X-Ray and Chemical Studies of Metalloporphyrins

描述(申请人提供)：建议合成和表征多种新的金属卟啉化合物。这项工作将强调但不限于，卟啉铁衍生物。大多数被建议研究的化合物与血红素蛋白衍生物有关，它们具有广泛的生物学功能，包括氧的利用、储存和运输、基于NO的信号转导、电子传递、药物代谢和其他酶过程。三维X射线晶体结构测定方法将被应用于确定金属卟啉立体化学的分子结构和各个细节方面。核共振振动光谱(NRVS)新技术正被用来定义生物分子中的铁的动力学。NRVS方法允许观察其中有铁运动的所有振动模型。NRVS已经产生了有趣的振动数据，这是任何其他技术都无法获得的，包括检测六个咪唑连接的CO衍生物中的Fe-Im模。它将使我们了解蛋白质环境如何改变铁的动态，从而改变反应模式。将酌情应用的其他方法包括通过块体温度相关磁化率和电子顺磁共振(EPR)测量、穆斯堡尔谱、振动和UV-Vis光谱以及电化学性质来表征磁性。最广义地说，研究目标是实现金属卟啉的结构和物理性质的合成，特别是因为这些关系与理解基于血球蛋白的生物过程有关。将被研究的铁卟啉包括一些六配位的衍生物，[Fe(Por)(XO)(Im)](XO=O2，CO，NO)，以考察当相反配体改变时Fe-Im振动的变化，这对于理解血红蛋白氧结合协作性问题很重要。其他项目包括详细研究高自旋五配位铁(II)物种的结构和电子结构，额外的亚硝基配合物，合成细胞色素b和c的类似物，以显示轴向配体取向如何影响它们的电子结构和氧化还原性能。

DESCRIPTION (provided by applicant): The synthesis and characterization of a variety of new metalloporphyrin compounds is proposed. The work will emphasize, but will not be limited to, iron porphyrinate derivatives. Most classes of compounds proposed for study are related to hemoprotein derivatives, which carry out a wide range of biological functions including oxygen utilization, storage and transport, NO-based signaling, electron transport, drug metabolism and other enzymatic processes. The methods of three-dimensional X-ray crystal structure determination will be applied to define molecular structures and various detailed aspects of metalloporphyrin stereochemistry. The new technique of nuclear resonance vibrational spectroscopy (NRVS) is being used to define iron dynamics in biomolecules. The NRVS method allows the observation of all vibrational models in which there is movement of the iron. NRVS has already yielded interesting vibrational data not available by any other technique including the detection of the Fe-Im mode in six-coordinate imidazole-ligated CO derivatives. It will allow an understanding of how the protein environment can change iron dynamics and hence reactivity patterns. Other methodologies to be applied, as appropriate, include characterization of magnetic properties by bulk temperature-dependent susceptibility and electron paramagnetic resonance (EPR) measurements, Mossbauer, vibrational and UV-vis spectroscopy, and electrochemical properties. The research objectives, stated in the broadest terms, are to achieve a synthesis of the structural and physical properties of metalloporphyrins, particularly as these relationships pertain to an understanding of hemoprotein-based biological processes. Iron porphyrinates to be studied include a number of six-coordinate derivatives, [Fe(Por)(XO)(Im)] (XO = O2, CO, NO), in order to examine changes in the Fe-Im vibrations as the opposite ligand is changed, important for understanding issues in hemoglobin oxygen-binding cooperativity. Other projects include detailed study of structure and electronic structure of high-spin five coordinate iron(II) species, additional nitrosyl complexes, synthetic analogues of cytochromes b and c to show how axial ligand orientation affects their electronic structure and oxidation-reduction properties.