New Methods for Simultaneous Arming and SAR Studies of Natural Products

天然产物同时武装和SAR研究的新方法

• 批准号: 7693246
• 负责人: DANIEL ROMO
• 金额: $ 22万
• 依托单位: TEXAS A&M UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-12 至 2011-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7693246
• 关键词: Alkenes; Alkynes; Amination; Apoptosis; Biological; Biological Assay; Biological Factors; Cellular Assay; Cellular biology; Classification; Collaborations; Complex; Cross-Linking Reagents; Development; Diabetes Mellitus; Disease; Ensure; Genomics; Goals; Grant; Head; High Pressure Liquid Chromatography; Human; Inflammation; Iodination reaction; Lead; Malignant Neoplasms; Mediating; Metals; Methods; Mining; Molecular; Molecular Bank; Monitor; Neurites; Numbers; Organism; Pathway interactions; Proteins; Public Health; Range; Reaction; Reagent; Recording of previous events; Research; Scheme; Screening procedure; Site; Structure; T-Cell Activation; Translations; Upper arm; chemical genetics; cycloaddition; design; drug development; functional group; halogenation; human disease; inhibitor/antagonist; metal complex; novel; novel therapeutics; receptor; repository; small molecule; therapeutic target; tool

DESCRIPTION (provided by applicant): Natural products have immense structural diversity and interact with a wide range of proteins in diverse organisms and, due to structural homology, also in humans. This proposal seeks to develop a toolbox of reagents and reactions that will enable simultaneous arming and structure- activity studies (SAR) of natural products (NPs). The SAR studies may identify potential new activities of the NP derivatives and will also ensure that initial biological activity has not been lost. While not a Specific Aim of this grant given the scope of this RFA, the arming aspect leads to NP derivatives that are equipped for subsequent conjugation to various tags via Sharpless-Huisgen cycloadditions, enabling biological studies such as mechanism of action (MOA) studies (including off-targets) and provide useful probes for basic cell biology. The long-term objective is to develop a more systemized approach to mine the rich potential of NPs as activators/inactivators of cellular pathways contributing to chemical genetics. The team includes a synthetic organic chemist (D. Romo), an analytical chemist (G. Vigh), a bioorganic/biosynthetic chemist (C. Watanabe), and a biochemist/molecular biologist (J. Liu, Johns Hopkins). We propose to further develop a set of chemo- and site selective reactions employing bifunctional reagents to obtain NP derivatives that are also useful cellular probes. These studies will contribute to a fundamental understanding of the chemo- and site selectivity of various reactions in the context of complex NPs. We have established collaborations with synthetic, biosynthetic, and isolation chemists and they have provided or agreed to provide ~25 bioactive NPs for the proposed studies. Primary reactions to be studied are Rh(II)-promoted O-H insertion reactions, C-H aminations and alkene aziridinations with metal nitrenoids, and mild aryl halogenations. After an initial site non-selective step, we will employ robust/versatile NP derivative purification methods, re- assay the resulting pure derivatives (SAR studies), and determine the most appropriate site for tag attachment, i.e. find the derivatives that retain the greatest bioactivity. We will also screen for potential novel bioactivities of the NP derivatives in various cellular assays and make quantities available to the Molecular Libraries Small Molecule Repository. The subsequent development of both chemo and site-selective versions of the initial reactions will rely on screening various chiral metal complexes, and robust methods for reaction monitoring (LC-MSn) and semi-preparative HPLC purification, to modulate site-selectivity via a type of "double asymmetric synthesis." PUBLIC HEALTH RELEVANCE: The long-term objective of this project is the development of a more systematized approach to mine the rich potential of natural products as activators and inactivators of cellular pathways. Natural products have a rich history as tools for identification of novel therapeutic targets for human disease and as lead structures for drug development. Results from these studies will be directly relevant to human disease including diabetes, inflammation, and cancer since novel methods are proposed for derivatization of natural products (this proposal) pertinent to these disease. Subsequent SAR studies (this proposal) will be pursued to identify potential new bioactivities and suitable sites for probe attachment enabling subsequent mode of action studies (not in this proposal) relevant to these diseases.

描述（由申请人提供）：天然产物具有巨大的结构多样性，并与不同生物体中的多种蛋白质相互作用，并且由于结构同源性，也与人类中的蛋白质相互作用。该提案旨在开发一个试剂和反应工具箱，以实现天然产物（NP）的同步武装和结构活性研究（SAR）。 SAR研究可以确定NP衍生物的潜在新活性，并且还将确保最初的生物活性没有丧失。虽然考虑到本​​ RFA 的范围，武装方面不是本次资助的具体目标，但武装方面导致了 NP 衍生物，这些衍生物可以通过 Sharpless-Huisgen 环加成随后与各种标签缀合，从而实现作用机制 (MOA) 研究等生物学研究。包括脱靶）并为基础细胞生物学提供有用的探针。长期目标是开发一种更加系统化的方法来挖掘纳米粒子作为有助于化学遗传学的细胞途径激活剂/灭活剂的丰富潜力。该团队包括合成有机化学家（D. Romo）、分析化学家（G. Vigh）、生物有机/生物合成化学家（C. Watanabe）和生物化学家/分子生物学家（J. Liu，约翰霍普金斯大学）。我们建议进一步开发一套使用双功能试剂的化学和位点选择性反应来获得也可作为有用的细胞探针的纳米颗粒衍生物。这些研究将有助于对复杂纳米颗粒背景下各种反应的化学选择性和位点选择性的基本理解。我们已经与合成、生物合成和分离化学家建立了合作，他们已经为拟议的研究提供或同意提供约 25 种生物活性纳米颗粒。要研究的主要反应是 Rh(II) 促进的 O-H 插入反应、C-H 胺化反应和与金属氮烯类化合物的烯烃氮丙啶化反应，以及温和的芳基卤化反应。在初始位点非选择性步骤之后，我们将采用稳健/多功能的 NP 衍生物纯化方法，重新测定所得纯衍生物（SAR 研究），并确定最合适的标签附着位点，即找到保留最大的衍生物生物活性。我们还将在各种细胞测定中筛选 NP 衍生物的潜在新颖生物活性，并将数量提供给分子图书馆小分子存储库。初始反应的化学和位点选择性版本的后续开发将依赖于筛选各种手性金属配合物，以及用于反应监测（LC-MSn）和半制备型 HPLC 纯化的稳健方法，以通过类型调节位点选择性“双重不对称合成”。 公共健康相关性：该项目的长期目标是开发一种更加系统化的方法来挖掘天然产物作为细胞途径激活剂和灭活剂的丰富潜力。天然产物作为识别人类疾病新治疗靶点的工具和作为药物开发的先导结构具有丰富的历史。这些研究的结果将与包括糖尿病、炎症和癌症在内的人类疾病直接相关，因为提出了与这些疾病相关的天然产物的衍生化新方法（本提案）。随后的 SAR 研究（本提案）将致力于确定潜在的新生物活性和探针附着的合适位点，从而能够进行与这些疾病相关的后续作用模式研究（不在本提案中）。