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Electronic Structure And Reactivity Of Bioinspired Organometallic Iron Complexes Relevant To Small Molecule Activation
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Book Synopsis Electronic Structure and Reactivity of Bioinspired Organometallic Iron Complexes Relevant to Small Molecule Activation by : Claudia Gisela Kupper
Download or read book Electronic Structure and Reactivity of Bioinspired Organometallic Iron Complexes Relevant to Small Molecule Activation written by Claudia Gisela Kupper and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Activation of Small Molecules by : William B. Tolman
Download or read book Activation of Small Molecules written by William B. Tolman and published by John Wiley & Sons. This book was released on 2006-12-13 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first to combine both the bioinorganic and the organometallic view, this handbook provides all the necessary knowledge in one convenient volume. Alongside a look at CO2 and N2 reduction, the authors discuss O2, NO and N2O binding and reduction, activation of H2 and the oxidation catalysis of O2. Edited by the highly renowned William Tolman, who has won several awards for his research in the field.
Book Synopsis Low-Valent Iron and Cobalt Isocyanide Complexes by : Charles Cameron Mokhtarzadeh
Download or read book Low-Valent Iron and Cobalt Isocyanide Complexes written by Charles Cameron Mokhtarzadeh and published by . This book was released on 2017 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation describes the targeted attempts at the generation of transition metal species that function as precise electronic structure mimics to the well known spin triplet (S =1) metal carbonyls fragments Fe(CO)4 and CpCo(CO). These unsaturated fragments have been shown to display a wide range reactivity, and competency towards important reaction chemistry such as alkane and N2 binding, and E-H bond activation due to a unique interplay of a strong ligand field, formal dn count, and orbital symmetry, rendering these fragments primed for bond activation. Accordingly, ligand architectures that can accurately mimic the ligand field provided by CO to kinetically stabilize these fragments could provide new inroads to novel small molecule activation pathways. To this end, sterically encumbering m-terphenyl isocyanides serve as isolobal ligand surrogates for carbon monoxide (CO). Additionally isocyanides have the added benefit of providing kinetic stabilization by virtue of readily tunable isocyano-R (CN-R) group. The first section of this dissertation describes the synthesis and protonation of an encumbered tetra-isocyanide iron dianion, Na2[Fe(CNArMes2)4] (ArMes2 = 2,6-(2,4,6 --Me3C6H2)2C6H3), which serves as a platform for targeting species of the formulation Fe(CNArMes2)4. It is shown that the reactivity of the electronically unsaturated Fe(CNR)4 fragment upon protonation of Na2[Fe(CNArMes2)4] and subsequent alkylation of Na[HFe(CNArMes2)4], yields the dinitrogen stabilized species Fe(N2)(CNArMes2)4. Fe(N2)(CNArMes2)4 is shown to readily undergo intramolecular C-H activation of the ligand scaffold upon liberation N2 under ambient conditions purportedly through and insipient [Fe(CNArMes2)4] fragment. Further more, ability of Na2[Fe(CNArMes2)4] to facilitate the reductive disproportionation of CO2, in addition to CO2 capture with electrophilic silyl sources is presented culminating in a rare class of low valent Fe-aminocarbyne complexes. The second vignette of this dissertation focuses on the generation of species that mimic the formulation CpCo(L). It is shown that with less encumbering m-terphenyl isocyanides that aggregation akin to the unsaturated carbonyl congeners is realized. Use of encumbering m-terphenyl isocyanides provides access to the three memebered electron transfer series [([mu]2-CNArMes2)2[CpCo]2]n (n = 0,-1, -2). Notably, this series is the first of its kind to span all three ostensible electronic states (e.g. d8-d8, d8-d9, and d9-d9), previously unavailable with other [pi]-acidic ligand frameworks. Additionally this allows for a systematic reassessment of the metal-metal bonding within this class of dimeric species. Evidence is put forth in favor of no M-M bonding interactions occur within these systems and the integrity of the dimeric framework is in fact mitigated through a unique interplay of the metal d-manifold and the isocyanide [pi]*-system. Modulation of the steric profile of the m-terphenyl isocyanide and the Cp unit to Cp* so as to increase the steric pressure provides access to the first reported mono-nuclear Cp*Co(N2)L fragments. It is shown that these species function as viable sources of Cp*Co(CNR) for a number of bond activation processes including Si-H, H-H, and P-P bond scission. Moreover, the reactivity of these species culminates with the isolation of the second example of a structurally authenticated transition metal nitrous oxide (N2O) adduct, which exhibits an unprecedented [eta]2-(N,N) coordination mode to Co. Finally, the reduction of the encumbered Cp*Co(CNArTripp2) (CNArTripp2 2,6-(2,4,6-(i-Pr)3C6H3)2C6H3) fragment provide access to the unique dianion K2[Cp*Co≡CNArTripp2]. It is shown that the dianion K2[Cp*Co≡CNArTripp2] exhibits 3-fold bonding between Co and the isocyanide -Ciso through an extreme case of M-->(CN) [pi]*-back donation and gives rise to the first example of a Co-carbyne complex. The reactivity and electronic structure are presented for K2[Cp*Co≡CNArTripp2] and it is concluded that this reactive dianion behaves as a potent metal based nucleophile and source of [Cp*Co(CNR)]2- for a number of bond activation process.
Book Synopsis Bio-inspired First-row Transition Metal Complexes for Small Molecule Activation by : Yun Ji Park
Download or read book Bio-inspired First-row Transition Metal Complexes for Small Molecule Activation written by Yun Ji Park and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Electronic Tunings in Biomimetic Iron Complexes for Small Molecule Activation by : Teera Chantarojsiri
Download or read book Electronic Tunings in Biomimetic Iron Complexes for Small Molecule Activation written by Teera Chantarojsiri and published by . This book was released on 2015 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Atom and Group Transfer Reactions Involving High-valent Iron Complexes by : Yong Li
Download or read book Atom and Group Transfer Reactions Involving High-valent Iron Complexes written by Yong Li and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Iron enzymes play critical roles in biological oxidation reactions by utilizing highly reactive high-valent iron intermediates, such as FeIV=O, FeV(O)(OH), and FeIV=NR species, for catalytic reactions. These intermediates exhibit remarkable catalytic behavior with high reactivities and high regio- and stereospecificity in various biochemical reactions. Understanding these metal intermediates is crucial not only for replicating their activity but also for discovering new synthetic possibilities in chemical synthesis. To address the challenge of comprehending high-valent iron intermediates in biology, chemists have developed a number of bio-inspired functional models that exhibit a diverse range of catalytic properties. The main objective of this thesis is to examine the functional mimicry of mononuclear non-heme active sites in iron enzymes, specifically targeting FeIV=O, FeV(O)(OH) and FeIV=NR intermediates. Chapter 1 provides an introduction to active sites of iron enzymes in biological systems and related bio-inspired models utilizing iron complexes. Chapter 2 relates to Papers I and IV. Paper I describes the syntheses and characterizations of four new FeIV=O complexes based on new ligands with minor steric restriction. The reactivity of these complexes in C-H activation and O-atom transfer reactions has been investigated in detail. As the ligands include negligible steric restrictions, the reactivity differences between these FeIV=O complexes are attributed to the electronic properties of the ligands. On the other hand, Paper IV provides an example of a ligand framework where the steric restrictions of the specific ligand dictate the substrate accessibility. Chapter 3 relates to Paper II and gives a comparative study on the structure and reactivity patterns of a new FeIV=NR complex versus its FeIV=O congener. Chapter 4 relates to Paper III and studies the epoxidation of alkenes by two mononuclear non-heme FeIV=O complexes based on ligands with different electron-donating properties. The catalysis and kinetics studies shed light on the influence of electron-donating properties on the reactivity and mechanism of alkene epoxidation. This research provides insights into the influence exerted by ligand environments on the reactivities of FeIV=O, FeV(O)(OH) and FeIV=NR complexes. The study may contribute to the development of new, highly active catalysts for important oxidation reactions.
Book Synopsis Electronic Structure and Reactivity of Transition Metal Complexes Incorporating Pro-radical Bis-phenoxide Ligands by : Ryan Michael Clarke
Download or read book Electronic Structure and Reactivity of Transition Metal Complexes Incorporating Pro-radical Bis-phenoxide Ligands written by Ryan Michael Clarke and published by . This book was released on 2018 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transition metal complexes with pro-radical ligands have received considerable research attention due to their interesting electronic structures, photophysical properties, and applications in catalysis. The relative ordering of metal and ligand frontier orbitals in a complex incorporating pro-radical ligands dictates whether oxidation/reduction occurs at the metal centre or at the ligand. Many metalloenzymes couple redox events at multiple metal centres or between metals and pro-radical ligands to facilitate multielectron chemistry. Owing to the simplicity of the active sites, many structural and functional models have been studied. One class of pro-radical ligand that has been investigated extensively are bis-imine bis-phenoxide ligands (i.e. salen) due to their highly modular syntheses. In this thesis, projects related to the synthesis, electronic structure, and reactivity of mono and bimetallic complexes incorporating the salen framework are explored. Chapter 2 presents a systematic investigation of the effects of geometry on the electronic structure of four bis-oxidized bimetallic Ni salen species. The tunability of their intense intervalence charge transfer (IVCT) transitions in the near infrared (NIR) by nearly 400 nm due to exciton coupling in the excited states is described. For the first time, this study demonstrates the applicability of exciton coupling to ligand radical systems absorbing in the NIR region. Chapter 3 investigates the ground-state electronic structure of a bis-oxidized Co dimer. Enhanced metal participation to the singly occupied molecular orbitals results in both high spin Co(III) and Co(II)-L• character in the ground state, and no observable band splitting in the NIR due to exciton coupling. Finally, Chapter 4 describes a series of oxidized nitridomanganese(V) salen complexes with different para ring substituents (R = CF3, tBu, and NMe2), demonstrating that nitride activation is dictated by remote ligand electronics. Upon one-electron oxidation, electron deficient ligands afford a Mn(VI) species and nitride activation, whereas an electron-rich ligand results in ligand based oxidation and resistance to N coupling of the nitrides. This study highlights the alternative reactivity pathways that pro-radical ligands impose on metal complexes and represents a key step in the use of NH3 as a hydrogen storage medium. The results presented herein provide a starting point for further efforts in reactivity with the salen platform.
Book Synopsis Electronic Unsaturation of Organometallic Complexes Imparted by Sterically Demanding Ligands by : Derek M Isrow
Download or read book Electronic Unsaturation of Organometallic Complexes Imparted by Sterically Demanding Ligands written by Derek M Isrow and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The reactivity of bulky ligands with various transition metal complexes was studied to better understand the nature of organometallic electronic unsaturation and the role this plays in small molecule activation. A bulky stannyl hydride, tBu3SnH, was synthesized by a revised procedure that is far more facile and reproducible. This sterically encumbered ligand was shown to oxidatively add to a broad range of transition metal complexes, particularly those displaying carbonyl ligands, in greatly differing manners. Reaction of tBu3SnH with Ni(COD)2 and tBuNC was found to yield the mononuclear complex Ni(SntBu3)2(tBuNC)3. This compound possesses photochemical reactivity, most likely attributable to the massive steric bulk surrounding the Ni center, and generates electronically unsaturated metal centered radicals upon photolysis. This complex and its photochemical products were studied from both experimental and spectroscopic aspects. The stable organic radical TEMPO was also reacted with Ni(COD)2 to afford the unsaturated square planar complex Ni(TEMPO)2 which was studied both experimentally and spectroscopically. This deceivingly simple compound displays a wide spectrum of complicated reactivity and small molecule activation which may be utilized in future catalysis.
Book Synopsis Synthesis and Reactivity of Main Group Complexes for Applications in Small Molecule Activation by : Minh Tho Nguyen
Download or read book Synthesis and Reactivity of Main Group Complexes for Applications in Small Molecule Activation written by Minh Tho Nguyen and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The work described in this thesis is focused on the preparation of a series of novel main group complexes, featuring unusual structural and bonding situations, and the study of their reactivity toward small molecules. The new zinc complexes dimphZnBu (V-2) and dimphZnCl2Li(THF)3 (V-3), supported by a diiminophenyl (dimph) ligand were prepared. The reaction of complex V-3 with LiHBEt3 resulted in hydride transfer to the C=N imine group to give an unusual zinc dimer (V-7). The latter transformation occurs via formation of compound (ɳ1(C),ĸ1(N)- 2,6-(2,6-iPr2C6H3N=CH)2C6H3)2Zn (V-5) which can be also accessed by reduction of V-7 with KC8. Diiminophenyl (dimph) proved to be an excellent ligand platform to stabilise a low-valent phosphorus centre. The resultant compound dimphP (VI-2), which can be rationalised as an imino-stabilised phosphinidene or benzoazaphopshole, shows remarkable chemical stability toward water and oxygen. VI-2 reacts with excess strong acid HCl to generate the P(III) chloride (dimHph)PCl (VI-6). Surprisingly, substitution of the chloride under some nucleophilic (KOBut) and electrophilic conditions (Me3SiOTf) regenerates the parent compound VI-2 by proton removal from the weakly acidic CH2N position. A related species (dimH2ph)P (VI-10) is produced upon thermal rearrangement of the hydride (dimHph)PH (VI-9). The molecular structure and reactivity of compounds VI-2 and other related compounds are also discussed. The reduction of the O,C,O-chelated phosphorus (III) chloride (VI-16) ( O,C,O = 2,6-bis[(2,6-diisopropyl)phenoxyl]phenyl) with KC8 or PMe3 resulted in the formation of a cyclic three-membered phosphorus compound (VI-18). The intermediacy of phosphinidene VI-17 was confirmed by trapping experiments and a VT 31P{1H} NMR study. The reaction of in-situ generated phosphinidene with either PhSiH3 or HBpin resulted in the formation of an unprecedented phosphine (VI-23). The treatment of VI-16 with two equivalents of DippNHC carbene led to ArP(Cl)NHC product (VI-24). The germylone dimNHCGe (dimNHC = diimino N-Heterocyclic Carbene, VII-8) was successfully prepared by the reduction of germanium cation (VII-7) with KC8. The molecular structure of VII-8 was unambiguously established, using NMR spectroscopy and single-crystal X-ray diffraction analysis. The reactivity of VII-8 was investigated. VII-8 is inactive towards butadiene but undergoes an oxidative cyclization with tetrachloro-o-benzoquinone to give a tetragermanium derivative. VII-8 undergoes oxidation addition of CH3I and PhI, followed by an unusual migration of the Me and Ph groups from germanium to the carbene ligand. Related chemistry takes place upon protonation with dry HCl, which results in the migration of the hydride to the carbene ligand.
Book Synopsis Comprehensive Inorganic Chemistry II by :
Download or read book Comprehensive Inorganic Chemistry II written by and published by Newnes. This book was released on 2013-07-23 with total page 7694 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive Inorganic Chemistry II, Nine Volume Set reviews and examines topics of relevance to today’s inorganic chemists. Covering more interdisciplinary and high impact areas, Comprehensive Inorganic Chemistry II includes biological inorganic chemistry, solid state chemistry, materials chemistry, and nanoscience. The work is designed to follow on, with a different viewpoint and format, from our 1973 work, Comprehensive Inorganic Chemistry, edited by Bailar, Emeléus, Nyholm, and Trotman-Dickenson, which has received over 2,000 citations. The new work will also complement other recent Elsevier works in this area, Comprehensive Coordination Chemistry and Comprehensive Organometallic Chemistry, to form a trio of works covering the whole of modern inorganic chemistry. Chapters are designed to provide a valuable, long-standing scientific resource for both advanced students new to an area and researchers who need further background or answers to a particular problem on the elements, their compounds, or applications. Chapters are written by teams of leading experts, under the guidance of the Volume Editors and the Editors-in-Chief. The articles are written at a level that allows undergraduate students to understand the material, while providing active researchers with a ready reference resource for information in the field. The chapters will not provide basic data on the elements, which is available from many sources (and the original work), but instead concentrate on applications of the elements and their compounds. Provides a comprehensive review which serves to put many advances in perspective and allows the reader to make connections to related fields, such as: biological inorganic chemistry, materials chemistry, solid state chemistry and nanoscience Inorganic chemistry is rapidly developing, which brings about the need for a reference resource such as this that summarise recent developments and simultaneously provide background information Forms the new definitive source for researchers interested in elements and their applications; completely replacing the highly cited first edition, which published in 1973
Book Synopsis Iron Catalysis in Organic Chemistry by : Bernd Plietker
Download or read book Iron Catalysis in Organic Chemistry written by Bernd Plietker and published by John Wiley & Sons. This book was released on 2008-09-08 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: This first comprehensive book to cover this exciting field also deals with the biological aspects, such as enzymes with iron. Following an introduction, this handy reference and handbook goes on to deal with reductions, oxidations of C, H- and C=C bonds, oxidative allylic oxygenation and amination, the oxidation of heteroatoms, cross coupling reactions, aromatic and nucleophilic substitutions, addition to carbonyl compounds, and cyclisations as well as ring opening reactions. The chapters are clearly classified according to the reaction type, allowing readers to quickly locate the desired information.
Book Synopsis Dissertation Abstracts International by :
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2002 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Iron Catalysis written by Bernd Plietker and published by Springer Science & Business Media. This book was released on 2011-01-05 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: Juan I. Padrón and Víctor S. Martín: Catalysis by means of Fe-based Lewis acids; Hiroshi Nakazawa*, Masumi Itazaki: Fe–H Complexes in Catalysis; Kristin Schröder, Kathrin Junge, Bianca Bitterlich, and Matthias Beller: Fe-catalyzed Oxidation Reactions of Olefins, Alkanes and Alcohols: Involvement of Oxo- and Peroxo Complexes; Chi-Ming Che, Cong-Ying Zhou, Ella Lai-Ming Wong: Catalysis by Fe=X Complexes (X=NR, CR2); René Peters, Daniel F. Fischer and Sascha Jautze: Ferrocene and Half Sandwich Complexes as Catalysts with Iron Participation; Markus Jegelka, Bernd Plietker: Catalysis by Means of Complex Ferrates.
Book Synopsis Metal Sites in Proteins and Models by : H.A.O. Hill
Download or read book Metal Sites in Proteins and Models written by H.A.O. Hill and published by Springer Science & Business Media. This book was released on 1999-04-01 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biological chemistry is a major frontier of inorganic chemistry. Three special volumes devoted to Metal Sites in Proteins and Models address the questions: how unusual ("entatic") are metal sites in metalloproteins and metalloenzymes compared to those in small coordination complexes? and if they are special, how do polypeptide chains and co-factors control this? The chapters deal with iron, with metal centres acting as Lewis acids, metals in phosphate enzymes, with vanadium, and with the wide variety of transition metal ions which act as redox centres. They illustrate in particular how the combined armoury of genetics and structure determination at the molecular level are providing unprecedented new tools for molecular engineering.
Book Synopsis Comprehensive Natural Products III by :
Download or read book Comprehensive Natural Products III written by and published by Elsevier. This book was released on 2020-07-22 with total page 4266 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive Natural Products III, Third Edition, Seven Volume Set updates and complements the previous two editions, including recent advances in cofactor chemistry, structural diversity of natural products and secondary metabolites, enzymes and enzyme mechanisms and new bioinformatics tools. Natural products research is a dynamic discipline at the intersection of chemistry and biology concerned with isolation, identification, structure elucidation, and chemical characteristics of naturally occurring compounds such as pheromones, carbohydrates, nucleic acids and enzymes. This book reviews the accumulated efforts of chemical and biological research to understand living organisms and their distinctive effects on health and medicine and to stimulate new ideas among the established natural products community. Provides readers with an in-depth review of current natural products research and a critical insight into the future direction of the field Bridges the gap in knowledge by covering developments in the field since the second edition published in 2010 Split into 7 sections on key topics to allow students, researchers and professionals to find relevant information quickly and easily Ensures that the knowledge within is easily understood by and applicable to a large audience
Book Synopsis Transition Metal-Dinitrogen Complexes by : Yoshiaki Nishibayashi
Download or read book Transition Metal-Dinitrogen Complexes written by Yoshiaki Nishibayashi and published by John Wiley & Sons. This book was released on 2019-05-06 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive book that explores nitrogen fixation by using transition metal-dinitrogen complexes Nitrogen fixation is one of the most prominent fields of research in chemistry. This book puts the focus on the development of catalytic ammonia formation from nitrogen gas under ambient reaction conditions that has been recently repowered by some research groups. With contributions from noted experts in the field, Transition Metal-Dinitrogen Complexes offers an important guide and comprehensive resource to the most recent research and developments on the topic of nitrogen fixation by using transition metal-dinitrogen. The book is filled with the information needed to understand the synthesis of transition metal-dinitrogen complexes and their reactivity. This important book: -Offers a resource for understanding nitrogen fixation chemistry that is essential for explosives, pharmaceuticals, dyes, and all forms of life -Includes the information needed for anyone interested in the field of nitrogen fixation by using transition metal-dinitrogen complexes -Contains state-of-the-art research on synthesis of transition metal-dinitrogen complexes and their reactivity in nitrogen fixation -Incorporates contributions from well-known specialists and experts with an editor who is an innovator in the field of dinitrogen chemistry Written for chemists and scientists with an interest in nitrogen fixation, Transition Metal-Dinitrogen Complexes is a must-have resource to the burgeoning field of nitrogen fixation by using transition metal-dinitrogen complexes.
Book Synopsis Spin States in Biochemistry and Inorganic Chemistry by : Marcel Swart
Download or read book Spin States in Biochemistry and Inorganic Chemistry written by Marcel Swart and published by John Wiley & Sons. This book was released on 2015-09-17 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: It has long been recognized that metal spin states play a central role in the reactivity of important biomolecules, in industrial catalysis and in spin crossover compounds. As the fields of inorganic chemistry and catalysis move towards the use of cheap, non-toxic first row transition metals, it is essential to understand the important role of spin states in influencing molecular structure, bonding and reactivity. Spin States in Biochemistry and Inorganic Chemistry provides a complete picture on the importance of spin states for reactivity in biochemistry and inorganic chemistry, presenting both theoretical and experimental perspectives. The successes and pitfalls of theoretical methods such as DFT, ligand-field theory and coupled cluster theory are discussed, and these methods are applied in studies throughout the book. Important spectroscopic techniques to determine spin states in transition metal complexes and proteins are explained, and the use of NMR for the analysis of spin densities is described. Topics covered include: DFT and ab initio wavefunction approaches to spin states Experimental techniques for determining spin states Molecular discovery in spin crossover Multiple spin state scenarios in organometallic reactivity and gas phase reactions Transition-metal complexes involving redox non-innocent ligands Polynuclear iron sulfur clusters Molecular magnetism NMR analysis of spin densities This book is a valuable reference for researchers working in bioinorganic and inorganic chemistry, computational chemistry, organometallic chemistry, catalysis, spin-crossover materials, materials science, biophysics and pharmaceutical chemistry.
