1,3-Substituted pyrazolo[3,4-b]pyridinones 11-18 were synthesized by a three-component condensation of Meldrum's acid with aryl aldehydes and 1,3-substituted 5-aminopyrazoles. Their biological activity was evaluated using the in vivo phenotypic sea urchin embryo assay and the in vitro cytotoxicity screen against human cancer cell lines. In the sea urchin embryo model, 1-benzimidazolyl-pyrazolo[3,4-b]pyridinones 11 caused inhibition of hatching and spiculogenesis at sub-micromolar concentrations. These compounds also selectively and potently inhibited growth of the MOLT-4 leukemia cell line. Subsequent structure-activity relationship studies determined the benzimidazolyl fragment as an essential pharmacophore for both effects. We applied numerous techniques for target identification. A preliminary QSAR target identification search did not result in tangible leads. Attempts to prepare a relevant photoaffinity probe that retained potency in both assays were not successful. Compounds 11 were further characterized for their activity in a wild-type versus Notch-mutant leukemia cell lines, and in in vitro panels of kinases and matrix metalloproteinases. Using a series of diverse modulators of spiculogenesis as standards, we excluded multiple signaling networks including Notch, Wnt/β-catenin, receptor tyrosine kinases (VEGF/VEGFR, FGF/FGFR), PI3K, and Raf-MEK-ERK as possible targets of 11. On the other hand, matrix metalloproteinase-9/hatching enzyme was identified as one potential target.

中文翻译：

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苯并咪唑基-吡唑并[3,4-b]吡啶并酮，MOLT-4白血病细胞生长和海胆胚胎螺旋形成的选择性抑制剂：目标研究。

1,3-取代的吡唑并[3,4-b]吡啶并酮11-18是通过Meldrum酸与芳基醛和1,3-取代的5-氨基吡唑的三组分缩合反应合成的。使用体内表型海胆胚胎测定法和针对人类癌细胞系的体外细胞毒性筛选法评估了它们的生物学活性。在海胆胚胎模型中，1-苯并咪唑基-吡唑并[3,4-b]吡啶酮11会在亚微摩尔浓度下抑制孵化和spiculogenesis。这些化合物还选择性和有效地抑制了MOLT-4白血病细胞系的生长。随后的结构-活性关系研究确定了苯并咪唑基片段是这两种作用的必不可少的药效基团。我们应用了许多技术来进行目标识别。初步的QSAR目标识别搜索未发现有形的线索。尝试制备在两种测定法中均保留效力的相关光亲和性探针的尝试均未成功。进一步表征化合物11在野生型与Notch突变型白血病细胞系中以及在激酶和基质金属蛋白酶的体外组中的活性。我们使用一系列的脉冲形成调节剂作为标准，我们排除了包括Notch，Wnt /β-catenin，受体酪氨酸激酶（VEGF / VEGFR，FGF / FGFR），PI3K和Raf-MEK-ERK在内的多个信号网络11.另一方面，基质金属蛋白酶9 /孵化酶被鉴定为一个潜在的靶标。进一步表征化合物11在野生型与Notch突变型白血病细胞系中以及在激酶和基质金属蛋白酶的体外组中的活性。我们使用一系列的脉冲形成调节剂作为标准，我们排除了包括Notch，Wnt /β-catenin，受体酪氨酸激酶（VEGF / VEGFR，FGF / FGFR），PI3K和Raf-MEK-ERK在内的多个信号网络11.另一方面，基质金属蛋白酶9 /孵化酶被鉴定为一个潜在的靶标。进一步表征化合物11在野生型与Notch突变型白血病细胞系中以及在激酶和基质金属蛋白酶的体外组中的活性。我们使用一系列的脉冲形成调节剂作为标准，我们排除了包括Notch，Wnt /β-catenin，受体酪氨酸激酶（VEGF / VEGFR，FGF / FGFR），PI3K和Raf-MEK-ERK在内的多个信号网络11.另一方面，基质金属蛋白酶9 /孵化酶被鉴定为一个潜在的靶标。