4)-alkyloxycytidine derivatives. OH groups on a terminal δ-glucose phosphoester of uridine 5'-tetraphosphate were inverted or substituted with H or F to probe H-bonding effects. N(4)-(Phenylpropoxy)-CTP 16 (MRS4062), Up(4)-[1]3'-deoxy-3'-fluoroglucose 34 (MRS2927), and N(4)-(phenylethoxy)-CTP 15 exhibit ≥10-fold selectivity for human P2Y(4) over P2Y(2) and P2Y(6) receptors (EC(50) values 23, 62, and 73 nM, respectively). δ-3-Chlorophenyl phosphoester 21 of Up(4) activated P2Y(2) but not P2Y(4) receptor. Selected nucleotides tested for chemical and enzymatic stability were much more stable than UTP. Agonist docking at CXCR4-based P2Y(2) and P2Y(4) receptor models indicated greater steric tolerance of N(4)-phenylpropoxy group at P2Y(4). Thus, distal structural changes modulate potency, selectivity, and stability of extended uridine tetraphosphate derivatives, and we report the first P2Y(4) receptor-selective agonists.
authors.affiliation: Molecular Recognition Section, Laboratory of Bioorganic Chemistry, NIDDK, National Institutes of Health, Bethesda, Maryland 20892-0810, United States.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Maruoka
authors.forename: M P Suresh
authors.initials: MP
authors.lastname: Jayasekara
authors.forename: Matthew O
authors.initials: MO
authors.lastname: Barrett
authors.forename: Derek A
authors.initials: DA
authors.lastname: Franklin
authors.forename: Sonia
authors.initials: S
authors.lastname: de Castro
authors.forename: Nathaniel
authors.initials: N
authors.lastname: Kim
authors.forename: Stefano
authors.initials: S
authors.lastname: Costanzi
authors.forename: T Kendall
authors.initials: TK
authors.lastname: Harden
authors.forename: Kenneth A
authors.initials: KA
authors.lastname: Jacobson
mesh_terms: D000595:Amino Acid Sequence; D045744:Cell Line, Tumor; D004355:Drug Stability; D004952:Esters; D006801:Humans; D008024:Ligands; D008958:Models, Molecular; D008969:Molecular Sequence Data; D058910:Purinergic P2 Receptor Agonists / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D011869:Radioligand Assay; D018048:Receptors, Purinergic P2 / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship; D014500:Uracil Nucleotides / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology
chemical_list: D004952:Esters; D008024:Ligands; D058910:Purinergic P2 Receptor Agonists; D018048:Receptors, Purinergic P2; D014500:Uracil Nucleotides; C104749:purinoceptor P2Y4