Tetrahydroisoquinoline Antitumor Drugs: Synthesis and Biosynthesis

描述（由申请人提供）：本申请的主要重点是研究由四氢异喹啉构成的复杂的、具有生物医学意义的天然产物的全合成和生物合成。将开发的合成化学将用于制备天然物质的类似物，如生物，生物合成和机械探针。该建议主要是假设驱动的，并广泛采用在本实验室开发的新的合成方法来构建此类制剂。本项目的具体目的是研究天然抗肿瘤抗生素和机械激发的合成类似物，包括卵磷脂酸743 （Et-743）、萨福霉素、乔霉素、四zomine、柠檬霉素和生物沙霉素与细胞核酸的相互作用。将这些药物的dna烷基化能力与它们对核酸的氧化损伤能力进行比较。这类抗肿瘤药物的合成将继续发展，目的是利用已开发的合成方法来制造新的、毒性更小、更具选择性和更有效的抗肿瘤药物。此外，合成工具将被用于合成这些物质与细胞核酸和结合细胞核酸的蛋白质相互作用的机制探针。我们最近发现生物沙霉素12在54dCpG34步骤特异性交联双链DNA。我们建议阐明共价加合物的确切分子结构。这一发现激发了基于四氢异喹啉核心的更简单类似物的新设计概念，这些类似物可能能够烷基化和交联DNA，也可能将DNA与DNA结合蛋白交联。该生物碱家族的抗增殖活性与这些制剂结合和共价修饰DNA的能力密切相关。这在Et-743的案例中尤为明显。提出了将这些试剂的DNA烷基化和交联化学与它们对细胞造成氧化损伤的能力机械分离的计划。Et-743的生物合成研究将重点放在大环硫化物桥接螺-四氢异喹啉环体系的后期组装上。我们计划采用高通量基因组测序方法，利用454技术鉴定外海鞘Et-743生物合成基因簇。生物合成研究的最终目标是对一种可发酵微生物进行基因工程改造，以生产用于临床的Et-743。公共卫生相关性：本应用程序的目的是利用化学合成的工具来研究自然界如何生物合成抗癌药物的分子细节。特别是，通过微生物宿主的基因工程，将利用新技术生产临床相关的抗癌药物ecteinascidin 743 （Et-743）。此外，正在开发的化学技术将应用于设计和合成新的抗癌药物。

DESCRIPTION (provided by applicant): The primary focus of this application is to study the total synthesis and biosynthesis of complex, biomedically significant natural products constituted of tetrahydroisoquinolines. The synthetic chemistry that will be developed shall be utilized to prepare analogues of the natural substances as biological, biosynthetic and mechanistic probes. This proposal is primarily hypothesis-driven, and extensively employs new synthetic methodologies developed in this laboratory for the construction of such agents. The specific aims of this program are to study the interaction of the natural antitumor antibiotics and mechanistically inspired synthetic analogs, including ecteinascidin 743 (Et-743), saframycin, jorumycin, tetrazomine, lemonomycin and the bioxalomycins with cellular nucleic acids. The DNA-alkylating capacity of these drugs compared with their ability to cause oxidative damage to nucleic acids will be explored. The synthesis of members of this class of antitumor drugs will continue to be developed with the objective of harnessing the synthetic methodology developed to make new, less toxic, more selective and more potent antitumor drugs. In addition, the tools of synthesis will be exploited to synthesize mechanistic probes for the interaction of these substances with cellular nucleic acids and proteins that bind to cellular nucleic acids. We have recently discovered that bioxalomycin 12 specifically cross-links duplex DNA at 54dCpG34 steps. We propose to elucidate the exact molecular structure of the covalent adduct. This finding has inspired new design concepts for simpler analogs based on the tetrahydroisoquinoline core that may be capable of alkylating and cross-linking DNA as well as potentially cross-linking DNA to DNA-binding proteins. The antiproliferative activity of this family of alkaloids is intimately associated with the capacity of these agents to bind to and covalently modify DNA. This is particularly evident in the case of Et-743. Plans are presented to mechanistically separate the DNA alkylation and cross-linking chemistry of these agents from their capacity to inflict oxidative damage on cells. The investigation of the biosynthesis of Et-743 with a particular focus on the late-stage assembly of the macrocyclic sulfide-bridged spiro-tetrahydroisoquinoline ring system will be pursued. We plan to apply high throughput genome sequencing methods using 454 technology to identify the Et-743 biosynthetic gene cluster from Ecteinascidia turbinata. The ultimate goals of the biosynthesis studies are to genetically engineer a fermentable microorganism to produce Et-743 for clinical use. PUBLIC HEALTH RELEVANCE: The purpose of this application is to utilize the tools of chemical synthesis to study the molecular details of how Nature biosynthesizes anti-cancer drugs. In particular, this program will deploy new technologies to produce the clinically relevant anticancer drug ecteinascidin 743 (Et-743) on industrially practical scale through genetic engineering of a microbial host. In addition, the chemical technologies being developed will be applied to the design and synthesis of new anti-cancer drugs.