This document contains information about mass spectrometry techniques including electrospray ionization mass spectrometry (ESI-MS) and electron transfer dissociation (ETD) applied to analyze peptide toxins from cone snail venom. ESI-MS was used to obtain mass measurements of intact peptides and some sequence information through fragmentation. ETD was later used to gain additional sequence coverage, resolving the identity of the N-terminal residues as serine-valine (S-V).
This document reports on research measuring the strength of silicon-hydrogen bonds in various silane compounds using photoacoustic calorimetry. The main findings are:
1) Silicon-hydrogen bond strengths are significantly weakened by the successive substitution of silyl groups, with the bond in tris(trimethylsilyl)silane having one of the weakest bond strengths measured at 79.0 kcal/mol.
2) Steric effects and radical stabilization may contribute to the weakening of the silicon-hydrogen bond from additional silyl substitutions, though the exact origin is unclear.
3) The weak silicon-hydrogen bond in tris(trimethylsilyl)silane
This document describes the stereocontrolled synthesis of the alkaloids quinine and quinidine. It begins with the synthesis of a disubstituted cyclopentene which is oxidatively cleaved and converted to a piperidine ring. This piperidine is then condensed with a quinoline part to form an olefin precursor to quinine. Various transformations are performed on this precursor to ultimately obtain quinine. A similar process is used to synthesize quinidine. The synthesis allows for flexible modification of the structural backbones of these important alkaloids.
Chromcol Instruments is an Indian company that sells and services analytical instruments for the pharmaceutical and chemical industries, offering quality service, instrument regeneration, and data loggers, with the mission of gaining and retaining customers through prompt, satisfactory support. The company has over 10 years of experience in instrument sales, service, and regeneration of HPLC columns to restore efficiency. Chromcol Instruments represents several reputable OEMs and has the expertise to regenerate commonly used HPLC columns with a high success rate of 98.4%.
This document provides an overview of high performance liquid chromatography (HPLC). It discusses the history of chromatography beginning with Mikhail Semenovich Tswett's 1903 presentation and separation of chlorophyll pigments. The basics of chromatography are explained, including the interactions between a sample's components and two phases that result in separation. Key aspects of HPLC systems and operations are also summarized such as pumps, detectors, columns, method development techniques, and parameters for method validation.
The importance of clean drinking water is recognized worldwide. In the U.S., the Environmental Protection Agency (EPA) has established Maximum Contamination Limits (MCL) for monitoring toxic contaminants that may cause adverse health effects. Other ions, such as chloride and sulfate are monitored for aesthetic characteristics under the U.S. National Secondary Drinking Water Standards guidelines. Similar regulations for clean drinking water have been implemented in other industrialized countries. Ion Chromatography (IC) methods have been approved for compliance monitoring including U.S. EPA 300.0 in 1993. Learn about using ion chromatography for the determination of inorganic anions, perchlorate and chromate for compliance monitoring according to U.S. EPA Methods 300.0, 314 and 218.6.
This document summarizes a presentation on chiral separations by HPLC. It discusses chirality and why it is important for drugs. It describes different types of chiral stationary phases used for chiral chromatography, including polysaccharide and immobilized polysaccharide phases. The document provides examples of method development on these phases under normal phase, polar, and reversed phase conditions. It discusses factors that influence separations like solvents, additives, and injection solvents. The document demonstrates chiral separations of several drug compounds under various chromatographic conditions.
HPLC is a type of liquid chromatography that can separate mixtures of chemicals. It works by pumping a pressurized liquid solvent (mobile phase) through a column containing a solid material (stationary phase). Samples are injected and the different compounds interact differently with the phases, causing them to elute from the column at different retention times, allowing separation. HPLC has advantages over other methods like higher separation efficiency, reproducibility, and ability to analyze a wide range of compounds dissolved in liquid. It is used in various fields like medicine, food, environment, and industry.
This document provides an overview of high performance liquid chromatography (HPLC) presented by Ravi Pratap Pulla. It introduces HPLC and its history. Key topics covered include HPLC components like columns and systems. Applications to pharmaceutical analysis are discussed. The document also reviews some basic HPLC terminology and concepts.
This document reports on research measuring the strength of silicon-hydrogen bonds in various silane compounds using photoacoustic calorimetry. The main findings are:
1) Silicon-hydrogen bond strengths are significantly weakened by the successive substitution of silyl groups, with the bond in tris(trimethylsilyl)silane having one of the weakest bond strengths measured at 79.0 kcal/mol.
2) Steric effects and radical stabilization may contribute to the weakening of the silicon-hydrogen bond from additional silyl substitutions, though the exact origin is unclear.
3) The weak silicon-hydrogen bond in tris(trimethylsilyl)silane
This document describes the stereocontrolled synthesis of the alkaloids quinine and quinidine. It begins with the synthesis of a disubstituted cyclopentene which is oxidatively cleaved and converted to a piperidine ring. This piperidine is then condensed with a quinoline part to form an olefin precursor to quinine. Various transformations are performed on this precursor to ultimately obtain quinine. A similar process is used to synthesize quinidine. The synthesis allows for flexible modification of the structural backbones of these important alkaloids.
Chromcol Instruments is an Indian company that sells and services analytical instruments for the pharmaceutical and chemical industries, offering quality service, instrument regeneration, and data loggers, with the mission of gaining and retaining customers through prompt, satisfactory support. The company has over 10 years of experience in instrument sales, service, and regeneration of HPLC columns to restore efficiency. Chromcol Instruments represents several reputable OEMs and has the expertise to regenerate commonly used HPLC columns with a high success rate of 98.4%.
This document provides an overview of high performance liquid chromatography (HPLC). It discusses the history of chromatography beginning with Mikhail Semenovich Tswett's 1903 presentation and separation of chlorophyll pigments. The basics of chromatography are explained, including the interactions between a sample's components and two phases that result in separation. Key aspects of HPLC systems and operations are also summarized such as pumps, detectors, columns, method development techniques, and parameters for method validation.
The importance of clean drinking water is recognized worldwide. In the U.S., the Environmental Protection Agency (EPA) has established Maximum Contamination Limits (MCL) for monitoring toxic contaminants that may cause adverse health effects. Other ions, such as chloride and sulfate are monitored for aesthetic characteristics under the U.S. National Secondary Drinking Water Standards guidelines. Similar regulations for clean drinking water have been implemented in other industrialized countries. Ion Chromatography (IC) methods have been approved for compliance monitoring including U.S. EPA 300.0 in 1993. Learn about using ion chromatography for the determination of inorganic anions, perchlorate and chromate for compliance monitoring according to U.S. EPA Methods 300.0, 314 and 218.6.
This document summarizes a presentation on chiral separations by HPLC. It discusses chirality and why it is important for drugs. It describes different types of chiral stationary phases used for chiral chromatography, including polysaccharide and immobilized polysaccharide phases. The document provides examples of method development on these phases under normal phase, polar, and reversed phase conditions. It discusses factors that influence separations like solvents, additives, and injection solvents. The document demonstrates chiral separations of several drug compounds under various chromatographic conditions.
HPLC is a type of liquid chromatography that can separate mixtures of chemicals. It works by pumping a pressurized liquid solvent (mobile phase) through a column containing a solid material (stationary phase). Samples are injected and the different compounds interact differently with the phases, causing them to elute from the column at different retention times, allowing separation. HPLC has advantages over other methods like higher separation efficiency, reproducibility, and ability to analyze a wide range of compounds dissolved in liquid. It is used in various fields like medicine, food, environment, and industry.
This document provides an overview of high performance liquid chromatography (HPLC) presented by Ravi Pratap Pulla. It introduces HPLC and its history. Key topics covered include HPLC components like columns and systems. Applications to pharmaceutical analysis are discussed. The document also reviews some basic HPLC terminology and concepts.
Evgeny nikolaev proteomics of body liquids as a source for potential methods ...igorod
The document discusses using mass spectrometry to analyze body fluids like urine, saliva, and exhaled breath condensate for medical diagnostics and biomarker discovery. It describes creating databases of accurate mass tags and retention times from mass spec analyses of peptides and proteins in body fluids to enable fast identification. Biomarkers found for diseases like COPD, pneumonia and changes after lung transplantation are mentioned.
The document discusses the synthesis of heterobimetallic NHC ligand based complexes and their catalytic applications. It describes various methods for synthesizing these complexes using triazolylidene and imidazolylidene ligands to link two metal centers. Testing of the complexes showed that combining two metals into a single ligand framework often provides better catalytic performance than using a mixture of homometallic complexes. The binding site of the metals, whether as N^N chelate or NHC, was also found to influence catalytic activity.
Text mining to produce large chemistry datasets for community accessValery Tkachenko
While in an ideal world all data would be deposited by the producing scientist directly into a database, in the real-world most chemical data is instead presented in a form designed for human rather than machine consumption. Text mining has the potential to extract this data back into a computer understandable form. As all United States patents are available free of charge they make the perfect corpus for extracting a large number of experimental properties of compounds, and chemical reactions.
We report on our text-mining activities to extract millions of textual NMR spectra, hundreds of thousands of physicochemical properties (with their associated compounds) and over a million chemical reactions. All extracted results are to be deposited into online databases allowing the community to benefit from the results of this work.
Using Mestrelab Research’s MNova product we have converted the textual NMR spectra to graphical spectra, and validated each spectrum against its associated chemical structure so as to detect cases where the NMR spectrum could not be produced by the associated structure.
In the case of melting points the resultant dataset, of over a quarter of a million melting compound/temperature relationships, is the largest public dataset the authors are aware of. We have used this dataset to produce a predictive model with results comparable to those of manually curated datasets. Our experiences with modelling this data has demonstrated that we are working at the edge of current algorithmic and computing capabilities for predictive model building, with the resultant matrix containing over 200 billion descriptors. The melting point model and the data it was derived from are available freely from http://www.ochem.eu.
The document provides information about various 2D NMR techniques including HETCOR, INADEQUATE, and guidelines for interpreting NMR data. It discusses how HETCOR spectra show carbon-proton coupling and provides an example spectrum of 2-methyl-3-pentanone. INADEQUATE is introduced as a technique for determining carbon-carbon coupling constants using natural abundance. Examples of NMR data interpretation are also provided for small molecules such as methane, benzene, adenine, cytosine, naphthalene, and quinine to demonstrate analyzing chemical shifts and spin multiplicity.
Si-Imidazole-HSO4 Functionalized Magnetic Fe3O4 Nanoparticles as an Efficient...Iranian Chemical Society
An efficient and simple method for the preparation of Si-Imidazole-HSO4 functionalized magnetic Fe3O4 nanoparticles (Si-Im-HSO4 MNPs) and used as an efficient and reusable magnetic catalysts for the regioselective ring opening of epoxides under green conditions in water. This catalyst was used for the ring opening of epoxide corresponding to the thiocyanohydrins and azidohydrines. Compared to the classical ring opening of epoxides, this new method consistently has the advantage of excellent yields, short reaction times, and methodological simplicity.
Aaa qualitative and dft analysis of endiynes for isha slideshareDr Robert Craig PhD
Students used computational chemistry methods like DFT and Gaussian 09 to study the properties of 8,10,11 trihydroxy- 9- oxoBicyclo(7:2:2)undec 2- yne,4-ene,6-yne (C11H5O4). They optimized the geometry, calculated vibrational frequencies using B3LYP/6-311++(2p,3d) basis sets, and compared the results to experimental NMR and Raman spectra. Key peaks in the IR and Raman spectra matched calculations, validating the computational analysis of this enediyne compound.
This doctoral thesis presentation summarizes research on the transmetallation mechanisms of gadolinium complexes. The work studied newly developed contrast agents for magnetic resonance imaging to improve safety and efficiency. Physicochemical properties of macrocyclic ligands and their gadolinium complexes were characterized using potentiometric titrations, UV-Vis spectroscopy, and NMR spectroscopy to determine protonation states and kinetic inertness towards demetallation. The goal was to better understand transmetallation mechanisms in order to develop safer and more effective MRI contrast agents.
This document summarizes a doctoral thesis that examines how irradiation can help prevent ischemia and reperfusion injury. The thesis includes four papers that study the effects of irradiation on energy metabolism in rat skeletal muscle and hearts, as well as reactive oxygen species and nitric oxide in human monocytes. The studies find that irradiation helps preserve high-energy phosphates like ATP and phosphocreatine during ischemia, improves energetic recovery after ischemia/reperfusion, and decreases reactive oxygen species while increasing nitric oxide in monocytes. Overall, the thesis demonstrates the protective effects of irradiation against ischemia/reperfusion injury in various experimental models.
The document discusses quantum criticality in biomolecules and how quantum effects may have played a role in the origins and evolution of life. It describes how molecules at the critical point between order and disorder can avoid decoherence the longest, providing an evolutionary advantage. Several naturally occurring biomolecules are found to exhibit properties of quantum criticality through analyses of their wave functions, energy level statistics, and molecular graphs. Receptors are also analyzed and found to position critical biomolecules like adenosine and testosterone in a way that preserves quantum coherence during signaling.
This document summarizes the revised NMR data for the alkaloid incartine isolated from Galanthus elwesii. The researchers revised the previously reported NMR data for incartine through 2D NMR experiments. They also isolated four other alkaloids from G. elwesii: hordenine, lycorine, 8-O-demethylhomolycorine, and hippeastrine. In vitro bioactivity studies showed that incartine had no remarkable antiviral or cytotoxic activity and only weakly inhibited acetylcholinesterase.
1) 1H NMR spectroscopy is a technique used to elucidate the structure of organic compounds by determining the number and environment of protons in a molecule.
2) The principle behind 1H NMR is that proton nuclei have a spin and when placed in a magnetic field will absorb radiofrequency energy, appearing as signals in the NMR spectrum.
3) The chemical shift of 1H NMR signals provides information about the electronic environment and bonding of protons. Signals are referenced to TMS and appear in different regions of the spectrum.
The document discusses the interpretation of proton nuclear magnetic resonance (NMR) spectroscopy. It explains how NMR works and the information that can be obtained from NMR spectra, including the number of signals indicating different types of hydrogen atoms, peak integration revealing hydrogen ratios, and chemical shifts indicating electronic environments. It also covers spin-spin splitting patterns from neighboring hydrogen atoms. The document uses examples to illustrate concepts like chemically equivalent and non-equivalent protons, diastereotopic and enantiotopic protons, and interpretation of peak area, chemical shifts, and spin-spin splitting. It concludes that NMR spectroscopy is a useful qualitative tool for structural elucidation in pharmaceutical, chemical, and fertilizer industries.
This document provides an introduction and overview of C-13 nuclear magnetic resonance (NMR) spectroscopy. It discusses the basic principles of NMR, including nuclear spin, resonance frequency, chemical shifts, spin relaxation, scalar coupling, and other concepts. Examples of typical chemical shift ranges are given for different types of carbon environments. Predictions of chemical shifts are demonstrated using known substituent effects. Solvent chemical shift references are also provided.
Introduction To Proton NMR and InterpretationAamir Malik
This document provides an overview of proton nuclear magnetic resonance (1H NMR) spectroscopy. It discusses the basic principles of NMR, including how protons absorb radiofrequency energy in a magnetic field. The document describes NMR instrumentation and the relaxation and chemical shift phenomena observed in spectra. It also explains how spectral signals are split based on neighboring nuclei. Finally, the document provides examples of 1H NMR spectra for various molecules and interpretations of the number of signals, positions, intensities, and splitting patterns.
UCSD NANO 266 Quantum Mechanical Modelling of Materials and Nanostructures is a graduate class that provides students with a highly practical introduction to the application of first principles quantum mechanical simulations to model, understand and predict the properties of materials and nano-structures. The syllabus includes: a brief introduction to quantum mechanics and the Hartree-Fock and density functional theory (DFT) formulations; practical simulation considerations such as convergence, selection of the appropriate functional and parameters; interpretation of the results from simulations, including the limits of accuracy of each method. Several lab sessions provide students with hands-on experience in the conduct of simulations. A key aspect of the course is in the use of programming to facilitate calculations and analysis.
This document summarizes the synthesis and characterization of a new potassium complex of phthiocol, a vitamin K3 analog. Key findings include:
1) Phthiocol binds to two potassium ions through its oxygen atoms, forming a polymeric chain structure.
2) Single crystal X-ray diffraction reveals hydrogen bonding interactions between coordinated water molecules, forming water channels along the crystal structure.
3) NMR and electrochemical studies provide evidence that the complex exists as a naphthosemiquinone, with the potential for a one-electron reduction to the catechol form.
1. The document discusses methods for elucidating molecular structures, including determination of unsaturation number (DBE/UN), spectroscopy techniques like UV-Vis, IR, mass spectrometry, NMR (1H and 13C), and DEPT.
2. It provides details on interpreting 1H NMR spectra, including number of signals, chemical shifts, integration, and splitting patterns. It also discusses interpreting 13C NMR spectra based on number of signals, chemical shifts, and DEPT experiments.
3. The goal is to obtain information about the types of carbons (CH3, CH2, CH, C) in a molecule from analysis of 1H NMR, 13C NMR, and DEPT spectra.
This document summarizes the potential benefits of low-level laser therapy (LLLT) for anti-aging and healing applications. It discusses how LLLT may work by increasing ATP production and reducing oxidative stress at the mitochondrial level. It also reviews evidence that LLLT can reduce inflammation, promote wound healing, and help with conditions like arthritis, brain injuries, and hair regrowth through photobiomodulation effects on cell signaling and gene expression. The document examines key parameters for effective LLLT dosing and provides examples of clinical studies supporting its use.
This document summarizes key concepts in quantum biology and quantum criticality. It discusses how:
1) Molecules like adenosine and testosterone may exhibit quantum critical behavior when interacting with cellular receptors, with their wavefunctions showing multifractal properties.
2) Analyzing the level spacing statistics of biomolecules provides evidence that many are in a critical state between delocalized and localized behavior.
3) Quantum criticality could provide an evolutionary advantage by allowing molecules to avoid decoherence and explore more combinatorial possibilities during evolution.
This document summarizes the laboratory detection and characterization of eight new carbon chain molecules. Key findings include:
- Cyanopolyynes HC11N and HC13N were detected in a supersonic molecular beam using Fourier transform microwave spectroscopy. Spectroscopic constants were derived from measured rotational transition frequencies.
- Carbon chain radicals C7H, C8H, C9H, and C11H were produced in a gas discharge and detected using Fourier transform microwave and millimeter-wave absorption spectroscopy. Spectroscopic constants were derived.
- Cumulene carbenes H2C5H2 and H2C6H2 were detected in a gas discharge using Fourier transform microwave spectroscopy. Spectroscopic
Communicating effectively and consistently with students can help them feel at ease during their learning experience and provide the instructor with a communication trail to track the course's progress. This workshop will take you through constructing an engaging course container to facilitate effective communication.
Evgeny nikolaev proteomics of body liquids as a source for potential methods ...igorod
The document discusses using mass spectrometry to analyze body fluids like urine, saliva, and exhaled breath condensate for medical diagnostics and biomarker discovery. It describes creating databases of accurate mass tags and retention times from mass spec analyses of peptides and proteins in body fluids to enable fast identification. Biomarkers found for diseases like COPD, pneumonia and changes after lung transplantation are mentioned.
The document discusses the synthesis of heterobimetallic NHC ligand based complexes and their catalytic applications. It describes various methods for synthesizing these complexes using triazolylidene and imidazolylidene ligands to link two metal centers. Testing of the complexes showed that combining two metals into a single ligand framework often provides better catalytic performance than using a mixture of homometallic complexes. The binding site of the metals, whether as N^N chelate or NHC, was also found to influence catalytic activity.
Text mining to produce large chemistry datasets for community accessValery Tkachenko
While in an ideal world all data would be deposited by the producing scientist directly into a database, in the real-world most chemical data is instead presented in a form designed for human rather than machine consumption. Text mining has the potential to extract this data back into a computer understandable form. As all United States patents are available free of charge they make the perfect corpus for extracting a large number of experimental properties of compounds, and chemical reactions.
We report on our text-mining activities to extract millions of textual NMR spectra, hundreds of thousands of physicochemical properties (with their associated compounds) and over a million chemical reactions. All extracted results are to be deposited into online databases allowing the community to benefit from the results of this work.
Using Mestrelab Research’s MNova product we have converted the textual NMR spectra to graphical spectra, and validated each spectrum against its associated chemical structure so as to detect cases where the NMR spectrum could not be produced by the associated structure.
In the case of melting points the resultant dataset, of over a quarter of a million melting compound/temperature relationships, is the largest public dataset the authors are aware of. We have used this dataset to produce a predictive model with results comparable to those of manually curated datasets. Our experiences with modelling this data has demonstrated that we are working at the edge of current algorithmic and computing capabilities for predictive model building, with the resultant matrix containing over 200 billion descriptors. The melting point model and the data it was derived from are available freely from http://www.ochem.eu.
The document provides information about various 2D NMR techniques including HETCOR, INADEQUATE, and guidelines for interpreting NMR data. It discusses how HETCOR spectra show carbon-proton coupling and provides an example spectrum of 2-methyl-3-pentanone. INADEQUATE is introduced as a technique for determining carbon-carbon coupling constants using natural abundance. Examples of NMR data interpretation are also provided for small molecules such as methane, benzene, adenine, cytosine, naphthalene, and quinine to demonstrate analyzing chemical shifts and spin multiplicity.
Si-Imidazole-HSO4 Functionalized Magnetic Fe3O4 Nanoparticles as an Efficient...Iranian Chemical Society
An efficient and simple method for the preparation of Si-Imidazole-HSO4 functionalized magnetic Fe3O4 nanoparticles (Si-Im-HSO4 MNPs) and used as an efficient and reusable magnetic catalysts for the regioselective ring opening of epoxides under green conditions in water. This catalyst was used for the ring opening of epoxide corresponding to the thiocyanohydrins and azidohydrines. Compared to the classical ring opening of epoxides, this new method consistently has the advantage of excellent yields, short reaction times, and methodological simplicity.
Aaa qualitative and dft analysis of endiynes for isha slideshareDr Robert Craig PhD
Students used computational chemistry methods like DFT and Gaussian 09 to study the properties of 8,10,11 trihydroxy- 9- oxoBicyclo(7:2:2)undec 2- yne,4-ene,6-yne (C11H5O4). They optimized the geometry, calculated vibrational frequencies using B3LYP/6-311++(2p,3d) basis sets, and compared the results to experimental NMR and Raman spectra. Key peaks in the IR and Raman spectra matched calculations, validating the computational analysis of this enediyne compound.
This doctoral thesis presentation summarizes research on the transmetallation mechanisms of gadolinium complexes. The work studied newly developed contrast agents for magnetic resonance imaging to improve safety and efficiency. Physicochemical properties of macrocyclic ligands and their gadolinium complexes were characterized using potentiometric titrations, UV-Vis spectroscopy, and NMR spectroscopy to determine protonation states and kinetic inertness towards demetallation. The goal was to better understand transmetallation mechanisms in order to develop safer and more effective MRI contrast agents.
This document summarizes a doctoral thesis that examines how irradiation can help prevent ischemia and reperfusion injury. The thesis includes four papers that study the effects of irradiation on energy metabolism in rat skeletal muscle and hearts, as well as reactive oxygen species and nitric oxide in human monocytes. The studies find that irradiation helps preserve high-energy phosphates like ATP and phosphocreatine during ischemia, improves energetic recovery after ischemia/reperfusion, and decreases reactive oxygen species while increasing nitric oxide in monocytes. Overall, the thesis demonstrates the protective effects of irradiation against ischemia/reperfusion injury in various experimental models.
The document discusses quantum criticality in biomolecules and how quantum effects may have played a role in the origins and evolution of life. It describes how molecules at the critical point between order and disorder can avoid decoherence the longest, providing an evolutionary advantage. Several naturally occurring biomolecules are found to exhibit properties of quantum criticality through analyses of their wave functions, energy level statistics, and molecular graphs. Receptors are also analyzed and found to position critical biomolecules like adenosine and testosterone in a way that preserves quantum coherence during signaling.
This document summarizes the revised NMR data for the alkaloid incartine isolated from Galanthus elwesii. The researchers revised the previously reported NMR data for incartine through 2D NMR experiments. They also isolated four other alkaloids from G. elwesii: hordenine, lycorine, 8-O-demethylhomolycorine, and hippeastrine. In vitro bioactivity studies showed that incartine had no remarkable antiviral or cytotoxic activity and only weakly inhibited acetylcholinesterase.
1) 1H NMR spectroscopy is a technique used to elucidate the structure of organic compounds by determining the number and environment of protons in a molecule.
2) The principle behind 1H NMR is that proton nuclei have a spin and when placed in a magnetic field will absorb radiofrequency energy, appearing as signals in the NMR spectrum.
3) The chemical shift of 1H NMR signals provides information about the electronic environment and bonding of protons. Signals are referenced to TMS and appear in different regions of the spectrum.
The document discusses the interpretation of proton nuclear magnetic resonance (NMR) spectroscopy. It explains how NMR works and the information that can be obtained from NMR spectra, including the number of signals indicating different types of hydrogen atoms, peak integration revealing hydrogen ratios, and chemical shifts indicating electronic environments. It also covers spin-spin splitting patterns from neighboring hydrogen atoms. The document uses examples to illustrate concepts like chemically equivalent and non-equivalent protons, diastereotopic and enantiotopic protons, and interpretation of peak area, chemical shifts, and spin-spin splitting. It concludes that NMR spectroscopy is a useful qualitative tool for structural elucidation in pharmaceutical, chemical, and fertilizer industries.
This document provides an introduction and overview of C-13 nuclear magnetic resonance (NMR) spectroscopy. It discusses the basic principles of NMR, including nuclear spin, resonance frequency, chemical shifts, spin relaxation, scalar coupling, and other concepts. Examples of typical chemical shift ranges are given for different types of carbon environments. Predictions of chemical shifts are demonstrated using known substituent effects. Solvent chemical shift references are also provided.
Introduction To Proton NMR and InterpretationAamir Malik
This document provides an overview of proton nuclear magnetic resonance (1H NMR) spectroscopy. It discusses the basic principles of NMR, including how protons absorb radiofrequency energy in a magnetic field. The document describes NMR instrumentation and the relaxation and chemical shift phenomena observed in spectra. It also explains how spectral signals are split based on neighboring nuclei. Finally, the document provides examples of 1H NMR spectra for various molecules and interpretations of the number of signals, positions, intensities, and splitting patterns.
UCSD NANO 266 Quantum Mechanical Modelling of Materials and Nanostructures is a graduate class that provides students with a highly practical introduction to the application of first principles quantum mechanical simulations to model, understand and predict the properties of materials and nano-structures. The syllabus includes: a brief introduction to quantum mechanics and the Hartree-Fock and density functional theory (DFT) formulations; practical simulation considerations such as convergence, selection of the appropriate functional and parameters; interpretation of the results from simulations, including the limits of accuracy of each method. Several lab sessions provide students with hands-on experience in the conduct of simulations. A key aspect of the course is in the use of programming to facilitate calculations and analysis.
This document summarizes the synthesis and characterization of a new potassium complex of phthiocol, a vitamin K3 analog. Key findings include:
1) Phthiocol binds to two potassium ions through its oxygen atoms, forming a polymeric chain structure.
2) Single crystal X-ray diffraction reveals hydrogen bonding interactions between coordinated water molecules, forming water channels along the crystal structure.
3) NMR and electrochemical studies provide evidence that the complex exists as a naphthosemiquinone, with the potential for a one-electron reduction to the catechol form.
1. The document discusses methods for elucidating molecular structures, including determination of unsaturation number (DBE/UN), spectroscopy techniques like UV-Vis, IR, mass spectrometry, NMR (1H and 13C), and DEPT.
2. It provides details on interpreting 1H NMR spectra, including number of signals, chemical shifts, integration, and splitting patterns. It also discusses interpreting 13C NMR spectra based on number of signals, chemical shifts, and DEPT experiments.
3. The goal is to obtain information about the types of carbons (CH3, CH2, CH, C) in a molecule from analysis of 1H NMR, 13C NMR, and DEPT spectra.
This document summarizes the potential benefits of low-level laser therapy (LLLT) for anti-aging and healing applications. It discusses how LLLT may work by increasing ATP production and reducing oxidative stress at the mitochondrial level. It also reviews evidence that LLLT can reduce inflammation, promote wound healing, and help with conditions like arthritis, brain injuries, and hair regrowth through photobiomodulation effects on cell signaling and gene expression. The document examines key parameters for effective LLLT dosing and provides examples of clinical studies supporting its use.
This document summarizes key concepts in quantum biology and quantum criticality. It discusses how:
1) Molecules like adenosine and testosterone may exhibit quantum critical behavior when interacting with cellular receptors, with their wavefunctions showing multifractal properties.
2) Analyzing the level spacing statistics of biomolecules provides evidence that many are in a critical state between delocalized and localized behavior.
3) Quantum criticality could provide an evolutionary advantage by allowing molecules to avoid decoherence and explore more combinatorial possibilities during evolution.
This document summarizes the laboratory detection and characterization of eight new carbon chain molecules. Key findings include:
- Cyanopolyynes HC11N and HC13N were detected in a supersonic molecular beam using Fourier transform microwave spectroscopy. Spectroscopic constants were derived from measured rotational transition frequencies.
- Carbon chain radicals C7H, C8H, C9H, and C11H were produced in a gas discharge and detected using Fourier transform microwave and millimeter-wave absorption spectroscopy. Spectroscopic constants were derived.
- Cumulene carbenes H2C5H2 and H2C6H2 were detected in a gas discharge using Fourier transform microwave spectroscopy. Spectroscopic
Communicating effectively and consistently with students can help them feel at ease during their learning experience and provide the instructor with a communication trail to track the course's progress. This workshop will take you through constructing an engaging course container to facilitate effective communication.
Chapter wise All Notes of First year Basic Civil Engineering.pptxDenish Jangid
Chapter wise All Notes of First year Basic Civil Engineering
Syllabus
Chapter-1
Introduction to objective, scope and outcome the subject
Chapter 2
Introduction: Scope and Specialization of Civil Engineering, Role of civil Engineer in Society, Impact of infrastructural development on economy of country.
Chapter 3
Surveying: Object Principles & Types of Surveying; Site Plans, Plans & Maps; Scales & Unit of different Measurements.
Linear Measurements: Instruments used. Linear Measurement by Tape, Ranging out Survey Lines and overcoming Obstructions; Measurements on sloping ground; Tape corrections, conventional symbols. Angular Measurements: Instruments used; Introduction to Compass Surveying, Bearings and Longitude & Latitude of a Line, Introduction to total station.
Levelling: Instrument used Object of levelling, Methods of levelling in brief, and Contour maps.
Chapter 4
Buildings: Selection of site for Buildings, Layout of Building Plan, Types of buildings, Plinth area, carpet area, floor space index, Introduction to building byelaws, concept of sun light & ventilation. Components of Buildings & their functions, Basic concept of R.C.C., Introduction to types of foundation
Chapter 5
Transportation: Introduction to Transportation Engineering; Traffic and Road Safety: Types and Characteristics of Various Modes of Transportation; Various Road Traffic Signs, Causes of Accidents and Road Safety Measures.
Chapter 6
Environmental Engineering: Environmental Pollution, Environmental Acts and Regulations, Functional Concepts of Ecology, Basics of Species, Biodiversity, Ecosystem, Hydrological Cycle; Chemical Cycles: Carbon, Nitrogen & Phosphorus; Energy Flow in Ecosystems.
Water Pollution: Water Quality standards, Introduction to Treatment & Disposal of Waste Water. Reuse and Saving of Water, Rain Water Harvesting. Solid Waste Management: Classification of Solid Waste, Collection, Transportation and Disposal of Solid. Recycling of Solid Waste: Energy Recovery, Sanitary Landfill, On-Site Sanitation. Air & Noise Pollution: Primary and Secondary air pollutants, Harmful effects of Air Pollution, Control of Air Pollution. . Noise Pollution Harmful Effects of noise pollution, control of noise pollution, Global warming & Climate Change, Ozone depletion, Greenhouse effect
Text Books:
1. Palancharmy, Basic Civil Engineering, McGraw Hill publishers.
2. Satheesh Gopi, Basic Civil Engineering, Pearson Publishers.
3. Ketki Rangwala Dalal, Essentials of Civil Engineering, Charotar Publishing House.
4. BCP, Surveying volume 1
it describes the bony anatomy including the femoral head , acetabulum, labrum . also discusses the capsule , ligaments . muscle that act on the hip joint and the range of motion are outlined. factors affecting hip joint stability and weight transmission through the joint are summarized.
Temple of Asclepius in Thrace. Excavation resultsKrassimira Luka
The temple and the sanctuary around were dedicated to Asklepios Zmidrenus. This name has been known since 1875 when an inscription dedicated to him was discovered in Rome. The inscription is dated in 227 AD and was left by soldiers originating from the city of Philippopolis (modern Plovdiv).
BÀI TẬP DẠY THÊM TIẾNG ANH LỚP 7 CẢ NĂM FRIENDS PLUS SÁCH CHÂN TRỜI SÁNG TẠO ...
Balaram Lecture slides
1. Agilent 1100 LC MSD Model
In 1997 HP introduces its first benchtop
quadrupole LC/MS the 1100 Series LC/MSD
Journal of the American Society forMassSpectrometry 2001, 12 , 428–438
An Electrospray Ionization Mass Spectrometry Investigation of
1-Anilino-8-NaphthaleneSulfonate (ANS) Binding to Proteins
Learning Biological Mass Spectrometry
2. 1989 Physics W. PAUL and H. G. DEHMELT
…………for the development of the ion trap technique
1922 Chemistry F. W. ASTON
…………discovery, by means of the mass spectrograph, of
isotopes, in a large number of non-radioactive elements,
and for the enunciation of the whole-number rule.
1906 Physics J. J. THOMSON
…...........theoretical and experimental investigations on the
conduction of electricity by gases
2002 Chemistry K.TANAKA and J. B. FENN
…………development of soft desorption ionisation methods for
mass spectrometric analyses of biological
macromolecules
Mass Spectrometry
3. Prof. John Fenn
2002 NOBEL PRIZE IN CHEMISTRY
http://www.chem.ed.ac.uk/teaching/undergrad/chemistry4/lectures/moduleE/msd/PB/PBmsdlecture.pdf
Science 1989, 246,64-71
Fenn J B, ‘Electrospray wings for
molecular elephants’ (Nobel lecture),
Angew. Chem. Int. Ed., 42, 3871 (2003)
R.Sinatra etal., Science 2016,354,596
4. Serum
Red blood cells
Osmotic lysis releases
Hemoglobin molecules
Blood
Sample
Centrifuged
Distilled H2O
Human serum albumin
Human hemoglobin
Extracellular protein
Intracellular protein
Proteins can be chemically modified by reactive
molecules generated in cells under disease conditions
5. Mass (M) : 66438 Da
chain
15126Da
chain
15865 Da
Human Hemoglobin
m/z800 1000 12000
40
100
934.2
757.2
946.3
1009.3
1134.3
1164.4
(+14)
(+16)
(+13)
(+17)
(+15)
Human Serum Albumin
Electrospray Mass Spectra: Proteins
6. Molluscivorous (Prey --- Mollusc)
Piscivorous (Ingestion)
Marine cone snail venom may contain several hundred peptides that
target membrane receptor and channels. Conotoxins are upto 50
residues in length and contain multiple
disulfide bonds
Prof.K.S.Krishnan ( 1946-2014)
8. “CONOTOXINOMICS” (Olivera B. M., Toxicon 39, 7-14, 2001)
SINGLE
DISULFIDE
Conopressin Contryphan
Peptide Toxins Modifying Enzymes
Many Snails, Many Peptides and Many Enzymes
9. Target neuropathic pain
potent blocker of neuronal nAChRs ( α 9 α 10 )
Vc1.1 clinical trials discontinued after phase 2A. Efficacy concerns, lower affinity for human
receptors compared to mouse receptors
α-conotoxin Vc1.1
NMR solution sructure (PDB:2H8S)
Nicotinic acetylcholine receptors antagonists ( Alpha Conotoxins)
GCCSVPPCIANHPELCG
DCCSRPPCRWSHPELCS
ECCSHPACNVDHPEICR
GCCSVPPCIANHPELCV
Vc1.1 c.victoriae
PeIA c.pergrandis
LvIA c.lividus
AmIA c.amadis
AmIB c.amadis
AmIIA c.amadis
AmIIB c.amadis
Eline K. M. Lebbe, Steve Peigneur, Isuru Wijesekara and Jan Tytgat ,
Conotoxins Targeting Nicotinic Acetylcholine Receptors: An Overview,
Mar. Drugs 2014, 12, 2970-3004;
10. Sequencing peptides from natural mixtures
Complex mixtures Purified peptides
HPLC
Edman sequencingMass spectrometry
Difficulties with
post translational
modifications
Difficulties with
de novo
sequencing
Absence of adequate
numbers of fragment ions
to facilitate unambiguous
residue assignment
Liquid chromatography /
Mass spectrometry LC-MS
electrospray ionisation permits
ready coupling of HPLC and
Mass spectrometry
Conus venom contains a complex mixture of
heavily post translationally modified peptides
11. 0 10 20 30 40 50 60 Time [min]
0
1
2
3
4
7x10
Intens.
620.6
625.9
626.2
626.6
626.9
627.2
627.6
627.9
0.00
6
Intens.
620 621 622 623 624 625 626 627 628m/z
724.8
725.3
725.8
726.3
724.3
0.0
0.2
0.4
0.6
0.8
6x10
Intens.
724.0 724.5 725.0 725.5 726.0 726.5 727.0 m/z
Demonstration of High Sensitivity at High Resolution
Nano LC MS Profile of Crude venom of C. araneosus
5 mg Crude Venom
in 1000 ul
(M+3H)+3, M:1874.7Da (M+2H)+2
M:1446.6 Da
Diluted to 100000 times
Injection volume: 1ul
~ < 0.000000005 mg
12. REDUCTIVE ALKYLATION OF DISULFIDES
S
S
SH
SH
S
SpH 3
TCEP
pH 3
ΔM: 2*126.1= 252.2
N C C
CH2
S
O
H
H
M(RES)= 228
NEM
Alkylating agents M ΔM Mres
N-Ethylmaleimide 125.1 126.1 228
Iodoacetamide 184.96 58 160
2-Vinylpyridine 105.14 106.1 208
14. Mass: Mono:1368.681 / Average:1369.518 C63H96N14O20
+ + +- -- -
RNH2
RCOOH
RNH3
+
RCOO-
pKa
pKa
Distribution of multiple of charged states (M+nH)n+
In ESI-MS spectra determined by number of basic, protonatable sites
(memory of the solution state is retained)
In MALDI spectra Na+ / K+ adducts determined by number of RCOO-
18. X Y H V V S A N T X W S X V
b ions
y ions
274.3
2056.6
387.1
1943.6
550.1
1779.6
687.2
1642.6
786.3
1543.6
G P
885.7
942.5
1039.5
1339.5
1426.5
1497.4
1611.4
1712.6
1825.8
2011.8
2098.8
2211.8
1387.6
1290.5
H Y
1176.5
Partial Sequence Information Obtained through Chemical Derivatization
Unsolved Problems
1. N-terminal residues
2. Distinction between Ile (I), Leu (L) and Hyp (O) at three positions(X)
X Leucine (L) 113.1 Da Isoleucine (I) 113.1 Da Hydroxyproline (O) 113.2
NH
O
CH3
CH3 NH
O
CH3
CH3
N
O
OH
Isobaric amino acids
May be resolved through
high resolution mass measurements
FT-ICR MS, Orbitrap
??
19. X Y H V S A N T X W S X V
b ions
y ions
274.2
2056.6
387.1
1943.6
550.1
1779.6
687.2
1642.6
786.3
1543.6
R P
942.5
1039.5
1339.5
1426.5
1497.4
1611.4
1712.6
1825.8
2011.8
2098.8
2211.8
1387.6
1290.5
X = I/L/O
H Y
1176.5
Improved Sequence Information through MS3 Experiment
Unsolved Problems
1. N-terminal residues ( W or S-V- or V-S-) (186.9 Da)
2. Distinction between Ile (I), Leu (L) and Hyp (O) at three positions
186.9
S??
22. 2040.6
0
200
400
600
800
Intens.
2036 2040 2044 2048 2052 m/z m/z
2115.9
2116.9
2117.9
2118.9
0
1000
2000
3000
4000
5000
Intens.
2105 2110 2115 2120 2125 2130m
Presence of these ions negates the possibility of Hydroxyproline at the positions of X
N
O
OH
OH
N
O
OH
OH
N-C bond cleavage at Xxx- Pro/Hyp segment
c & z ions absent
26. Number of Conus peptide Expected from a single species: ~100
Number of Conus peptide Obtained from a single species: ~37
(~ 100 x 1/3)
Crude venom
HPLC
Mass spectrometry
Chemical Modification
Insensitivity off-line purifications
Imperfection of chemical reactions
H Teralu, BM Olivera Physiol. Rev. 2004, 84, 41
BM Ueberheide, D Fenyo, PF Alewood, BT Chait PNAS 2009, 106, 6910
28. conus araneosus
MALDI analysis of HPLC peaks establishes large number of peptide
Conus araneosus – Rameswaram, Tamil Nadu
De novo sequencing is difficult
mRNA
cDNA
NGS
Assembly
Conotoxin gene
>Conotoxin
MKLTCVVIAVLLLTACQLITADDSRGTQKHALRSTTKLSTSTRCKGKGAKCSRLMYDCCTGSCRSGKCG
Masses expected to be present in NGS
Mass spectral sequencing
29. Reading frame 4
Stop codon
Recognizing conotoxin gene related sequences
CC…..C…..C…C…C
signal pro region toxin
Proteolytic cleavage site
Post translation modification sites
Translation: 6 reading frames
30. Collecting shells and genes
C.loroissiC.amadis C.monileC.araneosus C.ebraeus C.lividus
Full
genes
Partial
genes
60
7
Total
toxin
sequences
67
49
20
69
61
20
81
36
20
56
6567
16
83
Post translational modifications create further diversity
72
7
C.Miles C.LitterattusC.Frigidus
93
15
78 49
9
58
53
14
67
33. C*- C* - D - W - D - W - C* - D - H - L - C* - T - C* - C* - G - G
EXPECTED FRAGMENTS FOR PEPTIDE 1813 (2569)
NEXT EXERCISE: ASSIGNING THE MASS SPECTRUM USING THE KNOWN SEQUENCE
44. HS CC SH
H
+ S CC S
H
ΔM = -2Da
Number of
Disulfide Bonded
Cysteines
Number of
Disulfide Isomers
4 3
6
8
15
105
n (n-1).(n-3).(n-5)…..(n-(n-1))
34
S S
SS
S S
SS
S S
SS
Disulfide Isomers: Same sequence different connectivity
.. ..
Oxidation
Reduction
46620662575398912000
45. G-V-C1-C2-G-V-S-F-C3-Y-O-C4
Ar1248 : Two Disulfide Bonds
1 6 12
..C1C2 …….C3..C4 ..C1C2…….C3..C4 ..C1C2……...C3...C4
..C1C2 + C3….C4
..C1C2
….C3..C4
..C1C2
….C3..C4
..C1
….C3
+
C2
..C4
..C1
..C4
+ C2
….C3
One Cleavage
Two Cleavages
3 Possible Disulfide Connectivities
46. Determination of Disulfide Connectivity in Polypeptides
Separation of Cystines
X1C1 X2..X3C2X4….X5C3 X6…X7 C4 X8
+
Peptide Bond Cleavage
Chemical Cleavage
Reagents:
Acid Hydrolysis (H2SO4, Oxalic)
CNBr (Met – Xxx Bond)
Enzymatic Cleavage
Reagents:
Trypsin (R/K – X bond)
Glu-C (E/D – X bond)
Asp-N (X – D bond)
Poor Selectivity
Limited Selectivity Range
X1C1 X2
X5C3 X6
X3C2 X4
X7C4 X8
47. Determination of Disulfide Connectivity in Polypeptides
Protocols of Partial Reduction & Alkylation
C1 .. C2…….C3 … C4
1st Reduction Step
C1 .. C2…….C3 … C4
SH SH
Chemical labeling (X)
C1 .. C2…….C3 … C4
X X
Next Reduction & labeling (Y)
X X
C1 .. C2…….C3 … C4
Y Y
Peptide Sequencing (Edman / Mass Spectrometry)
Chemical
Tris (2-carboxyethyl)phosphine
(TCEP)
Burns, JA; Butler, JC;
Moran, J; Whitesides, GM
J. Org. Chem. 1991, 56, 2648
Gray, WR
Protein Sci. 1993, 2, 1732
Limitations:
1. Difficulties in
achieving selective
Reduction
2. Thiol disulfide
interchange
48. H+
C S
S C
H
-H2S2(66 Da)
HS
Dehydroalanine
Residue Mass: 69Da
Cysteinpersulfide
Residue Mass: 135Da
Path A
H+
H
+
Cysteine
Residue Mass: 103Da
Cysteinthioaldehyde
Residue Mass: 101Da
Path B
Fragmentation at Disulfide Bridges Under CID Conditions
Disulfide Bridges
(Cystine)
-H2S(34 Da)
63. Utility of accurate mass measurements on proteins
Could the loss of MjTIM activity be a result of intramolecular
disulfide formation between two proximal thiol groups??
Cys-SH + HS- Cys Cys-S-S-Cys ∆M= -2 Da
Measured Mass using ESI-Q-TOF ( BRUKER, micrOTOF Q II)
MjTIM native = 23245.3 (Active)
MjTIM Heated for 3 hours at 348K at pH 6.7 = 23243.3 (Inactive)
MjTIM Heated for 3 hours at 348K at pH 8.8 =23243.3 (Inactive)
MjTIM Heated for 3 hours at 348K, pH 6.7
with reducing agent (DTT) =23245.2 (Active)
Enzymatically inactive sample appear to have a mass reduced by 2 Da
65. A Cys-Gly-Cys Motif in MjTIM
Inspection of crystal structure reveals that Cys81 and Cys83 are
appropriately positioned for oxidative S-S bond formation
Aº
73. S-S
H2N
H
N
O S
N
H
H
N
O
O H
HO2C
H2N
H2N
S
O
O
O
H
N
H
N
H
HO2C
H2N
O S
S
H2N
H2N
O
O
O H
+
+
S H
S
H2N
H
N
O
O
OH
NH3+
D-C-G-C-K
S S
DC
S S
m/z 523
m/z 523
m/z 394
m/z 282.1
+
S-S
D
C
G
K
C
K-C-G-C-D
S S
C-G-C-D
S S
m/z 377
m/z 505
m/z 505
S----S
D
C
G
K
CH H
HO2C
G-∆A-A-K-∆A m/z 395
-NH3
-CO
m/z 293
Gas phase cyclization
J Am Chem Soc.
2006, 128:10364
Harrison AG, Young AB,
Bleiholder C,
Suhai S, Paizs B.
74. 74
Hyperthermophilic archaeon
Inhihabits hydrothermal vents
A) (48- 940C)
B) Pressure 200 atm
Methanocaldococcus jannaschii Glutaminase
(MjGATase)
ATPPase
GATase is the smaller subunit of GMP synthetase
Hydrolyses glutamine and generates ammonia (ammonia donor)
Ammonia is tunnelled to ATPPase subunit to form GMP
Woods Hole Oceaonographic
institute
UC Berkeley EM lab.
GMP synthetase
JNCASR
76. 76
MjGATase
PhGATase
Sequence alignment of Pyrococcus horikoshii GATase with MjGATase shows
high degree of similarity
GLU 113
ILE 114
PHE115
GLU 111
ASP 110
2.8
3.27
SUCCINIMIDE
(ASP112 D*)
Mutational analysis to establish the sequence effects on
succinimide formation
I I D EDELFK
VDKENDLFK
PhGATase
MjGATase
PhGATase (1WL8)
crystal structure
with succinimide
Mass spec studies
MjGATse with
succinimide
109
ASP 112
H20
SUCCINIMIDE
ASN 109
N H3
SUCCINIMIDE
S/D
77. 77
Expected mass :21021Da
Observed mass :[A] 21003 Da
:[B] 21021 Da
657.0099
32+
678.1840
31+
700.7530
30+
724.8762
29+
750.7357
28+
778.4935
27+
808.4099
26+
840.7023
25+
875.6974
24+
913.7301
23+
955.2260
22+
1000.6621
21+
0.0
0.5
1.0
1.5
4
x10
Intens.
650 700 750 800 850 900 950 1000m/z
N109S
Expected mass :20993Da
Observed mass : 20993 Da
808.4099
26+
0.0
0.5
1.0
1.5
4
x10
Intens.
800 805 810 815 m/z
657.3341
32+
678.5049
31+
701.0899
30+
725.2292
29+
751.0914
28+ 808.7910
26+
841.1012
25+
876.1063
24+
914.1551
23+
955.6606
22+
1001.1227
21+
1051.1314
0
2
4
6
4x10
Intens.
650 700 750 800 850 900 950 1000 1050m/z
N109D
Substitution of N109 to S : Abolishment of succinimide
Replacement of N109 to D: like PhGATae forms succininimide
Expected mass :21021Da
Observed mas [A] : 21003 Da
[B]: 21021 Da
Mutational analysis on N109 confirms its conversion to succinimide
955.66
22+
956.49
22+
1
2
3
4
5
4x10
Intens.
956 m/z
[A]
[B]
78. Minus Succinimide
Increased floppiness
Structural collapsed
Plus Succinimide
Confers rigidity
Structural integrity
Increased molecular motion
High temperature
78
Succinimide : A molecular restrainer at high temperature
PhGATase (1WL8)
crystal structure
with succinimide