Solution Conformation of Flexible Organic Molecules

柔性有机分子的溶液构象

• 批准号: 63470011
• 负责人: OSAWA Eiji
• 金额: $ 3.2万
• 依托单位: Hokkaido University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1988
• 资助国家: 日本
• 起止时间: 1988 至 1989
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-63470011/
• 关键词: Multi-minimum problem; Conformational analysis; Structure generation program; Karplus equation; Solution conformation; Corner Flag; Structure determination; Macrolide; コ-ナ-フラップ; 改良カープラス式; NMRビジナル水素-水素結合定数; 環状配座; 新アルゴリズム

The purposes of this project is to develop new algorithms useful for the computational investigation of the multi-minimum problem in conformational analysis, to perform coding, and to apply the programs to the practical problems.By the end of the proposed term of project, all these purposes have been achieved.An entirely new algorithm, called Corner Flapping, for systematically generating all possible ring conformations was developed. It is likely that this algorithm will be the fastest of all the existing methods. The second version of the program CONFLEX2 for the execution of Corner Flapping has been deposited in public domain (QCPE #592, JCPE #21). An expanded modification of this algorithm, CONFLEX3, is almost ready at the time of writing this report. In addition, Karplus equation was extensively modified and a program for executing the multiparametric equation, 3JHHM, has been deposited in public domain (QCPE #591, JCPE #12).These computational tools have been applied to a number … More of problems encountered in experimental organic chemistry. Surprisingly large number of new conformers have been found with CONFLEX2 for tricyclo[9.3.1.0^<3.8>]pentadecane, parent skeleton of the noted natural product taxin. Active conformations of sericornine, a sex pheromone for tobacco leaf bugs, have been estimated based on a large number of energy-minimum conformers obtained by CONFLEX2. An important 16-membered ring intermediate in the synthesis of Leuconolide A was subjected to CONFLEX2 in order to obtain thermodynamically significant conformations. This large scale calculation was successfully completed, and thus opened a door to attacking similar problems, such as the analysis of Woodward's lactone closure reaction in the total synthesis of erythromycin. Finally, we are interested in determining three-dimensional structure of natural products by the combination of modified Karplus equation, 3JHHM and MM. The methodology was developed using peracetates of small aiditols as models. A success rate of 92% has so far been achieved. Less

开发新算法的目的，可用于计算多量量的形成态态，执行编码以及针对实际问题的程序。通过拟议的项目，所有这些目的都是更易于的新算法的，称为角落的算法可能是所有现有方法中最快的算法。 。化学是基于大量的能量 - 浓度 - 浓度为confllex 2，估计了烟叶虫的性爱素的浓度。热力学标志性是成功完成的R Propr物质，例如对红霉素的总合成中的木器封闭反应。

项目成果

Imai, K.; Osawa, E.: ""An Extension of Multiparametric Karplus Equation"" Tetrahedron Lett.30. 4251-4254 (1989)

今井，K.；

E.Osawa: "Application of Molecular Mechanics to Natural Product Chemistry" Pure*Appl.Chem. 61. 597-600 (1989)

E.Osawa：“分子力学在天然产物化学中的应用”Pure*Appl.Chem。

Osawa, E.; Barbiric, D. A.; Lee, O.-S.; Kitano, Y.; Padma, S.; Mehta, G.: ""1,4-Bishomo[6]prismane(Garudane): Molecular Structure and Strain Analysis of Its Reactions Potentially Leading to Prismanes"" J. Chem. Soc., Perkin Trans. II. 1161-1165 (1989)

大泽，E.；

Mehta, G.; Padma, S.; Jemmis, E. D.; Leela, G.; Osawa, E.; Barbiric, D. A.: ""Theoretical and Experimental Study of [2+2]-Photoclosure Approach toward [7]-Prismane Analogs"" Tetrahedron Lett.29,[13]. 1613-1616 (1988)

梅塔，G.；

Tsuzuki, S.; Tanabe, K.; Uchimaru, T.; Osawa, E.: ""Refinement of Molecular Mechanics Parameters-Determination of Parameters by Least Squares Method(in Japanese)"" Chem. Express. 3, [5]. 263-266 (1988)

都筑，S.；