CHEMISTRY IN DAILY LIFE: A STUDY NOTE

CHEMISTRY IN ACTION (3Marks) SECTION A Drug: Chemicals of low molecular mass which interact with macromolecular targets and produce a biological response. Ex. Paracetamol. Medicine: Drugs which cure diseases i.e. which cause therapeutic biological response . Ex. Equanil. Antacid: Chemical substances which remove the excess acid and raise the pH to appropriate level in stomach . Ex. Mg(OH)2. Antihistamines/ antiallergic drugs: are the drugs used to control the allergy effects produced by histamines. Ex. Chloropheniramine. Tranquilizers/psychotherapeutic drugs: Chemical substances used for treatment of stress, mild and severe mental diseases. These relieve anxiety, irritability or excitement by inducing a sense of well being. Ex. Equanil. Analgesics: Chemical substances used to relieve pain without causing impairment of consciousness, mental confusion, incoordination or paralysis or some other disturbances of nervous system. Ex. Aspirin. Antidepressant drugs: Chemical substances used for mood changing or to counteract the effect of depression. Ex. Iproniazid. Pathogen: Any organism that causes disease. Ex. Bacteria, viruses Allosteric site: The site of an enzyme other than active site to which a drug binds. Receptors: Proteins that are crucial to body’s communication process which are mainly embedded in the cell membrane with their active site projecting outside. Antagonists: Drugs that inhibit natural function of receptors by binding to their active sites. Antipyretic: A chemical substance used to lower body temperature when there is fever . Ex. Paracetamol. SECTION - B What causes depression? What drug do you suggest for counteracting depression? How does it decrease depression? Noradreniline is one of the neurotransmitters. Decrease in the level of noradriniline lowers signal sending activity and this leads to depression. Iproniazid, an antidepressant drug is used for counteracting depression. It inhibits the enzymes which catalyses the degradation of noradreniline. If the enzyme is inhibited, this neurotransmitter is metabolized and can activate its receptor for longer periods of time, thus counteracting the effect of depression. 2. What is a hypnotic? Give an example. Sleep producing chemical substances. Ex. Luminal 3. What are barbiturates? Give an example. Tranquilzers derived from barbituric acid. Ex. Luminal 4. Describe two types of analgesics with an example for each. Non-narcotic/non–addictive analgesics: Analgesics which relieve pain without causing unconsciousness or without inducing sleep. Ex. Aspirin. Narcotic drugs: Analgesics which relieve severe pain by causing unconsciousness or inducing sleep. Ex. Heroin. What for all can aspirin be used? What is its insignificance? Aspirin can be used to inhibit synthesis of prostaglandins which stimulate inflammation in the tissue and cause pain. to relieve pain due to arithritis. as an antipyretic to prevent platelet coagulation to prevent heart attack. There are some complications in using aspirin it is toxic to lever some times causes bleeding from stomach wall and gastric irritant. How is a disease caused? Or What causes infection? A breach (failure) defence mechanism allows the pathogen to reach tissues and this causes infection. Invasion and multiplication of an organism in the infected host causes disease due to destruction of normal cell metabolism. In addition toxins produced by microbes may adversely affect the tissues or organs of the host. State three ways of controlling microbial diseases. by a drug which kills the organism in the body (bactericidal) by a drug which inhibits the growth of organism (bacteriostatic) by increasing immunity and resistance to infection of the body. Name an important antiseptic added to toilet soap. Bithional. Give a point of difference between a bactericidal and bacteriostatic with an example each. Bactericidal: antibiotics which kill organisms in the body Ex. Penicillin Bacteriostatic: antibiotics which inhibit the growth of microorganisms in the body. Ex.Tetracycline. Antibiotic therapy is nothing but “setting one thief against another”. Explain. Chemical substances produced by micro organisms (bacteria, fungi and mould) that inhibit the growth or even destroy micro organisms are called antibiotics. Ex. Penicillin Antibiotics themselves are product of microbial growth and hence it is nothing but setting one thief against another. Describe broad spectrum antibiotics and narrow spectrum antibiotics with an example each. Broad spectrum antibiotics: Antibiotics which are effective against several different microorganisms and thus capable of curing several infections . Ex. Tetracycline. Narrow spectrum antibiotics: Antibiotics which are effective only against limited number of types of harmful microorganisms. Ex. Penicillin. Name two antioxidants used to preserve wine and beer. SO2 and sulphites. Name the first artificial sweetener. For which disease is it a life saver? Saccharin is the first artificial sweetener. It is a life saver for diabetes. Some chemicals which do not have any nutritive value of food are added to food stuff. What are those? Are they harmful to us? If so how? Those are artificial sweeteners. Yes they are harmful to us. They do not have any nutritive value, but our digestive system (stomach) works on it and hence if taken in large quantity it weakens digestive system. Some chemicals which do not have any nutritive value of food are added to food stuff to improve their appearance . What are those? Are they harmful to us? If so how? Those are edible colors. Some of them are harmful to us. Azodyes are harmful for young children and asthma patients. Sleeping pills are recommended by doctors to the patients suffering from sleeplessness but it is not advisable to take its doses without consultation with the doctor . Why? Most of the drugs taken in higher doses than recommended may cause harmfull effect and act as poison. Therefore a doctor should always be consulted before taking medicine. With refernce to which classification has the statement “ rantidine is an antacid” has been give. ? This classification refers to the classification according to pharmacological effect of the drug because any drug which will be used to counteract the effct of excess of acid in stomach will be called antacid. Why do you require artificial sweetening agents? Artificial sweetneres do not have any nutritive value. Natural sweetners add to calorie intake. So when we want the eatables to become sweet but should not add to calorie we require artificial sweetening agents. Write chemical equation for preparing sodium soap from glyceryl oleate and glyceryl palmitate.Structural formulae of these compounds are given below (i) (C15H31COO)3 C3H5 – Glyceryl palmitate (ii) (C17H32COO)3C3H5 – Glyceryl oleate. C15H31COOCH2 CH2OH C15H31COOCH + 3NaOH 3 C15H31COONa + CHOH C15H31COOCH2 Sodium palmitate (soap ) CH2OH Glyceryl palmitate Glycerol C17H32COOCH2 CH2OH C17H32COOCH + 3NaOH 3 C17H32COONa + CHOH C17H32COOCH2 Sodium oleate (soap ) CH2OH Glyceryl oleate Glycerol SECTION C CBSE 2008 Mention one use each of following drugs Rantidine (ii) Paracetamol (iii) Tincture of iodine (i) Rantidine : used as an antihistamine (ii) Paracetamol : used as an antipyretic. (iii) Tincture of iodine : used as an antiseptic CBSE March – 2007 Describe and illustrate with an example each. (i) Detergent (1Mark) Sodium or Potassium salts of sulphonic acids obtained from petroleum products or ammonium salts with long hydrocarbon chain used for cleaning are called detergents Ex. Sodiumalkylbenzene sulphonate. Detergents are advantageous to soaps . They work with hard and soft water. Three types of detergents are (i) anionic detergents (ii) cationic detergents (iii) non-ionic detergents. CBSE March – 2006. Define the following and give one example each.(i) antipyretics (ii) antibiotics (2Marks) (i) Antipyretics: The chemicals used to lower body temperature. Ex. Paracetamol (ii) Antibiotics: Chemical substances produced by micro organisms (bacteria, fungi and mould) that inhibit the growth or even destroy micro organisms. Ex. Penicillin OR A chemical substance produced wholly or partly by chemical synthesis which in low concentration inhibits the growth or destroys microorganisms by intervening in their metabolic processes. CBSE March – 2005 Describe the following with an example each.(i) antimicrobials (ii) antioxidants (2marks) (i) antimicrobials: The chemical substances used to kill or control growth of microbes are called as antimicrobials. Ex. Dettol (ii) antioxidants: The food additives used to prevent or retard oxidation of food items and thereby help in food preservation are called as antioxidants. Ex. BHT (Butylated Hydroxy Toluene) CBSE March – 2004 Describe the following example in each case. (i) Antioxidants (ii) Biodegradable detergents. Or (i) Edible colors (ii) antifertility drugs (iii) preservatives. (3 Marks) (ii) Biodegradable detergents: Detergents with un branched short chained hydrocarbon part are decomposable by bacteria and are called as biodegradable detergents. OR (i) Edible colors: colored chemical substances added to food to improve their appearance. Ex. Tetrazine. But some food dyes are harmful. (iii) antifertility drugs; The chemical substances which are used to check pregnancy in women or birth control drugs or oral contraceptives are called ant fertility drugs. Ex. Norethindrone. CBSE 2002 Give one important use each of the following in pharmacy.(i) Equanil (ii) Morphine(2 marks) (i)Equanil:as a tranquilizer in controlling depression and hyperetension. (ii) Morphine: used as a narcotic analgesic to relieve pain and produce sleep. CBSE 2001 What is the role of bithional in toilet soaps? (1 Mark) Bithional acts as an antiseptic. CBSE 1999 What are antibiotics?Name any two antibiotics which are specific for certain diseases. (2) Antibiotics: Chemical substances produced by micro organisms (bacteria, fungi and mould) that inhibit the growth or even destroy micro organisms. Ex. Chloamphenicol for typhoid, CBSE 1996 What are micelles ? Give an example of a micellar system. Radial arrangement of many soap molecules with the negative head outwards and hydrophobic tail towards the centre with dirt particles when large quantity of soap is dissolved in water for cleaning is called as micelles. Ex. Soaps and detergents. SECTION - D (Higher order questions for high achievers) Write a short note on drug target interaction. Drug target interaction can be explained by considering drug enzyme interaction. Enzymes act as biocatalysts. Active site of enzyme holds the substrate molecule in a suitable position and attacked by the reagent effectively and chemical reaction takes place. Drugs inhibit the attachment of substrate on active site of enzymes in two different ways. (i).Competitive inhibitor drugs compete with the natural substrate for their attachment on the active sites of enzymes. (ii) Some drugs instead of binding to the active site , bind to the allosteric site of enzyme and hence change the shape of the active site in such a way that substrate can not recognize it. If the bond formed between an enzyme and an inhibitor is a strong covalent bond and can not be broken easily, then the enzyme is blocked permanently. The body then degrades the enzyme-inhibitor complex and synthesizes a new enzyme. 2. Give structural formula for Aspirin. What is its IUPAC name? COOH OCOCH3 IUPAC name: 2 – Carboxyphenylethanoate 3. Whenever a doctor prescribes a medicine of aspirin content directs patient not to take in empty stomach. Why? Aspirin contains a carboxylic acid group and hence when it interacts as a drug it causes acidity and higher acidity caused by it some times may lead to ulcers also. 4. What is meant by spectrum w.r.t microorganisms? The total range of microorganisms which can be killed by a particular antibiotic is referred to its spectrum. 5. What is an antioxidant? How does it preserve food? Give an example. The food additives used to prevent or retard oxidation of food items and thereby help in food preservation. These act as sacrificial materials i.e. these are more reactive towards than are the materials that they protect. They also reduce rate of involvement of free radicals in the aging process. In some cases they are least reactive towards oxygen and hence protect the material with which they are put. Ex. Dintrogen in chips packets. Ex. BHT(Butylated Hydroxy Toluene) 6. What is the chemical name and structure of the first popular artificial sweetening agent? Ortho-sulphobenzimide. SECTION - E EXERCISE QUESTIONS Why do we need to classify drugs in different ways ? Drugs: cause different pharmacological effect. interact with different molecular targets. act differently on biochemical processes. have different structures . Explain the term target molecules or drug targets as used in medicinal chemistry. Biomolecules with which drug molecules interact are called as target molecules or drug targets Name the macromolecules that are chosen as drug targets. Proteins, lipids, enzymes, nucleic acids, carbohydrates. Why should not medicines be taken without consulting doctors ? Doctors will recommend suitable and proper dose of drug after diagnosing the disease. If suitable drug is not taken and also drug taken in doses higher than recommended may cause harmful effect and act as a poison Define the term chemotherapy. Use of chemicals for therapeutic effect i.e. for curing diseases Which forces (ii) hydrogen bonding (iii) dipole-dipole interaction (van der Waals interaction) While antacids and antiallergic drugs interfere with the function of histamines, why do these not interfere with the function of each other? Antiallergic and antacid drugs do not work on the same receptor at a time i.e. they work on different receptors. Low level of noradrenaline is the cause of depression. What type of drugs is needed to cure this problem? Name two drugs. Antideppressant drugs are needed to cure this problem. E.g. (i) Iproniazid (ii) Phenelzine What is meant by the term “broad spectrum antibiotics”. Explain. Antibiotics which are effective against several different types of harmful micro organisms and thus capable of curing several infections are called broad spectrum antibiotics.. They are effective against both gram positive and gramnegative bacteria. Ex. Tetracycline, Chloamphenicol 10.How do antiseptics differ from disinfectants? Give one example of each. Antiseptics Disinfectantants Chemicals which kill or prevent Chemicals which kill or Chemicals which kill or prevent prevent the growth of the growth of microorganisms microorganisms when applied when applied to inanimate objects to living tissues i.e wounds, i.e floors,drainage systems, cuts,ulcers etc. instruments etc. Ex.0.2%Phenol ,Dettol 1% Phenol,.2 to 0.4 ppm Chlorine 11.Why are cimetidine and ranitidine better antacids than sodium hydrogen carbonate or magnesium hydroxide or Aluminum hydroxide? Sodium hydrogen carbonate or magnesium hydroxide or Aluminum hydroxide when administered in excess make stomach alkaline and trigger the production of even more acid. These chemicals only control the symptoms and not the cause. Histamine stimulates the secretion of pepsin and HCl acid in stomach. Cimetidine and ranitidine prevent interaction of histamine with the receptors present in the stomach wall. 12. Name a substance which can be used as an antiseptic as well as disinfectant. Phenol solution.(0.2% Phenol solution is used as an antiseptic and 1% Phenol solution is used as a disinfectant) 13.What are the main constituents of dettol? Chloroxyleneol and Terpineol. 14. What is tincture of iodine? What is its use? 2 to 3% Iodine in a mixture of water and alcohol is called tincture of iodine . It is used as an antiseptic to apply on fresh wounds. 15.What are food preservatives? Give an example. Harmless chemical substances added to food materials to prevent their spoilage. Ex. Sodium benzoate. 16.Why is use of aspartame limited to cold foods and drinks? Aspartame is unstable at cooking or at higher temperature 17. What are artificial sweetening agents? Give two examples. The food additives which are non-nutritive in nature and used as substitute for sugar .Ex. Saccharin, aspartame. 18.Name the sweetening agent used in the preparation of sweets for a diabetic patient. Saccharin 19.What problem arises in using alitame as artificial sweetener? When alitame is used as artificial sweetener controlling of sweetness of food is difficult. 20.How are synthetic detergents better than soaps? Synthetic detergents work both in hard and soft water but soaps do not work in hard water and work in only in soft water. 21.Explain the following terms with suitable examples. (i) Cationic detergents (ii) anionic detergents (iii) non- ionic detergents (i) Cationic detergents : Quaternary ammonium salts of amines with cationic part possessing a long hydrocarbon chain and a positive charge on Nitrogen atom and acetates, chlorides and bromides as anions. Here cationic part of the detergent involve in cleansing action. Ex. Cetyltrimethylammonium bromide. (ii) anionic detergents: Sodium salts of sulphonated long chain alcohols or hydrocarbonsin which anionic part of the detergents involve in cleansing action. Ex.Sodiumlaurylsulphate (iii) non- ionic detergents: Detergents which do not contain any ion in their constitution. Ex.Polyethyleneglycol stearate. 22. What are biodegradable and non-biodegradable detergents? Give one example of each. Detergents with straight chain hydrocarbon part can be degraded by bacteria and are called as biodegradable reagents. Ex. Trimethylsteryl ammonium bromide. Detergents with highly branched hydrocarbon part can not be degraded by bacteria and are called as non-biodegradable detergents. CH3 CH3 H3C – (CH – CH2 ) – CH - CH - C6H5SO3- Na+ Alkylbenzene sulphonate 23. Why do soaps not work in hard water? Hard water contains Ca2+ and Mg2+ ions . These ions form insoluble Ca/Mg soaps when Na/K soaps are dissolved in hard water. These insoluble soaps separate as scum in water and useless as cleansing agents. 24. Can you use soaps and synthetic detergents to check the hardness of water? If so how? Yes, soaps and detergents can be used to check the hardness of water. Soaps do not work in hard water and work only in soft water. Detergents work in both hard and soft water. 25. Explain the cleansing action of soaps. Soaps are Na/K salts of fatty acids. O - Na+ Soaps contain two characteristics groups. One is hydrophobic hydrocarbon tail and another is hydrophilic negative head. When soap is dissolved in water micelles are formed. Oil/grease droplet Radial arrangement of many soap molecules with the negative head outwards and hydrophobic tail towards the centre with dirt particles when large quantity of soap is dissolved in water for cleaning is called as micelles. Polar group 9nteracts with water and grease droplets are pulled into water and removal of dirt takes place. Micelles do not come together due to presence of negative sheath on them. 26. If water contains dissolved calcium hydrogen carbonate, out of soaps and synthetic detergents which one will you use for cleaning cloth? Why? Detergent because water containing dissolved calcium hydrogen carbonate is a hard water and hence it does work with soap for cleaning cloth. 28. Label the hydrophilic and hydrophobic parts in the following compounds. (i) CH3 (CH2) 10 CH2OSO3-Na+ (ii) CH3 (CH2) 15 N+(CH3)3Br_ CH3(CH2)16COO(CH2CH2O)n CH2CH2OH i) [CH3 (CH2) 10 CH2] [OSO3-Na+ ] (ii) [CH3 (CH2) 15] [N+ (CH3)3Br_] (iii) [CH3 (CH2)16C] [OO (CH2CH2O) n CH2CH2OH] Hydrophobic part Hydrophilic PREPARED BY:NAYAK UDAY D. P.G.T.IN CHEMISTRY,JNVCHIKMAGALURE MOB. NO:9449620408 1 NH SO2 CO