This PPT consists of types of asymmetric synthesis with examples. It consists of absolute asymmetric synthesis and partial asymmetric synthesis. The partial absolute synthesis consists of chiral pool, chiral catalyst, chiral reagent.
This document discusses various methods for asymmetric synthesis, which is a form of chemical synthesis that favors the formation of one stereoisomer over another. It begins by explaining enantioselective synthesis and its importance in pharmaceuticals. It then discusses using naturally occurring chiral compounds as starting materials, known as the "chiral pool". Examples of compounds in the chiral pool are discussed, such as amino acids and carbohydrates. Methods for using these compounds or derivatives in asymmetric synthesis are provided, such as through diastereoselective reactions. The document also discusses using chiral auxiliaries and catalysts to control stereoselectivity in reactions. Specific examples of chiral auxiliaries like oxazolidinones and catalytic reactions like asymmetric
Asymmetric synthesis FOR BSc, MSc, Bpharm, M,pharmShikha Popali
This document discusses different methods for asymmetric synthesis, which is the production of a single enantiomer from an achiral starting material. It describes chiral pool synthesis, which uses naturally occurring chiral compounds as starting materials. It also explains chiral auxiliaries, where an enantiopure auxiliary is attached and later removed, leaving the desired enantiomer. Chiral reagents and chiral catalysts are also discussed, where an enantiopure reagent or catalyst leads to an enantioselective reaction. Specific examples include the use of chiral boron hydrides and ligands like BINAP. Asymmetric hydrogenation is given as another key method. The document emphasizes the importance of these techniques for drug safety and mimicking nature.
The document discusses four generations of asymmetric synthesis techniques:
1) First generation uses a chiral substrate to control the formation of new chiral centers through diastereoselective reactions.
2) Second generation uses a chiral auxiliary covalently attached to the substrate to control asymmetric induction.
3) Third generation uses a chiral reagent or catalyst to induce asymmetry through intermolecular interactions.
4) Fourth generation involves catalytic versions of the first three generations and reactions where two new stereocenters are formed in one step, often using a chiral substrate and reagent.
This document summarizes several organic reactions used in heterocyclic chemistry. It describes the Debus–Radziszewski reaction for imidazole synthesis, the Knorr reaction for pyrrole synthesis, the Pinner reaction for pyrimidine synthesis, the Combes reaction for quinoline synthesis, the Bernthsen reaction for acridine synthesis, the Smiles rearrangement, and the Traube reaction for purine synthesis. For each reaction, it provides the starting materials, product, mechanism, and some applications. The document is intended to present an overview of important heterocyclic reactions for students of pharmaceutical chemistry.
Asymmetric synthesis is a chemical reaction that produces one stereoisomer in greater amounts than the other. It is achieved through the use of a chiral feature like a substrate, reagent, catalyst, or environment that favors the formation of one enantiomer over the other in the transition state. Some common approaches for asymmetric synthesis include using a chiral starting material from nature, attaching a chiral auxiliary, or employing a chiral reagent or catalyst. The separation and analysis of enantiomers can be challenging given their identical physical properties, requiring techniques like chiral chromatography or crystallization. Asymmetric synthesis has important applications in pharmaceuticals for producing drugs that are safer and more effective.
The document discusses several heterocyclic compounds including quinolines, isoquinolines, and indoles. It summarizes key reactions used to synthesize these compounds, including the Combes, Friedlander, Knorr, and Skraup reactions for quinoline synthesis. It also discusses the Bischler-Napieralski, Pictet-Spengler, and Pomeranz-Fritsch reactions for isoquinoline synthesis and the Fischer, Madelung, and Reissert reactions for indole synthesis, along with mechanisms and examples of each reaction. Reactivity and substitution patterns are also covered for quinolines, isoquinolines and indoles.
The document discusses nitration, which is the process of adding a nitro group to aromatic or aliphatic compounds. Nitration is carried out using a mixed acid reagent containing concentrated nitric acid and sulfuric acid. This generates nitronium ions that act as electrophiles in the reaction. The kinetics of nitration depend on factors like the substituents on the aromatic ring and the reaction medium. Aromatic compounds undergo nitration more easily than aliphatic compounds. The position and ratio of nitrated products is influenced by the electronic effects of substituents on the aromatic ring.
This document discusses various methods for asymmetric synthesis, which is a form of chemical synthesis that favors the formation of one stereoisomer over another. It begins by explaining enantioselective synthesis and its importance in pharmaceuticals. It then discusses using naturally occurring chiral compounds as starting materials, known as the "chiral pool". Examples of compounds in the chiral pool are discussed, such as amino acids and carbohydrates. Methods for using these compounds or derivatives in asymmetric synthesis are provided, such as through diastereoselective reactions. The document also discusses using chiral auxiliaries and catalysts to control stereoselectivity in reactions. Specific examples of chiral auxiliaries like oxazolidinones and catalytic reactions like asymmetric
Asymmetric synthesis FOR BSc, MSc, Bpharm, M,pharmShikha Popali
This document discusses different methods for asymmetric synthesis, which is the production of a single enantiomer from an achiral starting material. It describes chiral pool synthesis, which uses naturally occurring chiral compounds as starting materials. It also explains chiral auxiliaries, where an enantiopure auxiliary is attached and later removed, leaving the desired enantiomer. Chiral reagents and chiral catalysts are also discussed, where an enantiopure reagent or catalyst leads to an enantioselective reaction. Specific examples include the use of chiral boron hydrides and ligands like BINAP. Asymmetric hydrogenation is given as another key method. The document emphasizes the importance of these techniques for drug safety and mimicking nature.
The document discusses four generations of asymmetric synthesis techniques:
1) First generation uses a chiral substrate to control the formation of new chiral centers through diastereoselective reactions.
2) Second generation uses a chiral auxiliary covalently attached to the substrate to control asymmetric induction.
3) Third generation uses a chiral reagent or catalyst to induce asymmetry through intermolecular interactions.
4) Fourth generation involves catalytic versions of the first three generations and reactions where two new stereocenters are formed in one step, often using a chiral substrate and reagent.
This document summarizes several organic reactions used in heterocyclic chemistry. It describes the Debus–Radziszewski reaction for imidazole synthesis, the Knorr reaction for pyrrole synthesis, the Pinner reaction for pyrimidine synthesis, the Combes reaction for quinoline synthesis, the Bernthsen reaction for acridine synthesis, the Smiles rearrangement, and the Traube reaction for purine synthesis. For each reaction, it provides the starting materials, product, mechanism, and some applications. The document is intended to present an overview of important heterocyclic reactions for students of pharmaceutical chemistry.
Asymmetric synthesis is a chemical reaction that produces one stereoisomer in greater amounts than the other. It is achieved through the use of a chiral feature like a substrate, reagent, catalyst, or environment that favors the formation of one enantiomer over the other in the transition state. Some common approaches for asymmetric synthesis include using a chiral starting material from nature, attaching a chiral auxiliary, or employing a chiral reagent or catalyst. The separation and analysis of enantiomers can be challenging given their identical physical properties, requiring techniques like chiral chromatography or crystallization. Asymmetric synthesis has important applications in pharmaceuticals for producing drugs that are safer and more effective.
The document discusses several heterocyclic compounds including quinolines, isoquinolines, and indoles. It summarizes key reactions used to synthesize these compounds, including the Combes, Friedlander, Knorr, and Skraup reactions for quinoline synthesis. It also discusses the Bischler-Napieralski, Pictet-Spengler, and Pomeranz-Fritsch reactions for isoquinoline synthesis and the Fischer, Madelung, and Reissert reactions for indole synthesis, along with mechanisms and examples of each reaction. Reactivity and substitution patterns are also covered for quinolines, isoquinolines and indoles.
The document discusses nitration, which is the process of adding a nitro group to aromatic or aliphatic compounds. Nitration is carried out using a mixed acid reagent containing concentrated nitric acid and sulfuric acid. This generates nitronium ions that act as electrophiles in the reaction. The kinetics of nitration depend on factors like the substituents on the aromatic ring and the reaction medium. Aromatic compounds undergo nitration more easily than aliphatic compounds. The position and ratio of nitrated products is influenced by the electronic effects of substituents on the aromatic ring.
This document discusses strategies for synthesizing three, four, five, and six-membered heterocyclic rings. It outlines three strategies for each ring size, including the Gabriel ring closure and Hassner synthesis for aziridines, pyrolysis of cyclopropyl azides and photocycloaddition for azetines, the Paal-Knorr and Hantzsch syntheses for pyrroles, and the Hantzsch synthesis and reactions with maleic anhydride for pyridines and pyridazines. A variety of heterocyclic compounds are derived from carbocyclic precursors by replacing carbon atoms with heteroatoms like nitrogen, oxygen, or sulfur.
1) Heterolytic and homolytic bond fission can result in the formation of short-lived reaction intermediates called carbocations.
2) Carbocations are positively charged carbon ions that are electrophilic and undergo three reaction types: capture a nucleophile, lose a proton to form a pi bond, or rearrange.
3) Carbocation stability increases with increased substitution and the presence of electron donating groups, double bonds, or heteroatoms which delocalize the positive charge. Carbocations are key intermediates in SN1, E1, and rearrangement reactions.
This document discusses asymmetric synthesis, which produces unequal amounts of stereoisomers from achiral precursors. It can be enantioselective or diastereoselective. There are two types: partial asymmetric synthesis, which forms a new chiral center from an achiral precursor using a chiral substrate, auxiliary, reagent, or catalyst; and absolute asymmetric synthesis, which uses no chiral precursors but instead relies on physical chirality like circularly polarized light. Common approaches include using a chiral pool substrate, chiral auxiliary, chiral reagent, or chiral catalyst. The mechanisms and examples of various methods are explained in detail.
Enatiopure separation and stereo selective synthesis FOR PHARMACY STUDENTSShikha Popali
This document discusses methods for separating enantiomers and for performing stereo-selective synthesis. It describes 7 common methods for separating enantiomers from a racemic mixture: 1) mechanical separation, 2) preferential crystallization, 3) biochemical separation using microorganisms, 4) chromatographic separation, 5) kinetic resolution, 6) precipitation, and 7) forming diastereomers. It also defines enantioselective synthesis as a chemical reaction that produces unequal amounts of stereoisomeric products with new chiral elements. Examples of these separation methods and stereo-selective synthesis are provided.
Stereochemistry is the ‘chemistry of space’ , that is stereochemistry deals with the spatial arrangements of atoms and groups in a molecule.
Stereochemistry can trace its roots to the year 1842 when the French chemist Louis Pasteur made an observation that the salts of tartaric acid collected from a wine production vessel have the ability to rotate plane-polarized light, whereas the same salts from different sources did not have this ability.
Isomers are compounds that contain exactly the same number of atoms, i.e., they have exactly the same empirical formula, but differ from each other by the way in which the atoms are arranged.
Constitutional isomers, also known as structural isomers, are specific types of isomers that share the same molecular formula but have different bonding atomic organization and bonding patterns.
Stereoisomers are molecules having the same molecular formula and the atomic arrangement, but differ in their spatial arrangement.
Geometric isomers are two or more coordination compounds which contain the same number and types of atoms, and bonds (i.e., the connectivity between atoms is the same), but which have different spatial arrangements of the atoms.
There are 2 types of geometric isomers, ‘cis’ and ‘trans’.-cis isomers: when similar groups are present on the same side of the double bonds, then they are termed as cis.- trans isomers: when similar groups are present on the opposite sides of the double bonds then they are called trans isomers.
cis-diethylstilbestrol has only 7% of the estrogenic activity of trans-diethylstilbesterol.
Cisplatin have anticancer activity where ae trans platin is an inactive compound.
In chemistry, a molecule or ion is called chiral if it cannot be superposed on its mirror image by any combination of rotations, translations, and some conformational changes.
Chirality is the property of being non identical to ones mirror image.
Chiral center is defined as the atom bearing 4 different atoms or group of atoms.
Molecules that form nonsuperimposable mirror images, and thus exist as enantiomers, are said to be chiral molecules.
For a molecule to be chiral, it cannot contain a plane of symmetry.
The term enantioselectivity refers to the efficiency with which the reaction produces one enantiomer.
Enantiomers are stereoisomers that are non-superimposable mirror images.
Have identical properties.
Similar shapes
Diastereomers are stereoisomers that are non superimposable and are not mirror images.
Have distinct physical properties.
Have different molecular shapes.
Enantiomers consist of a pair of molecules that are mirror images of each other and are not superimposable.
When a molecule contains only one chiral centre , the two stereoisomers are known as enantiomers.
These may be referred to or labelled using the configurational descriptors as either:
R(rectus meaning right handed) or S(sinister meaning left handed),
D(dextrorotatory)or L (laevorotatory)
E-Entgegen or Z- Zusamen
This document discusses Traube purine synthesis and several purine derivatives including mercaptopurine, theophylline, and thioguanine. It provides information on:
- Traube first introduced purine synthesis in 1900 involving introduction of a one carbon fragment to bridge nitrogen atoms in pyrimidine rings.
- Mercaptopurine is used to treat cancers and autoimmune diseases but has side effects like bone marrow suppression and increased cancer risk.
- Theophylline is found in tea and used for respiratory issues like asthma as it relaxes bronchial muscles and stimulates the respiratory center.
- Thioguanine is used for certain cancers and inflammatory bowel disease.
The document discusses the Knorr pyrazole synthesis reaction which converts hydrazines or derivatives and 1,3-dicarbonyl compounds to pyrazoles using an acid catalyst. The mechanism involves acid-catalyzed imine formation on either carbonyl carbon, followed by attack of the other nitrogen on the other carbonyl group. This forms a diimine compound which deprotonates to generate the final pyrazole product. Several examples of pyrazoles synthesized using this reaction are mentioned, including antipyrine, celecoxib, and metamizole sodium which have various medical applications.
This document discusses heterocyclic compounds, specifically pyrazoles. It describes pyrazoles as a 5-membered heterocyclic ring containing two nitrogen atoms at the 1st and 2nd positions. Several common synthesis routes for pyrazoles are outlined, including the Paal-Knorr synthesis using 1,3-dicarbonyl compounds and hydrazines. The document also reviews reactions that pyrazoles undergo, such as electrophilic substitution, oxidation, and reduction. Finally, some medicinal uses of pyrazoles are provided, including their use as anti-pyretic, analgesic, and anti-inflammatory drugs.
The document discusses key concepts regarding enantiomers including:
1. Enantiomers are chiral molecules that are non-superimposable mirror images of one another that rotate plane-polarized light in opposite directions.
2. Diastereomers have more than one asymmetric carbon center and are physically different.
3. Differences in interactions between enantiomers and biological systems can lead to differences in pharmacological effects.
4. Stereoselectivity can occur during the absorption, distribution, metabolism, and excretion of chiral drugs due to interactions with transporters, proteins, and enzymes.
5. Case studies provide specific examples of how stereoselectivity influences the pharmacokinetics of drug enantiomers
stereochemistry and drug action ; basic introduction about stereochemistry and stereoisomers ; pharmacokinetic and pharmacodynamics concept of stereochemistry ; easson Stedman hypothesis ; stereo selectivity criteria .
This document discusses various aspects of stereochemistry. It begins by explaining Fischer's D and L notation system for assigning configurations based on a compound's relation to glyceraldehyde. It then discusses pseudo asymmetric centers in meso compounds and cis-trans isomerism that can occur due to restricted bond rotation around double bonds. Finally, it introduces the E-Z system for naming geometric isomers with three or more different groups, which is based on Cahn-Ingold-Prelog priority rules to determine whether higher priority groups are on the same or opposite sides of the double bond.
It is an intramolecular rearrangement reaction in which the 1,2-migration of silyl group from carbon to oxygen under basic conditions.It involves the formation of a pentacoordinate siliconintermediate.Discovered by Adrian Gibbs Brook in 1958.
Heterocyclic Organic Reaction - By Vishal DakhaleVishalDakhale
This document discusses three heterocyclic organic reactions: the Debus-Radziszewski imidazole synthesis, the Knorr pyrazole synthesis, and the Combes quinoline synthesis. The Debus-Radziszewski reaction synthesizes imidazoles from a dicarbonyl, aldehyde, and ammonia. The Knorr reaction synthesizes pyrazoles from hydrazines and 1,3-dicarbonyl compounds using an acid catalyst. The Combes reaction synthesizes quinolines by condensing unsubstituted anilines with β-diketones followed by an acid-catalyzed ring closure.
GC-AAS combines gas chromatography (GC) and atomic absorption spectroscopy (AAS). GC separates components and AAS performs elemental identification. GC-AAS is useful for determining specific organometallic compounds in environmental samples with low detection limits and high precision. It is widely used to analyze arsenic, antimony, mercury, lead and thallium. GC-AAS directly introduces separated gas components into an atomic absorption spectrometer for analysis and determination.
This document discusses isomerism and stereochemistry. It defines isomers as compounds with the same molecular formula but different structures or arrangements. Isomerism includes structural isomers like chain, positional, and functional isomers as well as stereoisomers. Stereoisomers have the same connectivity but different spatial arrangements and include enantiomers, which are non-superimposable mirror images, and diastereomers. Chiral molecules lack symmetry elements like planes and centers of symmetry and cannot be superimposed on their mirror images, while achiral molecules can.
This document discusses different methods of asymmetric synthesis, which is a type of chemical reaction that produces unequal amounts of stereoisomeric products. It describes three main approaches: using a chiral starting material from natural sources (chiral pool synthesis), introducing chirality with an auxiliary group that is later removed (chiral auxiliaries), and using a chiral catalyst or reagent (external asymmetric induction). Examples of each method are provided. The document also summarizes several ways to separate enantiomers, such as preferential crystallization, biochemical separation, and forming diastereomers.
The document discusses asymmetric synthesis, which is the synthesis of a single enantiomer of a chiral compound. It covers retrosynthetic analysis, using disconnections to plan multi-step syntheses. Functional group interconversion and two-group disconnections are recommended to avoid chemoselectivity problems. Chiral auxiliaries and resolving agents can be used to separate enantiomers. Chiral auxiliaries induce diastereoselectivity through steric effects to yield a single enantiomer of the product. An example reaction is given to synthesize (S)-1-(pyridine-3-yl)propan-1-ol using a chiral catalyst.
This document discusses strategies for synthesizing three, four, five, and six-membered heterocyclic rings. It outlines three strategies for each ring size, including the Gabriel ring closure and Hassner synthesis for aziridines, pyrolysis of cyclopropyl azides and photocycloaddition for azetines, the Paal-Knorr and Hantzsch syntheses for pyrroles, and the Hantzsch synthesis and reactions with maleic anhydride for pyridines and pyridazines. A variety of heterocyclic compounds are derived from carbocyclic precursors by replacing carbon atoms with heteroatoms like nitrogen, oxygen, or sulfur.
1) Heterolytic and homolytic bond fission can result in the formation of short-lived reaction intermediates called carbocations.
2) Carbocations are positively charged carbon ions that are electrophilic and undergo three reaction types: capture a nucleophile, lose a proton to form a pi bond, or rearrange.
3) Carbocation stability increases with increased substitution and the presence of electron donating groups, double bonds, or heteroatoms which delocalize the positive charge. Carbocations are key intermediates in SN1, E1, and rearrangement reactions.
This document discusses asymmetric synthesis, which produces unequal amounts of stereoisomers from achiral precursors. It can be enantioselective or diastereoselective. There are two types: partial asymmetric synthesis, which forms a new chiral center from an achiral precursor using a chiral substrate, auxiliary, reagent, or catalyst; and absolute asymmetric synthesis, which uses no chiral precursors but instead relies on physical chirality like circularly polarized light. Common approaches include using a chiral pool substrate, chiral auxiliary, chiral reagent, or chiral catalyst. The mechanisms and examples of various methods are explained in detail.
Enatiopure separation and stereo selective synthesis FOR PHARMACY STUDENTSShikha Popali
This document discusses methods for separating enantiomers and for performing stereo-selective synthesis. It describes 7 common methods for separating enantiomers from a racemic mixture: 1) mechanical separation, 2) preferential crystallization, 3) biochemical separation using microorganisms, 4) chromatographic separation, 5) kinetic resolution, 6) precipitation, and 7) forming diastereomers. It also defines enantioselective synthesis as a chemical reaction that produces unequal amounts of stereoisomeric products with new chiral elements. Examples of these separation methods and stereo-selective synthesis are provided.
Stereochemistry is the ‘chemistry of space’ , that is stereochemistry deals with the spatial arrangements of atoms and groups in a molecule.
Stereochemistry can trace its roots to the year 1842 when the French chemist Louis Pasteur made an observation that the salts of tartaric acid collected from a wine production vessel have the ability to rotate plane-polarized light, whereas the same salts from different sources did not have this ability.
Isomers are compounds that contain exactly the same number of atoms, i.e., they have exactly the same empirical formula, but differ from each other by the way in which the atoms are arranged.
Constitutional isomers, also known as structural isomers, are specific types of isomers that share the same molecular formula but have different bonding atomic organization and bonding patterns.
Stereoisomers are molecules having the same molecular formula and the atomic arrangement, but differ in their spatial arrangement.
Geometric isomers are two or more coordination compounds which contain the same number and types of atoms, and bonds (i.e., the connectivity between atoms is the same), but which have different spatial arrangements of the atoms.
There are 2 types of geometric isomers, ‘cis’ and ‘trans’.-cis isomers: when similar groups are present on the same side of the double bonds, then they are termed as cis.- trans isomers: when similar groups are present on the opposite sides of the double bonds then they are called trans isomers.
cis-diethylstilbestrol has only 7% of the estrogenic activity of trans-diethylstilbesterol.
Cisplatin have anticancer activity where ae trans platin is an inactive compound.
In chemistry, a molecule or ion is called chiral if it cannot be superposed on its mirror image by any combination of rotations, translations, and some conformational changes.
Chirality is the property of being non identical to ones mirror image.
Chiral center is defined as the atom bearing 4 different atoms or group of atoms.
Molecules that form nonsuperimposable mirror images, and thus exist as enantiomers, are said to be chiral molecules.
For a molecule to be chiral, it cannot contain a plane of symmetry.
The term enantioselectivity refers to the efficiency with which the reaction produces one enantiomer.
Enantiomers are stereoisomers that are non-superimposable mirror images.
Have identical properties.
Similar shapes
Diastereomers are stereoisomers that are non superimposable and are not mirror images.
Have distinct physical properties.
Have different molecular shapes.
Enantiomers consist of a pair of molecules that are mirror images of each other and are not superimposable.
When a molecule contains only one chiral centre , the two stereoisomers are known as enantiomers.
These may be referred to or labelled using the configurational descriptors as either:
R(rectus meaning right handed) or S(sinister meaning left handed),
D(dextrorotatory)or L (laevorotatory)
E-Entgegen or Z- Zusamen
This document discusses Traube purine synthesis and several purine derivatives including mercaptopurine, theophylline, and thioguanine. It provides information on:
- Traube first introduced purine synthesis in 1900 involving introduction of a one carbon fragment to bridge nitrogen atoms in pyrimidine rings.
- Mercaptopurine is used to treat cancers and autoimmune diseases but has side effects like bone marrow suppression and increased cancer risk.
- Theophylline is found in tea and used for respiratory issues like asthma as it relaxes bronchial muscles and stimulates the respiratory center.
- Thioguanine is used for certain cancers and inflammatory bowel disease.
The document discusses the Knorr pyrazole synthesis reaction which converts hydrazines or derivatives and 1,3-dicarbonyl compounds to pyrazoles using an acid catalyst. The mechanism involves acid-catalyzed imine formation on either carbonyl carbon, followed by attack of the other nitrogen on the other carbonyl group. This forms a diimine compound which deprotonates to generate the final pyrazole product. Several examples of pyrazoles synthesized using this reaction are mentioned, including antipyrine, celecoxib, and metamizole sodium which have various medical applications.
This document discusses heterocyclic compounds, specifically pyrazoles. It describes pyrazoles as a 5-membered heterocyclic ring containing two nitrogen atoms at the 1st and 2nd positions. Several common synthesis routes for pyrazoles are outlined, including the Paal-Knorr synthesis using 1,3-dicarbonyl compounds and hydrazines. The document also reviews reactions that pyrazoles undergo, such as electrophilic substitution, oxidation, and reduction. Finally, some medicinal uses of pyrazoles are provided, including their use as anti-pyretic, analgesic, and anti-inflammatory drugs.
The document discusses key concepts regarding enantiomers including:
1. Enantiomers are chiral molecules that are non-superimposable mirror images of one another that rotate plane-polarized light in opposite directions.
2. Diastereomers have more than one asymmetric carbon center and are physically different.
3. Differences in interactions between enantiomers and biological systems can lead to differences in pharmacological effects.
4. Stereoselectivity can occur during the absorption, distribution, metabolism, and excretion of chiral drugs due to interactions with transporters, proteins, and enzymes.
5. Case studies provide specific examples of how stereoselectivity influences the pharmacokinetics of drug enantiomers
stereochemistry and drug action ; basic introduction about stereochemistry and stereoisomers ; pharmacokinetic and pharmacodynamics concept of stereochemistry ; easson Stedman hypothesis ; stereo selectivity criteria .
This document discusses various aspects of stereochemistry. It begins by explaining Fischer's D and L notation system for assigning configurations based on a compound's relation to glyceraldehyde. It then discusses pseudo asymmetric centers in meso compounds and cis-trans isomerism that can occur due to restricted bond rotation around double bonds. Finally, it introduces the E-Z system for naming geometric isomers with three or more different groups, which is based on Cahn-Ingold-Prelog priority rules to determine whether higher priority groups are on the same or opposite sides of the double bond.
It is an intramolecular rearrangement reaction in which the 1,2-migration of silyl group from carbon to oxygen under basic conditions.It involves the formation of a pentacoordinate siliconintermediate.Discovered by Adrian Gibbs Brook in 1958.
Heterocyclic Organic Reaction - By Vishal DakhaleVishalDakhale
This document discusses three heterocyclic organic reactions: the Debus-Radziszewski imidazole synthesis, the Knorr pyrazole synthesis, and the Combes quinoline synthesis. The Debus-Radziszewski reaction synthesizes imidazoles from a dicarbonyl, aldehyde, and ammonia. The Knorr reaction synthesizes pyrazoles from hydrazines and 1,3-dicarbonyl compounds using an acid catalyst. The Combes reaction synthesizes quinolines by condensing unsubstituted anilines with β-diketones followed by an acid-catalyzed ring closure.
GC-AAS combines gas chromatography (GC) and atomic absorption spectroscopy (AAS). GC separates components and AAS performs elemental identification. GC-AAS is useful for determining specific organometallic compounds in environmental samples with low detection limits and high precision. It is widely used to analyze arsenic, antimony, mercury, lead and thallium. GC-AAS directly introduces separated gas components into an atomic absorption spectrometer for analysis and determination.
This document discusses isomerism and stereochemistry. It defines isomers as compounds with the same molecular formula but different structures or arrangements. Isomerism includes structural isomers like chain, positional, and functional isomers as well as stereoisomers. Stereoisomers have the same connectivity but different spatial arrangements and include enantiomers, which are non-superimposable mirror images, and diastereomers. Chiral molecules lack symmetry elements like planes and centers of symmetry and cannot be superimposed on their mirror images, while achiral molecules can.
This document discusses different methods of asymmetric synthesis, which is a type of chemical reaction that produces unequal amounts of stereoisomeric products. It describes three main approaches: using a chiral starting material from natural sources (chiral pool synthesis), introducing chirality with an auxiliary group that is later removed (chiral auxiliaries), and using a chiral catalyst or reagent (external asymmetric induction). Examples of each method are provided. The document also summarizes several ways to separate enantiomers, such as preferential crystallization, biochemical separation, and forming diastereomers.
The document discusses asymmetric synthesis, which is the synthesis of a single enantiomer of a chiral compound. It covers retrosynthetic analysis, using disconnections to plan multi-step syntheses. Functional group interconversion and two-group disconnections are recommended to avoid chemoselectivity problems. Chiral auxiliaries and resolving agents can be used to separate enantiomers. Chiral auxiliaries induce diastereoselectivity through steric effects to yield a single enantiomer of the product. An example reaction is given to synthesize (S)-1-(pyridine-3-yl)propan-1-ol using a chiral catalyst.
Combinatorial chemistry and high throughputscreeningSaikiranKulkarni
Combinatorial chemistry is a collection of techniques which allow for the synthesis of multiple compounds at the same time.
Combinatorial chemistry is one of the important new methodologies developed by researchers in the pharmaceutical industry to reduce the time and costs associated with producing effective and competitive new drugs, By accelerating the process of chemical synthesis, this method is having a profound effect on all branches of chemistry, but especially on drug discovery.
This document discusses several techniques for drug analysis including chromatography methods like high performance liquid chromatography (HPLC), gas chromatography (GC), and liquid chromatography-mass spectrometry (LC-MS). It also summarizes various immunoassay techniques such as radioimmunoassay, particle enhanced turbidimetric inhibition immunoassay, enzyme immunoassay, enzyme multiplied immunoassay technique, fluorescence polarization immunoassay, and chemiluminescence assays. Additional methods covered are affinity chrome-mediated immunoassay, and cloned enzyme donor immunoassay.
It is the presentation for Combinatorial Chemistry. this presentation should be helpful for B. Pharm students. It includes introduction, types, applications, advantages and disadvantages.
Combinatorial chemistry and high throughput screeningAnji Reddy
Combinatorial chemistry and high-throughput screening techniques allow for the rapid synthesis and testing of large libraries of compounds. Combinatorial chemistry uses solid and solution phase methods to efficiently produce thousands of compounds, while high-throughput screening employs automated instrumentation like microtiter plates to quickly assess large numbers of compounds through functional or non-functional assays. These approaches provide advantages for drug discovery by facilitating the identification of hit compounds for further optimization into drug leads.
An amino acid analyzer uses ion-exchange chromatography and post-column reaction with ninhydrin to detect and quantify amino acids in solutions. The system works by automatically injecting samples, separating amino acids using buffers of varying pH in a column, reacting the column eluent with ninhydrin in a coil to produce colored compounds, and using a photometer and recorder to identify and measure the amino acids based on their retention times and absorption peaks. The amino acid analyzer can analyze over 40 amino acids and is used to detect amino acids in tissues, fluids, foods and more.
Combinatorial chemistry is a technique used to rapidly produce large libraries of potential drug molecules. It allows scientists to create and evaluate thousands of similar compounds in parallel. The key advantages are that it is faster and more economical than traditional drug discovery methods. Some challenges include ensuring diversity in the compound libraries and identifying the active components within mixture samples. Solid phase synthesis and parallel/mixed synthesis are common techniques used in combinatorial chemistry approaches.
The document discusses bio-catalysis and the use of enzymes in organic synthesis. It notes that bio-catalysts are derived from renewable resources, are biodegradable, and allow reactions to proceed under mild conditions. Examples are given of green bio-catalytic processes developed by Pfizer and Codexis for manufacturing pharmaceuticals. The types of bio-catalyst enzymes are described along with their advantages over traditional chemical catalysts. Methods of immobilizing enzymes on supports are summarized, including entrapment, cross-linking, and attachment to porous or nano-structured materials.
This document discusses various methods for separating enantiomers, which are non-superimposable mirror images of chiral molecules. It describes how resolution of a racemic mixture into individual enantiomers can be achieved through forming diastereomeric salts or compounds with a resolving agent that have different physical properties and can thus be separated. Specific techniques covered include crystallization, use of chiral stationary phases in chromatography, enzymatic resolution, kinetic resolution, and capillary electrophoresis using cyclodextrins as selectors.
The document describes several different analytic techniques used in chemistry and biochemistry, including amino acid analysis, spectrophotometry, atomic absorption spectrometry, titrimetry, gravity separation, polarimetry, and fluorometry. Amino acid analysis uses ion exchange liquid chromatography to separate and quantify amino acids. Spectrophotometry measures light absorption to determine chemical concentrations. Atomic absorption spectrometry analyzes metals using flame or furnace atomic absorption. Titrimetry determines concentrations via acid-base or redox reactions with a standard solution. Gravity separation separates components by specific weight. Polarimetry measures sample rotation of polarized light. Fluorometry has greater sensitivity than spectrophotometry in detecting fluorescent compounds.
this slide contains all the basic about the topic ion exchange chromatography which contains all important information about topic in very easy language. it will be helpful for BSc, pharmacy and biomedical student.
This document discusses combinatorial chemistry techniques for rapidly producing large numbers of similar molecules for screening. It defines combinatorial chemistry as producing large numbers of analogs through the same reaction conditions. Solid phase synthesis on resin beads allows many reactions to occur in parallel. Methods like Houghton's "tea bag" approach and automated parallel synthesis in multi-well plates enable producing analog libraries. Mixed combinatorial synthesis combines reactants in mixtures that are then split and recombined to generate compound libraries without defining each structure. These techniques increase the efficiency and throughput of drug discovery.
Chiral HPLC uses an asymmetric chromatographic system to separate enantiomers. There are three main methods: using a chiral mobile phase, chiral liquid stationary phase, or chiral solid stationary phase. The chiral species forms diastereomeric complexes with the enantiomers, allowing separation. Indirect separation is also possible by derivatizing the enantiomers to form diastereomers, which can be separated on a non-chiral system. Common stationary phases include proteins, Pirkle compounds, cellulose/amylose derivatives, macrocyclic glycopeptides, and cyclodextrins. Applications include separating drug enantiomers and fullerenes.
This document provides information on immobilized enzyme systems. It discusses various methods of enzyme immobilization including entrapment, surface immobilization, and cross-linking. Entrapment involves localizing the enzyme within a polymer matrix or membrane, while surface immobilization attaches the enzyme to an insoluble carrier via adsorption, ionic binding, or covalent attachment. Cross-linking uses bifunctional reagents to crosslink enzyme molecules. The document also covers the kinetics, stability, and applications of immobilized enzymes, noting they have advantages like easy separation and reusability compared to soluble enzymes.
Combinatorial chemistry is a technique used to rapidly produce large libraries of compounds for screening. It involves combining building blocks such as amino acids or organic fragments in all possible combinations in a parallel or mixed format. This allows for the efficient synthesis and screening of thousands of compounds. Key applications of combinatorial chemistry include drug discovery and optimization by increasing the probability of identifying novel compounds with therapeutic potential. Advantages include speed, lower cost, and the ability to screen large numbers of compounds simultaneously.
The document discusses immobilization of enzymes. There are several reasons for immobilizing enzymes, including easy separation of the enzyme from reaction products and reuse of the enzyme. Common immobilization methods include covalent binding of the enzyme to a support, entrapment within a polymer matrix, and cross-linking. Supports can be inorganic materials like silica or organic polymers. Immobilization can impact properties of enzymes like activity, pH optimum, and stability. Reversible immobilization allows regeneration of supports and is important for labile enzymes.
Travis Hills' Endeavors in Minnesota: Fostering Environmental and Economic Pr...Travis Hills MN
Travis Hills of Minnesota developed a method to convert waste into high-value dry fertilizer, significantly enriching soil quality. By providing farmers with a valuable resource derived from waste, Travis Hills helps enhance farm profitability while promoting environmental stewardship. Travis Hills' sustainable practices lead to cost savings and increased revenue for farmers by improving resource efficiency and reducing waste.
The debris of the ‘last major merger’ is dynamically youngSérgio Sacani
The Milky Way’s (MW) inner stellar halo contains an [Fe/H]-rich component with highly eccentric orbits, often referred to as the
‘last major merger.’ Hypotheses for the origin of this component include Gaia-Sausage/Enceladus (GSE), where the progenitor
collided with the MW proto-disc 8–11 Gyr ago, and the Virgo Radial Merger (VRM), where the progenitor collided with the
MW disc within the last 3 Gyr. These two scenarios make different predictions about observable structure in local phase space,
because the morphology of debris depends on how long it has had to phase mix. The recently identified phase-space folds in Gaia
DR3 have positive caustic velocities, making them fundamentally different than the phase-mixed chevrons found in simulations
at late times. Roughly 20 per cent of the stars in the prograde local stellar halo are associated with the observed caustics. Based
on a simple phase-mixing model, the observed number of caustics are consistent with a merger that occurred 1–2 Gyr ago.
We also compare the observed phase-space distribution to FIRE-2 Latte simulations of GSE-like mergers, using a quantitative
measurement of phase mixing (2D causticality). The observed local phase-space distribution best matches the simulated data
1–2 Gyr after collision, and certainly not later than 3 Gyr. This is further evidence that the progenitor of the ‘last major merger’
did not collide with the MW proto-disc at early times, as is thought for the GSE, but instead collided with the MW disc within
the last few Gyr, consistent with the body of work surrounding the VRM.
Describing and Interpreting an Immersive Learning Case with the Immersion Cub...Leonel Morgado
Current descriptions of immersive learning cases are often difficult or impossible to compare. This is due to a myriad of different options on what details to include, which aspects are relevant, and on the descriptive approaches employed. Also, these aspects often combine very specific details with more general guidelines or indicate intents and rationales without clarifying their implementation. In this paper we provide a method to describe immersive learning cases that is structured to enable comparisons, yet flexible enough to allow researchers and practitioners to decide which aspects to include. This method leverages a taxonomy that classifies educational aspects at three levels (uses, practices, and strategies) and then utilizes two frameworks, the Immersive Learning Brain and the Immersion Cube, to enable a structured description and interpretation of immersive learning cases. The method is then demonstrated on a published immersive learning case on training for wind turbine maintenance using virtual reality. Applying the method results in a structured artifact, the Immersive Learning Case Sheet, that tags the case with its proximal uses, practices, and strategies, and refines the free text case description to ensure that matching details are included. This contribution is thus a case description method in support of future comparative research of immersive learning cases. We then discuss how the resulting description and interpretation can be leveraged to change immersion learning cases, by enriching them (considering low-effort changes or additions) or innovating (exploring more challenging avenues of transformation). The method holds significant promise to support better-grounded research in immersive learning.
The ability to recreate computational results with minimal effort and actionable metrics provides a solid foundation for scientific research and software development. When people can replicate an analysis at the touch of a button using open-source software, open data, and methods to assess and compare proposals, it significantly eases verification of results, engagement with a diverse range of contributors, and progress. However, we have yet to fully achieve this; there are still many sociotechnical frictions.
Inspired by David Donoho's vision, this talk aims to revisit the three crucial pillars of frictionless reproducibility (data sharing, code sharing, and competitive challenges) with the perspective of deep software variability.
Our observation is that multiple layers — hardware, operating systems, third-party libraries, software versions, input data, compile-time options, and parameters — are subject to variability that exacerbates frictions but is also essential for achieving robust, generalizable results and fostering innovation. I will first review the literature, providing evidence of how the complex variability interactions across these layers affect qualitative and quantitative software properties, thereby complicating the reproduction and replication of scientific studies in various fields.
I will then present some software engineering and AI techniques that can support the strategic exploration of variability spaces. These include the use of abstractions and models (e.g., feature models), sampling strategies (e.g., uniform, random), cost-effective measurements (e.g., incremental build of software configurations), and dimensionality reduction methods (e.g., transfer learning, feature selection, software debloating).
I will finally argue that deep variability is both the problem and solution of frictionless reproducibility, calling the software science community to develop new methods and tools to manage variability and foster reproducibility in software systems.
Exposé invité Journées Nationales du GDR GPL 2024
Current Ms word generated power point presentation covers major details about the micronuclei test. It's significance and assays to conduct it. It is used to detect the micronuclei formation inside the cells of nearly every multicellular organism. It's formation takes place during chromosomal sepration at metaphase.
Phenomics assisted breeding in crop improvementIshaGoswami9
As the population is increasing and will reach about 9 billion upto 2050. Also due to climate change, it is difficult to meet the food requirement of such a large population. Facing the challenges presented by resource shortages, climate
change, and increasing global population, crop yield and quality need to be improved in a sustainable way over the coming decades. Genetic improvement by breeding is the best way to increase crop productivity. With the rapid progression of functional
genomics, an increasing number of crop genomes have been sequenced and dozens of genes influencing key agronomic traits have been identified. However, current genome sequence information has not been adequately exploited for understanding
the complex characteristics of multiple gene, owing to a lack of crop phenotypic data. Efficient, automatic, and accurate technologies and platforms that can capture phenotypic data that can
be linked to genomics information for crop improvement at all growth stages have become as important as genotyping. Thus,
high-throughput phenotyping has become the major bottleneck restricting crop breeding. Plant phenomics has been defined as the high-throughput, accurate acquisition and analysis of multi-dimensional phenotypes
during crop growing stages at the organism level, including the cell, tissue, organ, individual plant, plot, and field levels. With the rapid development of novel sensors, imaging technology,
and analysis methods, numerous infrastructure platforms have been developed for phenotyping.
hematic appreciation test is a psychological assessment tool used to measure an individual's appreciation and understanding of specific themes or topics. This test helps to evaluate an individual's ability to connect different ideas and concepts within a given theme, as well as their overall comprehension and interpretation skills. The results of the test can provide valuable insights into an individual's cognitive abilities, creativity, and critical thinking skills
The use of Nauplii and metanauplii artemia in aquaculture (brine shrimp).pptxMAGOTI ERNEST
Although Artemia has been known to man for centuries, its use as a food for the culture of larval organisms apparently began only in the 1930s, when several investigators found that it made an excellent food for newly hatched fish larvae (Litvinenko et al., 2023). As aquaculture developed in the 1960s and ‘70s, the use of Artemia also became more widespread, due both to its convenience and to its nutritional value for larval organisms (Arenas-Pardo et al., 2024). The fact that Artemia dormant cysts can be stored for long periods in cans, and then used as an off-the-shelf food requiring only 24 h of incubation makes them the most convenient, least labor-intensive, live food available for aquaculture (Sorgeloos & Roubach, 2021). The nutritional value of Artemia, especially for marine organisms, is not constant, but varies both geographically and temporally. During the last decade, however, both the causes of Artemia nutritional variability and methods to improve poorquality Artemia have been identified (Loufi et al., 2024).
Brine shrimp (Artemia spp.) are used in marine aquaculture worldwide. Annually, more than 2,000 metric tons of dry cysts are used for cultivation of fish, crustacean, and shellfish larva. Brine shrimp are important to aquaculture because newly hatched brine shrimp nauplii (larvae) provide a food source for many fish fry (Mozanzadeh et al., 2021). Culture and harvesting of brine shrimp eggs represents another aspect of the aquaculture industry. Nauplii and metanauplii of Artemia, commonly known as brine shrimp, play a crucial role in aquaculture due to their nutritional value and suitability as live feed for many aquatic species, particularly in larval stages (Sorgeloos & Roubach, 2021).
When I was asked to give a companion lecture in support of ‘The Philosophy of Science’ (https://shorturl.at/4pUXz) I decided not to walk through the detail of the many methodologies in order of use. Instead, I chose to employ a long standing, and ongoing, scientific development as an exemplar. And so, I chose the ever evolving story of Thermodynamics as a scientific investigation at its best.
Conducted over a period of >200 years, Thermodynamics R&D, and application, benefitted from the highest levels of professionalism, collaboration, and technical thoroughness. New layers of application, methodology, and practice were made possible by the progressive advance of technology. In turn, this has seen measurement and modelling accuracy continually improved at a micro and macro level.
Perhaps most importantly, Thermodynamics rapidly became a primary tool in the advance of applied science/engineering/technology, spanning micro-tech, to aerospace and cosmology. I can think of no better a story to illustrate the breadth of scientific methodologies and applications at their best.
3. INTRODUCTION
• Asymmetric synthesis is a reaction in which an achiral unit in a substrate molecule is converted
into a chiral unit in such a manner that unequal amounts of stereoisomers (enantiomers or
diastereomers) are produced.
• When a compound containing an asymmetric carbon (CHIRAL) is synthesized by conventional
laboratory methods from an achiral compound the product is a racemic mixture.
• If such a synthesis carried out under chiral influence, only one of optically active isomer will
form preferentially over the other.
4. • Asymmetric synthesis refers to the selective synthesis of one of the isomer of the chiral product.
• The enantiomers can be separated by the methods includes
-Chiral chromatography
-Enzymes
-Asymmetric synthesis.
• The asymmetric synthesis is also called as enantioselective synthesis.
A
B + BI
B
5. STEREOSPECIFIC REACTIONS STEREOSELECTIVE REACTIONS
A stereospecific reaction is a rection in
which the stereochemistry of the reactant
completely determines the stereochemistry
of the product without any other option.
A stereoselective reaction is a rection in
which there is a choice of pathway, but the
product stereoisomer is formed due to its
reaction pathway being more favorable than
the others available.
Gives a specific product from a certain
reactant.
Can result in multiple products.
Final product depends on the
stereochemistry of the reactant
Selectivity of the reaction pathway depends
on differences in steric effects an electronic
effects
SN2 reaction is an example for the
stereospecific reaction.
Dehydrohalogenation of 2-iodo butane
which yields 60% trans and 20% cis
6. MECHANISM
• The aim is to make enantiomers into diastereomers . To make this possible ,we need to incorporate
reagents or catalysts having chirality.
• The reaction will now proceed differently for different enantiomers because of the difference in
energy of transition state.
• In the absence of chiral influence, reaction producing enantiomers in equal amounts via transition
states of identical energies (enantiomeric transition state) . These reactions therefore takes place at
identical rates to give equal amounts of enantiomers
• If we are using chiral components , then we could make the possible enantiomeric transition state,
diastereomeric transition state with different activation energy which results in unequal amounts of
isomers
7.
8. GENERATIONS
• There are total four generations of asymmetric synthesis, those are
1st Generation – Substrate controlled asymmetric synthesis
Diastereoselective reactions where the formation of chiral centre is controlled by another chiral
centre already present in the substrate.
2nd Generation – Auxiliary controlled asymmetric synthesis
In this method a chiral auxiliary is covalently attached to the substrate and, through that controls the
asymmetric synthesis
3rd Generation – Reagent controlled asymmetric synthesis
The formation of a new chiral centre is induced by a chiral reagent, intramolecularly.
4th Generation – Catalyst controlled asymmetric synthesis
One general procedure involves a reaction of a chiral substrate with a chiral reagent, and is
especially useful in reactions where two new stereogenic units are formed stereo selectively in one
9. 1st Generation
Substrate* Product*
2nd Generation
Substrate + Auxiliary S-A P-A* Product*
3rd Generation
Substrate Product*
4th Generation
Substrate* Product*
Reagen
t
Reagen
t
Reagent
*
Catalyst
*
Auxiliary*
10. APPROACHES
Asymmetric synthesis are of 2 types
1.Partial asymmetric synthesis
2.Absolute asymmetric synthesis
Partial Asymmetric Synthesis-
Synthesis of new chiral center from an achiral center by using optically active reagents.
1.Use of chiral substrate-
• It uses natures ready-made chiral centers as starting materials
• It is more economical way of making compounds in enantiopure form.
• Eg. – Conversion L-tyrosine into L-DOPA.
• In this conversion starting material L-tyrosine is a naturally occurring chiral molecule.
• This conversion doesn’t affect the existing stereocenter.
11. • This method is also known as “ CHIRAL POOL” strategy.
• Pure natural products, usually amino acids or sugars, from which pieces containing the required
chiral centres can be taken and incorporated into product.
• It is an internal asymmetric induction – refers to the control of stereoselectivity exerted by an
existing chiral centre on the formation of new chiral centre.
• Chiral pool is the collection of cheap , readily available natural products .
• Eg:(+)nicotine, (+)tartaric acid, D-glyceraldehyde etc .
12. II Use of chiral auxiliary
• In this approach a prochiral substrate attach with a chiral auxiliary to give a chiral intermediate.
• During which auxiliary directs the preferred stereochemistry.
• Finally we can remove the auxiliary from product to use it again.
• It is an relayed asymmetric induction – refers to the control of stereoselectivity exerted by
chiral auxiliary on the formation of new chiral center
Eg- Asymmetric alkylation of cyclohexanone using SAMP
13. III Use of chiral reagents
• In this method an inactive substrate converted selectively into one of the enantiomer
(enantiospecific).
• In this type of synthesis chiral reagent turns achiral by transforming an achiral substrate to chiral.
• Thus the reagent is “self- immolative”
14. IV Use of chiral catalyst
• In this the chiral catalyst directs the formation of a chiral compound such that formation of one
stereoisomer is favored.
• Effective optically pure catalysts are much more promising , because reagents are required in
stoichiometric amounts ,while catalysts are required only in very small amounts.
• Eg: Catalytic asymmetric reduction of ketones
Catalytic asymmetric hydrogenation of alkenes
Asymmetric epoxidation.
Ru-catalysed asymmetric hydrogenation of unsaturated carboxylic acids
15. Ru-catalysed asymmetric hydrogenation of allylic alcohols
The industrial application for the catalytic asymmetric synthesis is the production of the
painkiller
(S)-naproxen
16. METHODS ADVANTAGES DISADVANTAGES
Chiral Pool 100% ee is guaranteed Often only 1 enantiomer available
Chiral Auxiliary
Often excellent ee & can
recrystallize to purify to high ee
Extra steps to introduce and
remove auxiliary
Chiral Reagent
Often excellent ee & can
recrystallize to purify to high ee
Only few reagents are successful
and often for few substrates
Chiral Catalyst
Economical, only small amounts
are recyclable material used
Only few reactions are really
successful
17. Absolute Asymmetric Synthesis
• It is the synthesis of optically active products from achiral substrate without the use of optically
active reagents.
• In this type of synthesis a physical presence of chirality is necessary.
• Eg: Addition of bromine to 2,4,6-trinitrostilbene give a dextrorotatory product.
• Here we are using circularly polarized light for the induction of chirality.
• The role of circularly polarized light is reminiscent of an optically active compound in
conventional resolution.
18. REFERENCES
1. Stereochemistry CONFORMATION AND MECHANISM – P S Kalsi
2. BASIC ORGANIC CHEMISTRY : Ernest L Eliel
3. Clayden, Jonathan, Nick Greeves and Stuart Warren. Organic Chemistry, 2nd Edition. Oxford.
2012.