Methanocarba modification of uracil and adenine nucleotides:: High potency of northern ring conformation at P2Y1, P2Y2, P2Y4, and P2Y11 but not P2Y6 receptors
Methanocarba modification of uracil and adenine nucleotides:: High potency of northern ring conformation at P2Y1, P2Y2, P2Y4, and P2Y11 but not P2Y6 receptors
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DOI：
10.1021/jm010369e
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发表时间：
2002-01-03
影响因子：
7.3
通讯作者：
Jacobson, KA
中科院分区：
文献类型：
--
作者：
Kim, HS;Ravi, RG;Jacobson, KA
核苷酸拮抗剂对P2 Y（1）受体的效力通过用受约束的碳环取代核糖部分而增强（Nandanan，et al.J.Med.Chem.2000，43，829842）。我们现在已经合成了腺嘌呤和尿嘧啶核苷酸（P2 Y受体的内源性激活剂）的环约束甲烷卡巴类似物（其中稠合的环丙烷部分约束假糖环）。甲烷卡巴-腺苷5 '-三磷酸（ATP）固定为北方（N）或南方（S）构象，如假旋转循环中所定义。通过用β-乙氧基丙烯酰氰酸酯处理1-氨基-假糖环并环化形成尿嘧啶环来制备（N）-甲烷卡巴尿苷。通过多步过程在5 '-羟基上进行磷酸化：与亚磷酰胺反应，然后氧化，得到5 ′-单磷酸酯，然后用1，1 ′-羰基二咪唑处理，与另外的磷酸酯基团缩合。类似物通过激活火鸡P2 Y（1）或人P2 Y（1），P2 Y（2），P2 Y（4），测定星形细胞瘤细胞中稳定表达的P2 Y（6）和P2 Y（11）受体。在重组人P2 Y（1）和P2 Y（2）受体上，（N）-甲烷卡巴-ATP作为激动剂的效力分别是外消旋（S）-甲烷卡巴-ATP的138倍和41倍。（N）甲烷卡巴-ATP激活P2 Y（11）受体，其效力与ATP相似。（N）-甲卡巴尿苷5 '-三磷酸（UTP）作为人P2 Y2受体的激动剂与UTP等效，也激活P2 Y（4）受体，EC 50为85 nM。（N）-甲硫卡巴尿苷5 '-二磷酸（UDP）对hP 2 Y（6）受体无活性。在大鼠肠系膜动脉模型中研究了（N）-甲烷卡巴-UTP和（N）-甲烷卡巴-UDP的血管效应。三磷酸盐在诱导扩张性P2 Y（4）反应方面比UTP更有效（pEC（50）= 6.1 +/- 0.2），而二磷酸盐在P2 Y（6）受体介导的收缩反应中作为激动剂或拮抗剂均无活性。我们的研究结果表明，新的核苷酸激动剂可以设计的基础上（N）构象，有利于选择性P2 Y（1），P2 Y（2），P2 Y（4），和P2 Y（11）受体。
The potency of nucleotide antagonists at P2Y(1) receptors was enhanced by replacing the ribose moiety with a constrained carbocyclic ring (Nandanan, et al. J. Med. Chem. 2000, 43, 829842). We have now synthesized ring-constrained methanocarba analogues (in which a fused cyclopropane moiety constrains the pseudosugar ring) of adenine and uracil nucleotides, the endogenous activators of P2Y receptors. Methanocarba-adenosine 5'-triphosphate (ATP) was fixed in either a Northern (N) or a Southern (S) conformation, as defined in the pseudorotational cycle. (N)-Methanocarba-uridine was prepared from the 1-amino-pseudosugar ring by treatment with beta-ethoxyacryloyl cyanate and cyclization to form the uracil ring. Phosphorylation was carried out at the 5'-hydroxyl group through a multistep process: Reaction with phosphoramidite followed by oxidation provided the 5'-monophosphates, which then were treated with 1,1'-carbonyldiimidazole for condensation with additional phosphate groups, The ability of the analogues to stimulate phospholipase C through activation of turkey P2Y(1) or human P2Y(1), P2Y(2), P2Y(4), P2Y(6), and P2Y(11) receptors stably expressed in astrocytoma cells was measured. At recombinant human P2Y(1) and P2Y(2) receptors, (N)-methanocarba-ATP was 138- and 41-fold, respectively, more potent than racemic (S)-methanocarba-ATP as an agonist. (N)methanocarba-ATP activated P2Y(11) receptors with a potency similar to ATP. (N)-Methanocarba-uridine 5'-triphosphate (UTP) was equipotent to UTP as an agonist at human P2Y2 receptors and also activated P2Y(4) receptors with an EC50 of 85 nM. (N)-Methanocarba-uridine 5'-diphosphate (UDP) was inactive at the hP2Y(6) receptor. The vascular effects of (N)-methanocarba-UTP and (N)-methanocarba-UDP were studied in a model of the rat mesenteric artery, The triphosphate was more potent than UTP in inducing a dilatory P2Y(4) response (pEC(50) = 6.1 +/- 0.2), while the diphosphate was inactive as either an agonist or antagonist in a P2Y(6) receptor-mediated contractile response. Our results suggest that new nucleotide agonists may be designed on the basis of the (N) conformation that favors selectivity for P2Y(1), P2Y(2), P2Y(4), and P2Y(11) receptors.