Organic Chemistry: Multistep Synt#hsis, New Synthetic Methodology, Exploratory Chemistry

该计划由有机和大分子部分支持，涵盖了合成有机化学的广泛领域。几种天然存在的具有生物活性的复杂有机分子的多步合成方法正在研究中。所研究的大多数分子由于其生物活性而引起了不同寻常的兴趣。有些可能对开发新的人类治疗剂有价值。与实现简单有效地合成特定目标结构的目标携手并进的是发展新的一般合成有机反应和方法，并证明它们在选择的多步骤合成问题中的有用性。这些方法的发现扩大了合成的力量，并将其应用范围扩大到更强大的结构。在这个过程中，可以对化学的各个领域有更深的了解，例如有机金属化学和化学理论。在多步合成领域，正在开展以下具体项目：(1)手性C15银杏苷的合成；双胆碱及其类似物；(2)手性C20银杏碱酯及其类似物的合成；(3)合成苦参酮及其他血小板活化因子（PAF - ac醚，简称PAF）拮抗剂；(4)合成前avulone- a及其衍生的更复杂的海洋二十烷类化合物；(5)伪蝶苷的合成；(6) glycinoeclepin的合成；(7)炔雌醇的合成；(8)生物素合成；(9)原固醇的合成；（10）三环己戊二醇的合成。在新的合成方法领域，一些项目是针对合成中对映选择性的重要问题，包括以下内容：(1)进一步研究以扩展和扩大硼烷催化对映选择性还原的重要发现；(2)醛和酮对映选择性1,2加成；(3)铜酸盐和其他有机金属试剂对烯酮的对映选择性共轭加成；(4)催化对映选择性环丙烷化；(5)新的手性控制基团和试剂。最后，将研究一些新的方法，最终将导致新的和实用的氧化，C-C键形成和环形成反应的方法。

This program, supported by the Organic and Macromolecular section covers a broad area of synthetic organic chemistry.The synthesis by multistep processes of several naturally occurring and biologically active complex organic molecules is under study. Most of the molecules under study are of unusual interest because of their biological activities. Some may be of value in the development of new human therapeutic agents. Hand in hand with the objective of achieving simple and effective syntheses of specific target structures is the development of new general synthetic organic reactions and methods and demonstrating their usefulness in the chosen multistep synthetic problems. The discovery of such methods amplifies the power of synthesis and extends its range of application to ever more formidable structures. In the course of this effort, a deeper appreciation of various fields of chemistry, e.g. organometallic chemistry and chemical theory, can be gained. In the area of multistep synthesis the following specific projects are being carried out: (1) synthesis of chiral C15 gingkolides; bilobalide and analogs; (2) synthesis of chiral C20 gingkolides and analogs; (3) synthesis of kadsuranone and other antagonists of platelet activating factor (PAF ac ether, or simply PAF); (4) synthesis of preclavulone-A and more complex marine eicosanoids derived therefrom; (5) synthesis of pseudopterosin; (6) synthesis of glycinoeclepin; (7) synthesis of venustatriol; (8) synthesis of biotin; (9) synthesis of protosterol; (10) synthesis of tricyclohexaprenol. In the areas of new synthetic methodology a number of projects are directed at the important problem of enantioselectivity in synthesis including the following: (1) further studies to extend and broaden the important discovery of catalytic, enantioselective reductions by borane; (2) enantioselective 1,2 -addition of carbon to aldehydes and ketones; (3) enantioselective conjugate addition of cuprates and other organometallic reagents to enones; (4) catalytic enantioselective cyclopropanation; (5) new chiral controller groups and reagents. Finally, a number of new methods will be studied which ultimately will lead to new and practical methods of oxidation, C-C bond formations, and ring formation reactions.