SYNTHETIC ANALOGUES OF ZINC ENZYMES

描述：(改编自申请者的摘要)锌被广泛认为是 对所有形式的生命都是必不可少的，尤其是人类的生命。为 例如，锌酶5-氨基乙酰丙酸脱水酶是 血红素形成的早期步骤，而铅使其失活是 铅对人类有毒的主要原因。同样，矩阵 金属蛋白酶是一组极其重要的锌酶，它们是 参与细胞外降解和参与胚胎发育， 伤口愈合，骨骼和生长发育，以及其他生理重建 流程。然而，尽管基质金属蛋白酶有很多好处， 在正常的生物过程中，它们在病理情况下的活动 当不需要细胞外降解时，可能会产生最有害的 影响力。在这方面，不需要的基质金属蛋白酶活性一直是 与多种癌症(包括肺癌、乳腺癌和结肠癌)有关， 关节炎、多发性硬化症和阿尔茨海默病。锌也一直被 据报道，对感染有有益的治疗和预防作用 疾病和葡萄糖酸锌含片已被提出缩短长度 成人患普通感冒的风险。锌对公共健康的重要性最近已经 被强烈强调，从而使锌的生物无机化学成为 调查的基本和关键领域。为了了解众多 锌在生物系统中的作用，它首先是绝对必要的 了解锌的化学如何受其配位的调节 环境。这项建议的目的是为了获得一个透彻的了解 通过研究合成类似物来研究锌的生物无机化学 模拟锌酶活性部位的结构和功能。这 目标将通过使用特殊构造的三脚架配体来实现 提供符合结构和光谱要求的合成类似物 和机械学研究。 在上一个赠款期间，在以下方面取得了重大进展 明确的目标。具体而言，有三项成就值得进一步评论。vbl.使用 [TptBu，Me]ZnX络合物，该小组成功制备了第一对 氢氧化锌、水锌络合物。研究了氢氧化锌的可逆质子化反应. 演示使用一种新型的Bronsted酸来克服不稳定的问题 水的配体。有了这两个络合物，差异反应性 对二氧化碳的研究得到了证实。第二，该集团已取得重大进展 配体(及相应的金属配合物)的制备研究进展 提供混合捐赠者的机构，例如[N2O]或[N2S]。第三，反应性建模。 拉达的发展已经取得了巨大的进步。制备了醇锌衍生物 并在结构上进行了验证。酒精交换反应允许 热力学参数的提取。最后，也是最值得注意的是，锌 醇盐与醛反应生成与“氢化物”一致的产物 转移；拉丁脱氢酶催化的关键步骤。作为优秀的另一个标志 生产力，已有11篇论文发表或提交在 上一个授权期。

DESCRIPTION: (Adapted from applicant's abstract) Zinc is widely recognized as being essential to all forms of life, and in particular that of humans. For example, the zinc enzyme 5-aminolevulinate dehydratase is necessary for the early steps of heme formation, and its inactivation by lead is one of the principal reasons why lead is poisonous to humans. Likewise, matrix metalloproteinases are an extremely important group of zinc enzymes that are involved in extracellular degradation and participate in embryonic development, wound healing, bone and growth development, and other physiological remodeling processes. However, despite the beneficial aspects of matrix metalloproteinases during normal biological processes, their activity in pathological situations when extracellular degradation is not required may have a most detrimental influence. In this regard, undesired matrix metalloprotease activity has been linked to a variety of cancers (including lung, breast, and colon cancer), arthritis, multiple sclerosis, and Alzheimer's disease. Zinc has also been reported to have beneficial therapeutic and preventative effects on infectious diseases and zinc gluconate lozenges have been proposed to shorten the length of the common cold in adults. The public health importance of zinc has recently been strongly emphasized, thereby making the bioinorganic chemistry of zinc an essential and critical area of investigation. In order to understand the many roles of zinc in biological systems, it is first absolutely essential to understand how the chemistry of zinc is modulated by its coordination environment. The intent of this proposal is to obtain a thorough understanding of the bioinorganic chemistry of zinc by investigating synthetic analogues that mimic both the structure and function of the active sites of zinc enzymes. This objective will be achieved by using specially constructed tripod ligands to afford synthetic analogues that will be amenable to structural, spectroscopic and mechanistic studies. During the previous grant period significant progress was made toward the stated goals. Specifically, three accomplishments merit further comment. Using [TptBu,Me]ZnX complexes, the group successfully prepared the first pair of Zn-hydroxide, Zn-aqua complexes. Reversible protonation of a Zn-hydroxide was demonstrated using a novel Bronsted acid to overcome problems of lability of the water ligand. With these two complexes in hand, differential reactivity toward carbon dioxide was demonstrated. Second, the group has made major progress in the preparation of ligands (and the corresponding metal complexes) that provide mixed donors, e.g. [N2O] or [N2S]. Third, the reactivity modeling of LADH has progressed enormously. Zinc alkoxide derivatives have been prepared and structurally authenticated. Alcohol exchange reactions have allowed for the extraction of thermodynamic parameters. Finally, and most notably, the zinc alkoxides react with aldehyde to yield products consistent with "hydride" transfer; the key step in LADH catalysis. As another marker of excellent productivity, eleven papers have either been published or submitted in the previous grant period.