Porphyrins and Protons

描述（由申请人提供）：该提案有两个主要焦点：铁卟啉的化学性质和与质子（H+）的化学键合性质。 广泛的目标是发现新的基础化学知识，为化学和生物系统中血红素蛋白和质子的分子水平理解提供基础。 金属卟啉研究的具体目标包括：（i）进一步开发熟悉的光谱化学系列的磁化学替代物，（ii）测试磁化学概念在一系列高铁肌红蛋白衍生物中的适用性，（iii）重新审视铁（III）卟啉中量子机械混合S = 3/2，5/2自旋态的概念，（iv）制备具有氙作为配体的锇卟啉络合物，和（v）分离“坐在顶上”的金属卟啉络合物--金属离子插入游离碱卟啉中的反应中间体。 在质子的研究中，将研究质子转移和酸催化反应化学中的中间体。 具体目标包括（i）测量基于碳硼烷的酸的酸强度，（ii）研究一类新的短、强、低势垒（SSLB）H-键，（iii）分离碳阳离子作为碳硼烷盐，（iv）研究水合氢离子（H3 O+）在缺水环境中作为酶活性位点和膜通道的模型的基本化学，以及（v）开发一种新的，强甲基化试剂。 这些研究的重点是通过X射线晶体学、各种光谱方法（NMR、IR、电子光谱，包括NIR、穆斯堡尔、共振拉曼等）对分析纯材料进行确定性表征。和理论 基础化学是生物医学科学的隐藏引擎。 碳硼烷酸在甾体代谢紊乱和MALDI蛋白质分析中具有潜在的应用价值。

DESCRIPTION (provided by applicant): This proposal has two main foci: the chemistry of iron porphyrins and the nature of chemical bonding to the proton (H+). The broad objective is to uncover new fundamental chemical knowledge that provides the basis for a molecular level understanding of hemoproteins and protons in chemical and biological systems. Specific objectives in metalloporphyrin research include: (i) the further development of a magnetochemical alternative to the familiar Spectrochemical Series, (ii) testing the applicability of the magnetochemical concept in a series of met-myoglobin derivatives, (iii) revisiting the concept of quantum mechanically admixed S = 3/2,5/2 spin states in iron(Ill) porphyrins, (iv) preparing an osmium porphyrin complex with xenon as a ligand, and (v) isolating "sitting-atop" metalloporphyrin complexes -- reaction intermediates in the insertion of metal ions into free-base porphyrins. In research on the proton, intermediates in proton transfer and acid catalyzed reaction chemistry will be investigated. Specific objectives include (i) measuring the acid strength of carborane-based acids, (ii) investigating a new class of short, strong, low-barrier (SSLB) H-bonds (iii) isolating carbocations as carborane salts, (iv) investigating the fundamental chemistry of the hydronium ion (H30+) in water-deficient environments as models for enzyme active sites and membrane channels and (v) developing the chemistry of a new, strong, methylating reagent. Emphasis in these studies is placed on the definitive characterization of analytically pure materials by X-ray crystallography, a variety of spectroscopic methods (NMR, IR, electronic spectroscopy including NIR, Mossbauer, resonance Raman, etc.) and theory. Fundamental chemistry is the hidden engine of biomedical science. There are potential applications of carborane acids in steroidal metabolism disorders and MALDI protein analysis.