Medicinal chemistry is an interdisciplinary research area that incorporates different branches of chemistry and biology in the research for better and new drugs, focusing on the discovery and design of new therapeutic chemicals and their development into medicines.
Conformational isomers are different arrangements of atoms that can be converted into one another by rotation about single bonds.
The primary objective of medicinal chemistry is to discover, design, and develop new drugs that are effective and safe for treating diseases.
Para and meta Hydroxy Benzoic acids are considered inactive in terms of antibacterial activity.
8-Hydroxyquinoline is a compound that acts as an antibacterial and antifungal agent by complexing with iron or copper.
(-)-Adrenaline is the enantiomer of adrenaline that is biologically active and plays a crucial role in the fight-or-flight response, enhancing the body's ability to respond to stress.
Intermolecular hydrogen bonding occurs between two or more molecules of the same or different compounds, leading to an increase in boiling point and molecular weight of the compound, thus requiring more energy for vaporization.
Chirality refers to the property of a compound that has one asymmetric center, leading to the existence of two enantiomers that can interact differently with biological systems.
The melting point (MP) of Ephedrine is 37-39 degrees Celsius.
(+)-Adrenaline is the enantiomer of adrenaline that is less biologically active compared to its counterpart and is generally associated with its synthetic form.
The drug discovery stage involves finding a lead by choosing a disease, selecting a drug target, identifying a bioassay, finding a lead compound, and isolating and purifying the lead compound if necessary.
Stereochemistry affects pharmacological properties because any change in stereospecificity of a drug can influence its pharmacological activity.
Chelation/Complexation refers to the formation of a complex between drug molecules and a complexing agent, which prevents the drug from crossing natural membrane barriers, rendering it biologically ineffective.
Free drug (Df) is the portion of the drug that is not bound to plasma proteins and is available to exert a therapeutic effect.
Medicinal Chemists can make new compounds, determine their effects on biological processes, alter the structure for optimum effect and minimum side effects, and study the uptake, distribution, metabolism, and excretion of drugs.
The solubility of a substance at a given temperature is defined as the concentration of the dissolved solute, which is in equilibrium with the solid solute. It depends on the nature of solute and solvent as well as temperature, pH, and pressure.
The application of Classical Bioisosteres in drug design involves replacing a functional group with another that has similar physical or chemical properties to improve drug efficacy or reduce side effects. For example, replacing the -NH2 group in Carbutamide with a -CH3 group in Tolbutamide.
Halogens are a group of elements in group 17 of the periodic table, including chlorine (Cl), fluorine (F), bromine (Br), and cyanide (CN). They are known for their reactivity and tendency to form salts.
Physical properties of a drug are responsible for its pharmacological or therapeutic action, influencing how the drug interacts with biomolecules.
The optimum bacteriostatic activity in quinones is associated with a redox potential of +0.03 volts, which is important when tested against Staphylococcus aureus.
Structural modification involves altering the structure of drug molecules to improve their solubility.
The melting point (MP) of Pseudoephedrine is 118-120 degrees Celsius.
Partition Coefficients are usually determined in vitro using 1-octanol as a lipid phase and a phosphate buffer of pH 7.4 as the aqueous phase.
The specific characteristics of non-classical bioisosteres include electronic properties, physicochemical properties of the molecule, spatial arrangement, and functional moiety for biological activity.
Isosterism is the concept introduced by Longmuir in 1919, which postulates that two molecules or molecular fragments with an identical number and arrangement of electrons should exhibit similar properties.
Ephedrine has the structure with the (E) configuration, while Pseudoephedrine has the (T) configuration.
Isosteres are molecules or molecular fragments that contain an identical number and arrangement of electrons, leading to similar properties.
Cationic quaternary ammonium compounds possess bactericidal activity, meaning they are effective in killing bacteria and are often used as disinfectants.
Riboflavin analogues are compounds that mimic the structure of riboflavin, with biological activity influenced by their redox potential. The standard reduction potential (E0) of riboflavin is -0.185 volts, while its analogue, dichlororiboflavin, has an E0 of -0.095 volts.
A surfactant is defined as a material that can reduce the surface tension of water at very low concentration.
Redox potential is a quantitative expression of the tendency that a compound has to give or receive electrons.
Chelation refers to the formation of a stable ring structure within a molecule due to intramolecular hydrogen bonding, frequently observed in organic compounds.
The correlation between redox potential and biological activity can only be drawn for compounds with very similar structure and properties.
Isomeric pairs differ in pharmacological activity due to their different physical properties, such as log P and pKa.
A side effect of Hydralazine, an antihypertensive agent, is the formation of anemia, which occurs due to the drug's chelation with iron.
Pseudoephedrine is soluble at 1 gram per 200 mL of water.
Complexation involves the formation of a complex between a drug and another molecule, which can enhance the drug's solubility.
Pharmacodynamic agents are drugs that act on various physiological functions of the body, including general anesthetics, hypnotics, sedatives, and analgesics.
Calcium with EDTA forms a complex that increases the permeability of the membrane.
An ether is an organic compound characterized by an oxygen atom bonded to two alkyl or aryl groups, typically represented by the functional groups -S- and -O-.
The atoms and molecules of organic substances are held together by various types of bonds such as hydrogen bonds, dipole-dipole interactions, and ionic bonds, which are involved in solubility.
A hydroxyl group is a functional group consisting of a hydrogen atom covalently bonded to an oxygen atom (-OH) and is characteristic of alcohols.
Log P influences the extent to which a drug binds to blood and tissue proteins, affecting its distribution and bioavailability.
Protein binding is the reversible binding of a drug to non-specific and non-functional sites on body proteins without showing any biological effect.
Chemical properties refer to how a drug reacts extracellularly through simple chemical reactions such as neutralization, chelation, and oxidation.
The Partition Coefficient is defined as the equilibrium constant of drug concentration for the unionized molecule in two phases, specifically the ratio of drug concentration in lipid to drug concentration in water.
Lower concentrations of surfactants enhance the rate of absorption by reducing surface tension, while higher concentrations reduce the rate of absorption.
Natural compounds are materials obtained from both plant and animal sources, such as vitamins, hormones, amino acids, antibiotics, and alkaloids.
Ephedrine is soluble at 1 gram per 20 mL of water.
Equilibrium in Complexation describes the reversible relationship between free drug and drug complex, where the drug can exist in both states.
Solubility depends on the nature of the solute and solvent, along with factors such as temperature, pH, and pressure.
pH - pKa = log [ionized/unionized]
Log P is inversely related to aqueous solubility; higher log P values typically indicate lower solubility in water.
17-ß oestradiol is a natural estrogen hormone primarily responsible for the regulation of the female reproductive system.
Bioisosterism is defined as compounds or groups that possess near or equal molecular shapes and volumes, approximately the same distribution of electrons, and which exhibit similar physical properties.
Examples of univalent atoms and groups include Cl, Br, I, CH3, NH2, -OH, and -SH.
Weak bases are more lipid soluble at alkaline pH because they are in an uncharged form, which allows them to pass more readily through biological membranes.
Non-infectious diseases are disorders caused by genetic malfunction, environmental factors, stress, or aging, including conditions like diabetes, heart disease, and cancer.
Ionization imparts good water solubility to the drug, which is essential for binding to receptors and facilitating drug action.
Salicylic acid is a compound known for its antibacterial activity, characterized by its hydroxy and carboxylic acid functional groups.
Acetylcholine is a neurotransmitter that can exist in different conformations, influencing its biological activity.
Protein binding refers to the percentage of total plasma concentration of a drug that is bound to plasma proteins, affecting the drug's availability and action.
Stereoisomers are isomers that have the same bond connectivity but different arrangements of groups or atoms in space.
Undesirable side effects refer to adverse effects that occur when drugs bind to metal ions, potentially leading to toxicity or nutrient deficiencies.
A hydrogen bond is a special dipole-dipole interaction between the hydrogen atom in a polar bond (such as N-H, O-H, or F-H) and an electronegative atom (O, N, or F).
Surfactants are employed to improve the solubility of drugs by reducing surface tension and enhancing dispersion.
Conformation significantly affects the biological activity and interaction of drug molecules, influencing their efficacy and mechanism of action.
Log P influences the affinity of a drug to bind to enzymes and receptors, impacting its pharmacological activity.
Compounds capable of forming hydrogen bonds are typically soluble in water.
Solubility is crucial for pharmacists as it governs the preparation of liquid dosage forms and ensures that the drug is in solution for effective absorption and biological activity.
Hydrogen bonding is classified into two types: intermolecular and intramolecular.
For isosteres to be isoelectric means that they should possess the same total charge.
Thiopentone sodium has a chloroform/water partition coefficient of about 100, indicating its high lipid solubility.
H-bonding increases surface tension and viscosity due to the cohesive forces between molecules, leading to greater resistance to flow.
Trivalent atoms are atoms that form three bonds, and representative groups include -CH=, -N=, -P=, -As=.
Ring equivalents are structures that can mimic cyclic compounds, with examples including -CH=CH-, -S-, -O-, -NH, -CH2-.
The rate of drug absorption is directly proportional to the concentration of the drug in its absorbable ionized form, rather than the concentration at the absorption site.
Conformers can be interconverted by rotation about single bonds.
Optical isomers are chiral compounds that exist as two enantiomers, which have identical chemical and physical properties but may exhibit different physiological activities due to their interaction with biological receptors.
The staggered conformation refers to a specific arrangement of atoms in acetylcholine where the atoms are positioned to minimize steric hindrance.
The factors affecting Partition Coefficient include pH, co-solvents, surfactants, and complexation.
Fully eclipsed describes a conformation where atoms are directly aligned with each other, resulting in maximum steric hindrance.
The rate of absorption is proportional to the concentration of free drug molecules, meaning that higher concentrations facilitate greater diffusion of the drug.
The Partition coefficient, P, is a dimensionless value that indicates the lipophilicity of a compound.
Hydrogen bonds are weak bonds resulting from unequal sharing of electrons within a covalent bond, denoted as dotted lines.
Phenobarbital forms a non-absorbable complex with polyethylene glycol-4000.
Complexation reduces the rate of absorption of the drug but does not affect the overall availability of the drug.
Yes, the Partition Coefficient can be predicted using computational models.
Drugs must be in solution form to effectively interact with receptors in the body, which is essential for their pharmacological activity.
Ring structures are cyclic compounds with atoms bonded in a loop, while noncyclic structures have a linear or branched arrangement without closed loops.
Log P determines the permeability of a drug through biological membranes, affecting its absorption and distribution.
The trans isomer of diethylstibesterol exhibits significant estrogenic activity, while the cis isomer has only 7% of the activity of the trans isomer.
Examples of bivalent atoms and groups include R-O-R, R-NH-R, R-S-R, RCH2R, -CONHR, -COOR, and -COSR.
Ionization refers to the process of protonation or deprotonation resulting in charged molecules, affecting the drug's ability to exist in ionized or unionized states.
The Partition Coefficient is a measure of a drug's distribution between water and lipid phases, indicating its ability to permeate cell membranes.
Partition Coefficient is a ratio that describes how a drug distributes between two immiscible solvents, indicating its lipophilicity or hydrophilicity.
Dissociation Constant is a measure of the strength of an acid or base in solution, indicating the extent of ionization of the drug.
The biochemical modification of pharmaceutical substances by living organisms, often through enzymatic activity, to facilitate their elimination from the body.
Albumin is the most significant protein involved in drug binding, comprising more than half of blood proteins.
The ability of a drug to bind to proteins depends on whether it is a weak or strong acid, base, or neutral, allowing it to bind to single blood proteins or multiple proteins.
Stereochemistry is the study of the three-dimensional nature of molecules, focusing on chiral molecules and their spatial arrangements.
The partition coefficient is used in combination with the pKa to predict the distribution of a drug in biological systems, influencing absorption, excretion, and penetration of the CNS.
Intramolecular Hydrogen bonding is a type of hydrogen bonding that occurs within two atoms of the same molecule, often leading to the formation of cyclic structures.
Drug design focuses on identifying structure-activity relationships (SARs), identifying the pharmacophore, and improving target interactions and pharmacokinetic properties.
The Partition Coefficient influences drug transport and distribution by determining how a drug reaches the site of action from the site of application.
The log P value of a drug can be related to factors such as absorption, excretion, and penetration of the CNS, with lower values generally preferred to reduce toxicity and nonspecific binding.
Enantiomers may have different physiological activities because one may achieve a three-point attachment with its receptor molecule, while its enantiomer can only achieve a two-point attachment, affecting their efficacy and metabolism.
Key steps in drug development include patenting the drug, conducting preclinical trials, designing a manufacturing process, carrying out clinical trials, registering and marketing the drug, and generating profit.
Non-classical bioisosteres are functional groups that do not obey the steric and electronic definitions of classical isosteres and possess dissimilar valence electron configurations.
Cosolvents, such as ethanol, sorbitol, PPG, and PEG, are substances used to enhance the solubility of drugs in a solution.
Intramolecular Hydrogen bonding can decrease the boiling point of compounds, such as salicylic acid, by stabilizing the molecular structure.
Gauche conformation refers to a specific arrangement where substituents are 60 degrees apart, affecting the molecule's interactions and stability.
The redox potential of a system may be calculated using the equation E=E0 + 0.0592/n log[conc. of reductant /conc. of oxidant].
Medicinal chemistry combines expertise from chemistry and pharmacology to identify, develop, and synthesize chemical agents with therapeutic uses and to evaluate the properties of existing drugs.
H-bonding increases the boiling and melting points of substances due to the additional energy required to break these bonds.
Log P is the logarithm of the Partition coefficient, widely used as a measure of lipophilicity in drug development.
Synthesis compounds are either purely synthesized or synthesized versions of naturally occurring compounds, like morphine and cocaine, often created to reduce costs.
1-octanol is used because it has both polar and nonpolar regions, making the partitioning behavior easy to measure, and Po/w often correlates with many biological properties.
Drug/protein complex (Dp) is the portion of the drug that is bound to plasma proteins, influencing the pharmacokinetics and pharmacodynamics of the drug.
H-bonding enhances the water solubility of compounds by allowing them to interact more favorably with water molecules.
An example of replacing -OH with -SH in drug design is the transformation from Guanine (which has an -OH group) to 6-Thioguanine (which has an -SH group), showcasing how bioisosteric replacements can modify drug properties.
The strength of acids can be influenced by H-bonding, as stronger H-bonding can stabilize the conjugate base, increasing acidity.
A carbonyl group is a functional group composed of a carbon atom double-bonded to an oxygen atom (C=O) and is a key feature in several classes of organic compounds, including aldehydes and ketones.
Classical Bioisosteres are entities that have similarities in shape and electronic configuration with the atoms, groups, or molecules they replace.
Weak acid Aspirin is readily absorbed in the stomach because it is in the un-ionized form (99%) at a pH of 1.0.
Catechol is a dihydroxybenzene compound with two hydroxyl groups (-OH) attached to a benzene ring, commonly used in chemical synthesis and as a reducing agent.
Tropicamide, an anticholinergic drug, has a pKa of 5.2 and must be buffered to pH 4 to achieve more than 90% ionization.
Dimercaprol is a chelating agent used as an antidote for metal poisoning, particularly effective against arsenic and lead.
Solubility is the ability of a substance to dissolve in a solvent, affecting the drug's effectiveness and absorption.
Redox Potential is a measure of the tendency of a chemical species to acquire electrons and thereby be reduced, influencing drug reactivity and metabolism.
The chemical nature of surfactants, their concentration, and their effect on biological membranes and micelle formation.
Total plasma concentration (Dt) is the sum of free drug (Df) and drug/protein complex (Dp), indicating the overall presence of the drug in the bloodstream.
Semi-synthesis compounds are drugs that cannot be purely synthesized or isolated from natural sources cost-effectively, using natural intermediates for their synthesis, such as semi-synthetic penicillins.
Po/w refers to the partition coefficient of a compound between octanol and water, and it is often used as a measure that correlates with various biological properties.
Diethylstilbestrol is a synthetic nonsteroidal estrogen that was prescribed to prevent pregnancy complications but was later linked to health risks.
The Partition Coefficient is a ratio that describes the distribution of a drug between lipid and aqueous phases, affecting drug transfer characteristics.
Phenobarbitone has a high lipid/water partition coefficient of 5.9.
When an acid or base is 50% ionized, pH equals pKa.
Aliphatic alcohols have bactericidal activity, allowing them to effectively kill bacteria, making them useful as antiseptics and disinfectants.
Thiopentone sodium is used as an ultra-short acting barbiturate due to its high lipid solubility.
% ionization = 100 / [1 + 10^(pH - pKa)]
Non-diseases refer to conditions that do not involve a disease process, such as pain mitigation through analgesics, contraception for pregnancy prevention, and anesthesia.
Penicillamine is a chelating agent that forms 1:1 and 1:2 chelates with metals like copper, used in treating conditions such as Wilson's disease.
The term is 'enantiomers', which are a type of stereoisomer that are mirror images of each other and can exhibit different biological activities and potencies.
Hexylresorcinol exhibits antihelminthic activity, which means it is effective in treating infections caused by helminths (parasitic worms).
pH - pKa = log [unionized/ionized]
Antipyrin, also known as 1-phenyl-2,3-dimethyl-5-pyrazolone, is a compound with analgesic activity attributed to its ability to form hydrogen bonds.
Geometric isomerism is represented by cis/trans isomerism resulting from restricted rotation due to carbon-carbon double bonds or in rigid ring systems.
Weak acids are more lipid soluble at acidic pH because they are in an uncharged form, allowing them to pass more readily through biological membranes.
H-bonding plays a crucial role in the stability and structure of biological products, such as proteins and nucleic acids, influencing their function.
Infectious diseases are illnesses caused by outside agents such as bacteria, viruses, fungi, and parasites that can be transmitted from person to person.
Ionization influences drug absorption by affecting the drug's ability to cross biological membranes, with ionized forms typically being less permeable.
Optical and geometrical isomerism can significantly affect drug activity as different isomers may interact differently with biological targets, leading to variations in efficacy and safety.
Isosterism is the concept of replacing an atom or group in a drug molecule with another atom or group that has similar properties, influencing drug design and activity.
The solubility of a drug may be expressed in terms of its affinity/philicity or repulsion/phobicity for either an aqueous or organic solvent.
Hydrogen bonding plays a crucial role in the analgesic activity of Antipyrin (1-phenyl-2,3-dimethyl-5-pyrazolone), while its analog 1-phenyl-3-methyl-5-pyrazolone is inactive due to lack of effective hydrogen bonding.
The degree of ionization (a) indicates the extent to which a drug is ionized in an aqueous solution, influencing its solubility and absorption.
1-phenyl-3-methyl-5-pyrazolone is considered inactive because it does not effectively engage in hydrogen bonding, which is necessary for analgesic activity.
Quantitative Structure-Activity Relationship (QSAR) is widely used to predict the activity of drug molecules based on their chemical structure.
Phenytoin injection must be adjusted to pH 12 with Sodium Hydroxide to obtain 99.98% of the drug in ionized form.
Solubility is crucial as it determines the extent to which a drug can dissolve in body fluids, affecting its absorption and overall therapeutic effectiveness.
Barbituric acid is inactive because it is a strong acid, while 5,5 disubstituted Barbituric acid has CNS depressant action because it is a weak acid.
Log P can be measured using the shake flask method and the chromatographic method (HPLC).
Chemotherapeutic agents are drugs used to combat pathogenic organisms, including sulphonamides, antibiotics, antimalarial agents, antiviral drugs, and anticancer medications.
Log P can affect how well a drug is metabolized by P450 enzymes, influencing its bioavailability and clearance from the body.
Ionization affects the solubility and permeability of drugs, influencing their absorption and distribution in the body. Uncharged forms of drugs are more lipid soluble and can more readily pass through biological membranes.
Functional groups and structural arrangements help determine the lipophilic (fat-loving) or hydrophilic (water-loving) character of drug molecules.
Phenol and cresol are known for their disinfectant action, effectively killing bacteria and other pathogens on surfaces.
Tetravalent atoms are atoms that form four bonds, and representative groups include =C=, =N=, =P=.
The ionization of a drug depends on its pKa and the surrounding pH, which influences whether the drug is in an ionized or unionized form.
1:1 and 1:2 chelates refer to the stoichiometry of the metal-to-chelator ratio in the complex formed, indicating how many chelator molecules bind to a single metal ion.
Complexation is the process of forming a complex between a drug and another molecule, which can modify the drug's solubility, stability, and bioavailability.
Protein Binding is the degree to which drugs attach to proteins in the blood, affecting their distribution, free concentration, and therapeutic efficacy.
H-bonding can affect the spectroscopic properties of a substance by altering the energy levels of electronic transitions, leading to shifts in absorption and emission spectra.
Solubility is governed by solvent-solvent, solute-solute, and solvent-solute interactions.
The two types of Bioisosteres are Classical bioisosteres and Non-classical bioisosteres.
Bile salt solutions at approximately physiological concentration enhance the dissolution rate of poorly water-soluble drugs like griseofulvin and hexestrol through a micellar solubilization effect.
Physicochemical properties influence drug action by determining how drug molecules interact with physiological processes, affecting their pharmacologic or therapeutic effects.
The unionized form of a drug is more capable of crossing cell membranes, allowing for better absorption into cells.
Surface Activity refers to the ability of a substance to alter the surface properties of a liquid, which can affect drug formulation and delivery.
H-bonding is key in drug-receptor interactions as it can enhance binding affinity and specificity between drugs and their targets.
Chelates, such as Dimercaprol and Penicillamine, bind to toxic metals in the body, facilitating their excretion and reducing their harmful effects.
Bioisosterism refers to the concept of replacing one part of a drug molecule with another that has similar physical or chemical properties to improve efficacy or reduce side effects.
Hydrogen bonding is significant because it affects the binding affinity of drugs to their targets, influencing their pharmacological activity.
Hydrogen Bonding is an attractive interaction between a hydrogen atom bonded to an electronegative atom and another electronegative atom, influencing drug solubility and stability.
Ionization of a drug refers to the process of the drug molecule gaining or losing protons, affecting its solubility and absorption in different pH environments.
Designing drugs with the lowest possible log P is significant to reduce toxicity, nonspecific binding, and improve bioavailability.
