MEDICAL CHEMISTRY
Department of Medical Chemistry, Molecularbiology and Pathobiochemistry
First Semester
credits: 6
Director of the course:
Prof. Gábor Bánhegyi M. D., Ph. D., D. Sc.
Description of the curriculum
The principal aim of the course is to prepare students for the understanding of Biochemistry and Molecular Biology. This requires a firm knowledge
of the basics of general, organic and inorganic chemistry.
I. General Chemistry
Structure of atoms, ions and molecules. Chemical bonds
Relation of atomic radius, ionization energy, electron affinity and electronegativity to the periodic table. Ionic bond, ion radius, ions.
Covalent bonding, and bonds, hybrid orbitals, hybridization of carbon. Electron pair repulsion, geometry of molecules, bond angle.
Molecular orbital theory.
Polar covalent bonds. Molecules composed of more than two atoms. Coordinative bond. Structure and geometry of ions. Metallic bonding. Interactions between molecules: electrostatic interactions, van der Waals and hydrogen bonds. Structure of water, its properties.
Physical states. Types of crystals, characteristic crystal lattices.
Solutions, laws of aqueous solutions, their biological and medical aspects
Solute, solvent, solution. The solution process. Solubility of ions in water, dissociation. Enthalpy of hydration. Concentration, % and
molar concentration, normality, molality, molar fraction. Saturated solutions. Solubility, partition, solubility product. Demonstration on
calculation problems. Laws of dilute solutions. Vapor pressure, freezing point, boiling point of pure solvents. Vapor pressure of
solutions, Raoult’s law. Freezing point depression and boiling point elevation of aqueous solutions. Osmotic pressure, dependence on
temperature, solute concentration and ionic dissociation. Biological and medical importance of osmosis.
Electrolytes
Electrolytes, degree of dissociation and the ionization constant, their correlation. Conductance of electrolytes, specific and equivalent
conductance of strong and weak electrolytes. Acid-base theories. The Arrhenius theory. Classification of acids and bases, their
anhydrides. The Bronsted-Lowry concept. The Lewis concept (e.g. coordination compounds). Acidic strenght and the molecular
structure. The ionization of water. Water product, definition of pH and pOH. The pH scale. Calculation of pH for strong electrolytes.
The effect of strong acids and bases on the ionization of weak acids and bases, respectively. The effect of strong acids and bases on the
salts of weak acids and bases. Buffers, calculation of pH of buffers. Buffers of polyprotic acids. Buffers of physiological importance. The
carbonic acid/hydrogencarbonate buffer.
Buffer capacity. Acid-base indicators. Titration curves of strong and weak electrolytes. The selection of indicator for titrations. The
amphoteric character. Basic and acidic salts. Double salts, complexes. Geometry of complexes, chelates. Reaction of salts with water
(hydrolysis).
Electrochemistry
Redox processes. Oxidation number, its definition. redox equations. The electrode potential, its explanation. Normal and standard
potentials. Galvanic cells, Nernst equation. Concentration cells, the principle of electrometric pH measurement. Non-polarizable
electrodes, their utilization in practice. Biological redox potential, redox electrodes. The application of redoxi potential for biological
processes, the principle of mitochondrial energy production. Electrolysis.
Thermodynamics
Chemical thermodynamics. Internal energy and enthalpy, reaction heat, standard enthalpy. Hess’ law. Combustion heat, atomic and
molecular enthalpy of formation. Bonding energy. The I. and II. laws of thermodynamics, entropy, free energy and free enthalpy.
Relation between electromotive force and free enthalpy change. Exergonic and endergonic processes. The equilibrium constant. The
direction of the processes and its relation to free energy change.
Chemical kinetics
Reaction kinetics, rate of reaction, order and molecularity. Half-time of reactions. The van’t Hoff rule. Activated complex, transition
state, activation energy. The Arrhenius equation. Catalysis, catalysts. Reversible processes, the law of mass action, equilibrium constant
and its relation to free energy change. Consecutive reactions, the importance of rate-limiting steps in metabolic processes.
II. Inorganic chemistry
Properties of non-metals
Group of halogens, their biological significance. Oxygen group, oxygen, free radicals containing oxygen, air, air pollution, ozone. Sulfur,
its compounds. The nitrogen group. Nitrogen, its important inorganic compounds. Nitrogen cycle. Phosphorus and its compounds.
Carbon group, carbon and its important inorganic compounds. The air polluting effect of carbon dioxide. Hydrogen and noble gases.
Inorganic compounds of medical importance.
Properties of metals
Alkali metals and their compounds. Alkali earth metals and their compounds, the biological significance of calcium and magnesium.
Earth metals. Heavy metals and their biological importance. Precious metals. Medically important metals and metal-containing
compounds.
III. Organic chemistry
General properties of organic compounds
Introduction, definition of organic compounds, their composition. Homologous series, constitution, constitution isomerism.
Classification according to carbon skeletons and functional groups. Characterization of bondings in organic compounds, bonding
energy, distance of atoms, dipole moment. Apolar and polar character, inductive and inductomeric, mezomeric and electromeric effects.
The vectorial character of dipole moment. Optical isomerism: structural principles of rotation. Chirality, chiral carbon atoms,
configuration, enantiomers. Principle of relative and absolute configuration. Projected formulas. Compounds with more than one chiral
center: diastereomerism, mezo-forms. Separation of optical isomers.
Classification of hydrocarbons based on their carbon backbone
Requirements for acknowledgement of the semester
(1) Participation in the laboratory practicals is obligatory; students should sign the attendance sheets at the end of the practicals. In case of more than
three absences from the practicals for any reason, the semester will not be acknowledged and the student is not going to be allowed to sit for the
semifinal exam. Missed practicals can be completed only in the same week at another group; certificate from the host teacher should be presented by
the student to the assigned teacher.
(2) It is compulsory to pass both midterm examinations; see next paragraph for details.
Midterm examinations
Two midterm written examinations will be held in weeks 6 and 12 of the semester, respectively, during regular laboratory practicals.
Midterm tests consist of four theoretical questions (10 points each) and four problems (calculations; 10 points each). The material of midterm I
covers that of lectures given in the first 5 weeks, while midterm II is based on the lecture material of weeks 6-11. Midterm tests will be evaluated by
lab teachers and marked as 0, 2, 3, 4 or 5. These ’midterm bonus points’ are added to the scores achieved at the semifinal exam (see below).
Grading of midterms (total scores including points obtained from lab reports):
0 – 40 points: 0
41 – 50 points: 2
51 – 60 points: 3
61 – 70 points: 4
71 or more points: 5