5.12 Chirality in Nature and Chiral Environments
3 min read•may 7, 2024
is a game-changer in organic chemistry, affecting how molecules interact with our bodies. It's like having two gloves - they look the same, but only one fits your right hand perfectly. This concept is crucial for understanding drug effects and biological processes.
Chiral molecules are picky about who they dance with in our bodies. Like a key fitting a lock, only the right-shaped molecule can bind to a specific receptor. This selectivity is why some drugs work wonders while their mirror images might do nothing or even cause harm.
Chirality and Biological Activity
Chirality's impact on biological properties
Top images from around the web for Chirality's impact on biological properties
Frontiers | Chronic Fluoxetine Impairs the Effects of 5-HT1A and 5-HT2C Receptors Activation in ... View original
Is this image relevant?
Fluoxetine - Wikipedia View original
Is this image relevant?
Enhancement of Local Retionic Acid Signaling: A Pivotal Mechanism in Fluoxetine's Pleiotropic ... View original
Is this image relevant?
Frontiers | Chronic Fluoxetine Impairs the Effects of 5-HT1A and 5-HT2C Receptors Activation in ... View original
Is this image relevant?
Fluoxetine - Wikipedia View original
Is this image relevant?
1 of 3
Top images from around the web for Chirality's impact on biological properties
Frontiers | Chronic Fluoxetine Impairs the Effects of 5-HT1A and 5-HT2C Receptors Activation in ... View original
Is this image relevant?
Fluoxetine - Wikipedia View original
Is this image relevant?
Enhancement of Local Retionic Acid Signaling: A Pivotal Mechanism in Fluoxetine's Pleiotropic ... View original
Is this image relevant?
Frontiers | Chronic Fluoxetine Impairs the Effects of 5-HT1A and 5-HT2C Receptors Activation in ... View original
Is this image relevant?
Fluoxetine - Wikipedia View original
Is this image relevant?
1 of 3
- Chirality plays a crucial role in determining the biological properties of molecules
- can have different pharmacological effects despite having the same chemical formula (, )
- One enantiomer may be biologically active while the other is inactive or even harmful
- Fluoxetine, the active ingredient in Prozac, is a chiral molecule
- The is responsible for the antidepressant activity
- The has no significant antidepressant effect
- can have different pharmacological effects despite having the same chemical formula (, )
Chiral molecules and receptor interactions
- Chiral molecules interact with biological receptors through complementary shapes
- Receptors have specific three-dimensional structures that allow them to bind selectively to certain molecules (, )
- The shape of the receptor's binding site is complementary to the shape of the ligand (, )
- The "lock and key" model is an analogy for receptor-ligand interactions
- The receptor is the "lock" with a specific shape
- The ligand is the "key" that fits into the lock
- Only the correct enantiomer (the right "key") can fit properly into the receptor's binding site (, )
- Enantiomers have different three-dimensional shapes
- This difference in shape allows receptors to distinguish between enantiomers
- One enantiomer may bind strongly to the receptor, while the other may not bind at all or bind weakly (, )
- is a property of chiral molecules that can be used to distinguish between enantiomers
Chiral Environments and Selective Reactions
Prochiral substrates in chiral environments
- have two identical functional groups that can be distinguished in a chiral environment (, )
- These substrates are not chiral but can give rise to chiral products when reacted selectively
- Chiral environments can induce selective reactions on prochiral substrates
- are naturally occurring that can promote selective reactions (, )
- The chirality of the enzyme's active site influences the stereochemical outcome of the reaction
- The is an example of a selective reaction in a chiral environment
- Ethanol is a prochiral substrate with two identical hydrogen atoms on the -carbon
- In the presence of the enzyme alcohol dehydrogenase (ADH) and the cofactor (NAD+), one of the hydrogen atoms is selectively removed
- ADH's active site is chiral and can distinguish between the two hydrogen atoms
- The enzyme selectively abstracts the , resulting in the formation of with a specific
- The selectivity of this reaction is determined by the chirality of the enzyme's active site
Stereochemistry and Chiral Centers
- Stereochemistry is the study of the three-dimensional arrangement of atoms in molecules
- are atoms, typically carbon, bonded to four different groups
- are compounds with the same molecular formula but different spatial arrangements of atoms
- involves the creation of chiral molecules from achiral starting materials in chiral environments
Key Terms to Review (34)
(R)-enantiomer: The (R)-enantiomer is one of the two mirror-image forms of a chiral molecule. Chirality refers to the property of a molecule that has a non-superimposable mirror image, and the (R)-enantiomer is the specific orientation of the molecule that is designated with the 'R' configuration.
(S)-enantiomer: The (S)-enantiomer is one of the two possible stereoisomeric forms of a chiral molecule, where the 'S' refers to the spatial arrangement of the substituents around the chiral center. The (S)-enantiomer is a non-superimposable mirror image of the (R)-enantiomer, and the two forms often have different biological and chemical properties.
Acetaldehyde: Acetaldehyde is a colorless, flammable organic compound with the chemical formula CH3CHO. It is the simplest aliphatic aldehyde and is an important intermediate in various chemical processes and metabolic pathways.
Alcohol Dehydrogenase: Alcohol dehydrogenase (ADH) is an enzyme that catalyzes the oxidation of alcohols to aldehydes or ketones. It plays a crucial role in the metabolism of ethanol and other alcohols in the body, as well as in the regulation of chiral environments and the catalysis of enzymatic reactions.
Alkenes: Alkenes are a class of unsaturated organic compounds characterized by the presence of a carbon-carbon double bond. They are an important functional group in organic chemistry, with a wide range of applications and reactivity. Alkenes are closely related to the topics of chirality, isomerism, electrophilic addition reactions, halogenation, hydration, the E2 reaction, infrared spectroscopy, 13C NMR spectroscopy, alcohol preparation, and the Wittig reaction.
Anti stereochemistry: Anti stereochemistry describes the spatial arrangement in a chemical reaction where two substituents are positioned on opposite sides of a double bond or ring structure after the reaction. It is particularly relevant in the halogenation of alkenes, resulting in products where the added atoms are located across from each other.
Asymmetric Synthesis: Asymmetric synthesis is a chemical reaction that produces a chiral molecule in a stereoselective manner, resulting in the formation of one enantiomer or diastereomer in excess over the other. This concept is crucial in understanding various topics in organic chemistry, including Pasteur's discovery of enantiomers, chirality at nitrogen, phosphorus, and sulfur, prochirality, chirality in nature and chiral environments, and the synthesis of amino acids.
Chiral Catalysts: Chiral catalysts are enantioselective catalysts that can preferentially promote the formation of one enantiomer of a product over the other in a chemical reaction. These catalysts possess a chiral environment that allows them to interact differently with the reactants, leading to the selective formation of a desired stereoisomer.
Chiral Centers: Chiral centers are atoms within a molecule that have four different substituents attached, resulting in a non-superimposable mirror image. This asymmetry gives rise to the concept of chirality, which is essential in understanding optical activity, meso compounds, and the stereochemistry of various organic reactions and biomolecules.
Chirality: Chirality is a fundamental concept in organic chemistry that describes the three-dimensional arrangement of atoms in a molecule. It refers to the property of a molecule that is non-superimposable on its mirror image, resulting in the existence of two distinct forms known as enantiomers. Chirality is a crucial factor in understanding the behavior and properties of various organic compounds, including their interactions with living systems.
Chirality centers: A chirality center in organic chemistry is an atom, typically carbon, that has four different groups attached to it, leading to non-superimposable mirror image forms of the molecule. These centers are crucial for determining the 3D spatial orientation of molecules, affecting their chemical behavior and interactions.
Cytochrome P450: Cytochrome P450 is a superfamily of enzymes that play a crucial role in the metabolism and biosynthesis of various endogenous and exogenous compounds, including steroids and other lipids. These enzymes are found in most living organisms and are particularly important in the context of chirality and the biosynthesis of steroids.
D-glucose: D-glucose is a monosaccharide, the most abundant sugar found in nature. It is an aldose, meaning it has an aldehyde group at one end, and is the stereoisomer with the D-configuration, indicating the position of the hydroxyl group on the chiral carbon farthest from the aldehyde group.
Enantiomers: Enantiomers are a pair of stereoisomers that are non-superimposable mirror images of each other. They have the same molecular formula and connectivity, but differ in the spatial arrangement of their atoms, resulting in a unique handedness or chirality.
Enzymes: Enzymes are biological catalysts that speed up chemical reactions in living organisms without being consumed in the process. They play a crucial role in facilitating various biochemical reactions necessary for life, including those involved in metabolism and DNA replication.
Enzymes: Enzymes are biological catalysts that accelerate chemical reactions in living organisms. They are essential for a wide range of processes, from digestion to energy production, and play a crucial role in maintaining the delicate balance of biochemical reactions that sustain life.
Ethanol-NAD+ Reaction: The ethanol-NAD+ reaction is a crucial metabolic process in which ethanol is oxidized to acetaldehyde, with the concomitant reduction of the coenzyme NAD+ to NADH. This reaction is a key step in the metabolism of ethanol and has important implications in the context of chirality and chiral environments.
Fluoxetine: Fluoxetine is a selective serotonin reuptake inhibitor (SSRI) medication commonly used to treat depression, anxiety, and other mental health conditions. It works by increasing the availability of the neurotransmitter serotonin in the brain, which can help regulate mood and other physiological processes.
Hormones: Hormones are chemical messengers produced by the endocrine system that regulate various physiological processes and bodily functions. They play a crucial role in maintaining homeostasis and coordinating the body's response to internal and external stimuli, including those related to chirality in nature and chiral environments.
Ibuprofen: Ibuprofen is a non-steroidal anti-inflammatory drug (NSAID) commonly used to relieve pain, reduce inflammation, and lower fever. It is a chiral compound with two enantiomeric forms, which is relevant in the context of chirality in nature and chiral environments.
Ketones: Ketones are organic compounds characterized by a carbonyl group (C=O) bonded to two other carbon atoms within the molecule. They are formed by the oxidation of secondary alcohols.
Ketones: Ketones are a class of organic compounds containing a carbonyl group (C=O) bonded to two alkyl or aryl groups. They are characterized by the presence of a carbonyl carbon flanked by two carbon atoms. Ketones are important in various organic chemistry topics, including chirality, oxidation reactions, mass spectrometry, infrared spectroscopy, and NMR spectroscopy.
L-amino acids: L-amino acids are a class of amino acids that have the same absolute configuration as the naturally occurring amino acids found in proteins. They are the predominant form of amino acids utilized by living organisms in biochemical processes.
Morphine: Morphine is a naturally occurring opioid analgesic derived from the opium poppy plant. It is a powerful pain-relieving drug that has been widely used in medical and recreational contexts, with significant implications in the fields of chirality and polycyclic aromatic compounds.
Neurotransmitters: Neurotransmitters are chemical messengers that transmit signals between neurons and target cells in the nervous system. They play a crucial role in the communication and function of the brain and body.
Nicotinamide Adenine Dinucleotide: Nicotinamide adenine dinucleotide (NAD) is a coenzyme found in all living cells that plays a crucial role in various metabolic processes, including energy production, cellular signaling, and DNA repair. It is a key component in the electron transport chain and is involved in numerous redox reactions within the body.
Optical Activity: Optical activity is the ability of certain molecules to rotate the plane of polarized light as it passes through a solution containing those molecules. This phenomenon is directly related to the concept of chirality, where molecules can exist in two non-superimposable mirror-image forms, known as enantiomers.
Pro-R Hydrogen: The pro-R hydrogen refers to the specific hydrogen atom on a chiral carbon that is positioned on the right side of the molecule when viewed from the front. This orientation is crucial in understanding the concept of chirality and the significance of chiral environments in nature.
Prochiral Substrates: Prochiral substrates are molecules that possess a plane of symmetry, meaning they can be converted into chiral products through a chemical reaction. These substrates lack a stereocenter but have the potential to generate one upon transformation.
Proteins: Proteins are large, complex biomolecules composed of amino acids that play crucial roles in the structure and function of living organisms. They are essential for a wide range of biological processes, including catalyzing chemical reactions, transporting and storing other molecules, providing structural support, and participating in immune responses.
Receptor Interactions: Receptor interactions refer to the dynamic and specific binding of molecules, such as hormones or neurotransmitters, to their corresponding receptors on the surface or within cells. These interactions trigger signaling cascades that elicit various physiological responses in the body, and are crucial for understanding the mechanisms behind chiral environments and the role of chirality in nature.
Stereochemistry: Stereochemistry is the study of the three-dimensional arrangement of atoms in molecules and how this arrangement affects the chemical and physical properties of the substance. It examines the spatial orientation of atoms and their relationship to one another, which is crucial in understanding many organic chemistry concepts.
Stereoisomers: Stereoisomers are molecules that have the same molecular formula and connectivity, but differ in the three-dimensional arrangement of their atoms in space. This spatial arrangement of atoms leads to different physical and chemical properties, even though the atoms are connected in the same way.
Thalidomide: Thalidomide is a synthetic drug that was initially marketed as a sedative and anti-nausea medication, but its use was later banned due to its devastating effects on fetal development, causing severe birth defects. This term is particularly relevant in the context of understanding chirality and the importance of molecular handedness in nature and chiral environments.