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Behavior can be influenced by a number of factors Further Reading beyond attitude purchase discount zestril line hypertension of the knee, including preconceptions about self and Barkley buy genuine zestril on-line arteria profunda femoris, R cheap zestril 2.5mg with visa pulse pressure in septic shock. Attention Deficit Hyperactivity Disorder: A others cost of zestril blood pressure readings low, monetary factors, social influences (what peers Handbook for Diagnosis and Treatment. New York: Guil- and community members are saying and doing), and dord Press, 1990. Driven to Distraction: Recog- about improving the public school system in their town, nizing and Coping with Attention Deficit Disorder from but if it means a hefty increase to their property taxes, Childhood through Adulthood. New York: Simon and they may vote against any improvements due to the po- Schuster, 1994. The Hyperactive Child, Adolescent, and Adult: At- supporter, showing that their actions (i. New York: attending parent-teacher organization meetings) are Oxford University Press, 1987. Cognitive therapy attempts to change irrational Further Information ways of thinking. One research study found that antismoking cam- Advertising, political campaigns, and other persuasive paigns targeted at teenagers can have a higher success media messages are all built on the premise that behavior rate when adolescent peers are used as instructors. Paula Ford-Martin The fields of social and behavioral psychology have researched the relationship between attitude and behav- ior extensively. The more psychologists can understand Further Reading the relationship between attitude and behavior and the Byrne, Donn and Robert A. The important social problems such as racism, gender bias, psychology of attitudes. It is also a key part of public health edu- cation initiatives, particularly in the case of preventive Attitudes and attitude change medicine. Campaigns promoting positive attitudes to- An attitude is a predisposition to respond cogni- wards prenatal care, abstinence from drug use, smoking tively, emotionally, or behaviorally to a particular cessation, sunscreen use, organ donations, safe sex, can- object, person, or situation in a particular way. In effect, social Attitudes have three main components: cognitive, af- marketing is “selling” attitudes and beliefs and ideally fective, and behavioral. The cognitive as- Changing behavior to influence attitudes pects of attitude are generally measured by surveys, inter- In 1955, clinical psychologist and educator George views, and other reporting methods, while the affective Kelly introduced his psychology of personal constructs. Behavior, on the other vidual looks at the world through his or her own unique hand, may be assessed by direct observation. Behavior does not always conform to a person’s feel- These constructs change and adapt as the individual is ings and beliefs. At the heart of may be suppressed because of a competing attitude, or in Kelly’s theory is the idea that individuals can seek new deference to the views of others who disagree with it. A experiences and practice and adapt new behaviors in classic theory that addresses inconsistencies in behavior order to change their attitudes (or constructs) towards the and attitudes is Leon Festinger’s theory of cognitive dis- world. He recommended that therapists encourage their sonance, which is based on the principle that people pre- patients to try out new behaviors and coping strategies; fer their cognitions, or beliefs, to be consistent with each he and others that followed frequently found that pa- other and with their own behavior. Inconsistency, or disso- tients would adapt these useful new behavior patterns nance, among their own ideas makes people uneasy and subsequently change their attitudes. For example, smokers forced to deal with the sometimes a result of social or peer pressure. While opposing thoughts “I smoke” and “smoking is dangerous” adult behavior generally follows from held attitudes, for are likely to alter one of them by deciding to quit smok- children, attitudes are often shaped by observed behavior. Test subjects ers and, to a degree, build their attitudes and beliefs from in hundreds of experiments have reduced cognitive disso- this learned behavior. There is, however, evi- quire many of their attitudes by modeling their parents’ dence of a direct link between self-esteem and attitude attitudes. People with low self-esteem are often not atten- uli is another method of attitude formation and one widely tive enough to absorb persuasive messages, while those used by advertisers who pair a product with catchy music, with high self-esteem are too sure of their own opinions soothing colors, or attractive people. The most easily ing, which utilizes rewards, is a mode of attitude forma- persuaded individuals tend to be those with moderate tion often employed by parents and teachers. Attitudes are levels of self-esteem, who are likely to pay a reasonable also formed through direct experience. It is known, in fact, amount of attention to what those around them say and that the more exposure one has toward a given object, remain open enough to let it change their minds. The medium of persuasion also influences attitude change (“the medium is the message”). Face-to-face One of the most common types of communication, communication is usually more effective than mass com- persuasion, is a discourse aimed at changing people’s at- munication, for example, although the effectiveness of titudes. The first any one component of communication always involves of these is the source, or communicator, of a message. The effects of persuasion be effective, a communicator must have credibility based may take different forms. Sometimes they are evident on his or her perceived knowledge of the topic, and also right away; at other times they may be delayed (the so- be considered trustworthy. In addition, people may often similarity between communicator and audience, the change their attitudes only to revert over time to their greater the communicator’s effectiveness. This is the original opinions, especially if their environment sup- principle behind politicians’ perennial attempts to por- ports the initial opinion. This practice has come to include dis- veloped by psychologist William McGuire, focuses on a tinguishing and distancing themselves from “Washing- chronological sequence of steps that are necessary for suc- ton insiders” who are perceived by the majority of the cessful persuasion to take place. They must then sage itself, the method by which the message is present- yield to the argument, and retain it until there is an oppor- ed is at least as important as its content. Attitude: Your Most Priceless Posses- provokes fear; and whether it presents its strongest argu- sion. New York: Cambridge University Press, present an identical message to two different groups, the 1986. The Psychology of Attitude Change and still vary because audience variables such as age, sex, Social Influence. Philadelphia: Temple University Press, and intelligence also affect attitude change. Some have at- tributed it to the superior verbal skills of females which may increase their ability to understand and process ver- Attraction, interpersonal bal arguments. Others argue that it is culturally deter- A favorable attitude toward, or a fondness for, an- mined by the greater pressure women feel to conform to other person. The effect of intelligence on attitude change is in- Both personal characteristics and environment play conclusive. According to another theory, a who come into contact regularly and have no prior nega- person will choose a partner who will enhance his or her tive feelings about each other generally become attracted own self-image or persona. Researchers generally ac- to each other as their degree of mutual familiarity and knowledge a specific set of courting or flirting behaviors, comfort level increases. Initially, first meet also determines how they will feel about each both men and women use varied repertoires of body lan- other. One is more likely to feel friendly toward a person guage to signal interest and/or availability. Women draw attention to themselves and opinions two people share, the greater the probabili- by tossing or playing with their hair, tilting their heads, ty that they will like each other. The first that disagreement on important issues decreases attrac- connection is generally made through eye contact, often tion.

At the same time purchase 10mg zestril amex blood pressure pregnancy, if you very strongly believe in any of these items buy 2.5mg zestril visa pulse pressure in septic shock, you just may have too much anxiety or depression buy cheap zestril 2.5 mg blood pressure bracelet. If you have any thoughts of suicide or utter hopelessness purchase on line zestril blood pressure 160100, you should consult your primary care physician or a mental health professional immediately. Chapter 1: Sorting Out Signs of Anxiety and Depression 11 Walking in Quicksand: Apprehensive and Blue Behavior If you were to follow a depressed or anxious person around, you might see some behavioral signs of their emotional turmoil. That’s because depression and anxiety on the inside affect what people do on the outside. For example, a depressed person may look tired, move slowly, or withdraw from friends and family; an anxious person may avoid socializing or have a trembling voice. Take the quiz in Worksheet 1-2 to see if your behavior indicates a problem with anxiety and/or depression. I feel compelled to repeat actions (such as hand washing, checking locks, arrang- ing things in a certain way, and so on). Even-numbered items are most consistent with anxiety, and odd-numbered items largely indicate depression. And, of course, like many people, you may have symptoms of both types of problems. In fact, some people primar- ily suffer from changes in appetite, sleep, energy, or pain while reporting few problematic thoughts or behaviors. These symptoms directly affect your body, but they’re not as easily observed by other people as the behavioral signs covered in the preceding section. Part I: Analyzing Angst and Preparing a Plan 12 Take The Sad, Stressed Sensations Quiz in Worksheet 1-3 to see if your body is trying to tell you something about your emotional state. The symptoms in this quiz can also result from various physical illnesses, drugs in your medicine cabinet, or even your three-cup coffee fix in the morning. Be sure to consult your primary care physician if you’re experiencing any of the symptoms in The Sad, Stressed Sensations Quiz. It’s always a good idea to have a checkup once a year and more frequently if you experience noticeable changes in your body. Although physical sensations overlap in anxiety and depression, even-numbered items in the quiz above are most consistent with anxiety, and the odd-numbered items usually plague those with depression. Reflecting upon Relationships When you’re feeling down or distressed for any length of time, odds are that your relation- ships with those around you will take a hit. Although you may think that your depression or anxiety affects only you, it impacts your friends, family, lovers, co-workers, and acquaintances. Take the quiz in Worksheet 1-4 to see if your emotions are causing trouble with your rela- tionships. Chapter 1: Sorting Out Signs of Anxiety and Depression 13 Worksheet 1-4 The Conflicted Connections Quiz ❏ 1. You guessed it; there’s no cutoff score here to tell you definitively whether or not you’re anxious or depressed. But the more items you check off, the more your relationships are suffering from your anxiety, depression, or both. Odd-numbered items usually indicate prob- lems with depression, and even-numbered items particularly accompany anxious feelings. You may feel somewhat anxious meeting new people and may be uncomfortable in the spotlight — these feelings aren’t necessarily any- thing to be concerned about. However, such issues become problematic when you find yourself avoiding social activities or meeting new people because of your shyness. Plotting Your Personal Problems Profile The Personal Problems Profile provides you with an overview of your problematic symp- toms. One good thing about this profile is that you can track how these symptoms change as you progress through the rest of this book. Tyler, a middle-aged engineer, doesn’t consider himself depressed or plagued with any emotional problems. But when he sees his primary care doctor, Tyler complains of fatigue, recent weight gain, and a noticeable loss in his sex drive. Filling out his Personal Problems Profile helps Tyler see that he has a depression that he wasn’t even consciously aware of. It’s also making me withdraw from my girlfriend, which I can see from my loss of sex drive and lack of desire to be with her. Of course, you can skip a few exercises, but the more you do, the sooner you’ll start feeling better. Writing helps you remember, clarifies your thinking, and increases focus and reflection. Look back at the quizzes earlier in this chapter and underline the most problematic thoughts, feelings, behaviors, and relationship issues for you. Then choose up to ten of the most significant items that you’ve underlined and write them in the My Personal Problems Profile space that’s provided. Chapter 1: Sorting Out Signs of Anxiety and Depression 15 In addition, put an A by the symptoms that are most indicative of anxiety (even-numbered items in the preceding quizzes) and a D by symptoms that are most consistent with depres- sion (odd-numbered items). And do they seem to mostly affect your thoughts, feelings, behaviors, or relationships? Worksheet 1-8 My Reflections Choosing Your Challenge The next four parts of this workbook cover the areas of thoughts, feelings, behaviors, and relationships. One obvious way of deciding which area to begin in is to choose the one that causes you the most problems. Wherever you choose to start, you should know that all these areas interact with each other. For example, if you have anxious thoughts about being judged, you’re likely to avoid (behavior) the spot- light. Furthermore, you may be overly sensitive to criticism from others (relationships). Part I: Analyzing Angst and Preparing a Plan 16 Nevertheless, we find that many people like to start out by tackling the problem area that best fits their personal styles. In other words, some folks are doers and others are thinkers; still others are feelers, and some are relaters. Use the Personal Style Questionnaire in Worksheet 1-9 to pinpoint and understand your preferred style. Many people find they can overcome minor to moderate emotional problems by working with books like this one. Nevertheless, some difficulties require professional help, perhaps because your anxiety or depression is especially serious or because your problems are simply too complex to be addressed by self-help methods. Work through The Serious Symptom Checklist in Worksheet 1-10 to find out if you should seriously consider seeking treatment from a mental health professional.

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Fluid moves into and out of the cells and the extracellular spaces by osmotic pressure order zestril 5mg otc blood pressure medication used in pregnancy. This is the pressure exerted by the flow of water through a semipermeable membrane separating two solutions with different concentrations of solute proven 2.5 mg zestril arteria hepatica. Osmotic pres- sure is determined by the concentration of the electrolytes and other solutes in water and is expressed as osmolarity or osmolality zestril 5 mg without a prescription hypertension bp. Serum osmolality is a better indicator of the concentration of solutes in body fluids than tonicity; tonicity is primarily used as a measure- ment of the concentration of intravenous solutions order cheap zestril prehypertension 120 80. This is a fluid that has a higher concentration of particles of solute than water. The concentration of solutes is important when determining the proper replacement fluid for a patient whose fluids and electrolytes are imbalanced. Dextran 40 tends to interfere with platelet func- tion resulting in prolonged bleeding times. It is helpful for patients who are old and malnourished and for those with hypopro- teinemia resulting from other causes. Plasmanate is non-antigenic and must not be given to patients who have anemia, increased blood volume, or congestive heart failure. Blood and Blood Products Blood and blood products consist of whole blood, packed red blood cells, plasma, and albumin. Whole blood should be used to treat severe cases of anemia—not mild cases of anemia—because one unit of whole blood elevates hemoglobin by 0. Fluid Replacement The amount of water a patient requires each day depends on the patient’s age and the nature of the patient’s medical condition. Each day the patient losses: • 400 mL to 500 mL of water through evaporation from the skin. This means that each day the patient must take in between 1900 mL and 2400 mL of fluid in order to maintain fluid-electrolyte balance. However, dis- ease and the treatment of disease can increase the patient’s output of water requiring that the patient increase the intake of water. For example, a patient who has a fever loses as much as 15% more water than the normal daily water loss. That is, the patient loses between 2185 mL and 2760 mL of water each day when he or she has a fever. Potential nursing diagnoses for a patient that is receiving fluid volume replacement therapy are: • Risk for fluid volume excess. This can occur when the patient is given too much replacement fluid, fluid is infused too rapidly, or the volume is too much for the patient’s physical size or condition. The patient should be taught: • To recognize signs and symptoms of fluid volume excess and fluid volume deficit. Potassium Potassium is an electrolyte cation that is more prevalent inside cells than it is in extracellular fluid. It is used to transmit and conduct neurological impulses and to maintain cardiac rhythms. In order for a muscle to contract, the concentration of potassium inside the cell moves out and is replaced by sodium, which is the prevalent electrolyte out- side the cell (see Sodium). The concentration of potassium and sodium is maintained by the sodium-potassium pump found in cell membranes. Patients receive potassium from their diet and excrete potassium in urine (90%) and feces (8%). Serum potassium is measured to determine if the patient has a normal range of potassium. When this happens, the patient will exhibit specific signs and symptoms and the serum potassium will be outside the normal range. Hyperkalemia Hyperkalemia occurs when a patient has a serum potassium level greater than 5. A number of factors can cause this condition including: • Impaired renal excretion (most common). The nurse must respond quickly once signs and symptoms of hyperkalemia develop as the patient is at risk for seizures, injury related to muscle weakness, and cardiac arrhythmias. Hypokalemia Hypokalemia occurs when a patient has a serum potassium level of less than 3. The patient may have the following signs and symptoms when experienc- ing hypokalemia: • Leg cramps. The nurse must respond with the following interventions as the patient is a risk for injury related to muscle weakness and cardiac arrhythmias. Take with at least a half a glass of fluid (juice or water) because potassium is extremely irritating to the gastric and intestinal mucosa. The infusion should not exceed 10 to 20 mEq per hour or the patient may experience hyperkalemia and can experience cardiac arrest. Potassium Supplements Description 10% potassium chloride 20 mEq/15 mL oral 20% potassium chloride 40 mEq/16 mL oral 10% Kaochlor Oral Potassium triplex (potassium Oral, rarely used actetate, bicarbonate, citrate) Kaon (potassium gluconate) Enteric-coated tablet. Maintenance: 20 mEq in 1–2 divided dose Kaon-Cl (potassium chloride) Enteric-coated tablet. Maintenance: 20 mEq in 1–2 divided dose Slow-K (potassium chloride) Enteric-coated tablet. Maintenance: 8 mEq Kaochlor (potassium chloride) Correction: 40–80 mEq in 3–4 divided doses K-Lyte (potassium bicarbonate) Effervescent tablet. Correction: 40–80 mEq in 3–4 divided doses K-Lyte/Cl (potassium chloride) Effervescent tablet. Correction: 40–80 mEq in 3–4 divided doses K-Dur (potassium chloride) Effervescent tablet. Correction: 40–80 mEq in 3–4 divided doses Micro-K (potassium chloride) Effervescent tablet. Don’t give potassium if the patient suffers from renal insufficiency, renal failure, or Addison’s disease. Do not give potassium if the patient has hyper- kalemia, severe dehydration, acidosis, or takes potassium-sparing diuretics. Sodium Sodium is the major cation in extracellular fluid found in tissue spaces and ves- sels. Sodium plays an important role in the regeneration and transmission of nerve impulses and affects water distribution inside and outside cells. When it shifts into the cell, depolarization (contraction) occurs; when it shifts out of the cell, potas- sium goes back into the cell and repolarization (relaxation) occurs. The kidneys regulate the sodium balance by retaining urine when the sodium concentration is low and excreting urine when the sodium concentration is high. Most excess sodium is excreted in urine although sodium also leaves the patient as perspira- tion and in feces. The serum sodium level, which is the ratio of sodium to water, is the indicator of the sodium level in a patient’s body.

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Instead the T-cell re- ceptor can only recognize its specific epitope once the antigen has been cleaved into shorter peptide fragments by the presenting cell zestril 10mg mastercard arteria bulbi vestibuli. The T-Cell System 59 immunological rejection of cell transfusions or tissue and organ transplants discount zestril on line blood pressure medication help lose weight. Its true function as a peptide-presenting molecule was not discovered until the seventies buy zestril 5 mg low price arrhythmia low blood pressure, when its role became apparent whilst testing the specificity of virus-specific cytotoxic Tcells order zestril 2.5 mg without a prescription blood pressure medication coreg. These molecules consist of a heavy a chain with three Ig-like polymorphic domains (these are encoded by 100–1000 alleles, with the a1 and a2 domains being much more polymorphic than the a3 do- main) and a nonmembrane-bound (soluble) single-domain b2 microglobulin (b2M, which is encoded by a relatively small number of alleles). Additional, non- classical, class I antigens which exhibit a low degree of polymorphism are also present on lymphohematopoietic cells and play a role in cellular differ- entiation. These are made up by two different polymorphic transmembrane chains that consist of two domains each (a1 is highly poly- morphic, whilst b1 is moderately polymorphic, and b2 is fairly constant). Usage subject to terms and conditions of license The T-Cell System 61 Presentation of Endogenous and Exogenous Antigens 2 Fig. Antigens taken up from exogenous sources (right) are cleaved into peptides within phagosomes. Usage subject to terms and conditions of license 62 2 Basic Principles of Immunology length. The complex mechanisms involved in this process have not yet been fully delineated. The term “trans- plantation antigens” is therefore a misnomer, and is only used because their real function was not discovered until a later time. T-Cell Maturation: Positive and Negative Selection Maturation of Tcells occurs largely within the thymus. The random processes governing the genetic generation of an array of T-cell receptors results ab or cd receptor chain combinations which are in the majority of cases are non-functional. However, recent experiments have shown that this is 2 probable an experimental artefact and that it is not (or not solely) the thymic epithelial cells that determine the selection process, but that this process is driven by cells formed in the bone marrow. Thus, only Tcells with moderate binding affinities are allowed to mature and exit the thymus. The enormous proliferation of immature thymocytes is paralleled by continuous cell death of large numbers of thymocytes (apop- tosis, see summary in Fig. In general, the maturation and survival of lymphocytes is considered to be dependent on a continuous, repetitive, signaling via transmembrane molecules, and cessation of these signals is usually taken as a reliable indicator of cell death. They are also called T helper cells due to their important role in T-B cell col- laboration (Fig. Although these cells sometimes demonstrate an ability to cause cytotoxic destruction in vitro, this does not hold true in vivo. These cells are also known as cytotoxic T cells due to their ability to destroy histocompatible virus-infected, or otherwise altered, target cells as well as allogeneic cells. Costimulatory molecules are not required for this lytic Kayser, Medical Microbiology © 2005 Thieme All rights reserved. They also have many other non-lytic func- tions which they execute via the production, or induction of, cytokine release. It was originally coined to distinguish these cells from the function of T helper cells, mentioned above. In most cases, this suppressive effect can in fact be explained Kayser, Medical Microbiology © 2005 Thieme All rights reserved. Thus, the name suppressor T cell suggests a regulatory function that in reality is unlikely to exist. The genetic se- quence for the c and d chains resembles that of the a and b chains, however, there are a few notable differences. The gene complex encoding the d chain is located entirely within the V and J segments of the a chain complex. There are also far fewer V segments for the c and d genes than for the a and b chains. It is possible that the increased binding variability of the d chains makes up for the small number of V segments, as a result nearly the entire variability potential of the cd receptor is concentrated within the binding region (Table 2. The amino acids coded within this region are presumed to form the center of the binding site. T cells with cd receptors recognize certain class I-like gene products in as- sociation with phospholipids and phosphoglycolipids. Although it is assumed that cd T cells may be responsible for early, low-specificity, immune defense at the skin and mu- cosa, their specificities and effector functions are still largely unknown. Immune Responses and Effector Mechanisms & The effector functions of the immune system comprise antibodies and complement-dependent mechanisms within body fluids and the mucosa, as well as tissue-bound effector mechanisms executed by T cells and mono- cytes/macrophages. Following antigen stimulation, specific B cells proliferate and differentiate into plasma cells that secrete antibodies into the surroundings. The type of B-cell re- sponse induced is determined by the amount and type of bound antigen recognized. Induction of an IgM response in response to antigens which are lipopolysaccharides—or which exhibit an highly organized, crystal-like Kayser, Medical Microbiology © 2005 Thieme All rights reserved. Immune Responses and Effector Mechanisms 67 structure containing identical and repetitively arranged determinants—is a highly efficient and T cell-independent process which involves direct cross-linking of the B-cell receptor. In contrast to this process, antibody re- sponses against monomeric or oligomeric antigens are less efficient and strictly require T cell help, for both non-self and self antigens. Other T-cell effector mechanisms are mediated in a more precise manner through cell-to-cell contacts. Examples of this in- clude perforin-dependent cytolysis and induction of the signaling pathways involved in B-cell differentiation or Ig class switching. Accordingly, once rearrangement of the Ig genes has taken place, the corresponding protein will be expressed as a surface receptor. The body faces a large number of different antigens in its lifetime, necessitating that a correspondingly large number of different receptor specificities, and therefore different B cells, must continuously be produced. When a given antigen enters an organism, it binds to the B cell which exhibits the correct receptor specificity for that antigen. One way to describe this process is to say that the antigen selects the corresponding B-cell type to which it most effi- ciently binds. However, as long as the responding B cells do not proliferate, the specificity of the response is restricted to a very small number of cells. For an effective response, clonal proliferation of the responsive B cells must be induced. After several cell divisions B cells differentiate into plasma cells which release the specific receptors into the surroundings in the form of soluble antibodies. B-cell stimulation proceeds with, or without, T cell help depending on the structure and amount of bound antigen.

Halogens can stabilize the transition states leading to reaction at the ortho and para positions discount zestril 5 mg visa prehypertension - time to act. On the other hand buy cheap zestril online heart attack 5 hour energy, the electron-withdrawing inductive effect of halogens influences the reactivity of halobenzenes buy discount zestril 2.5mg blood pressure chart generator. Cl order zestril 5mg with mastercard blood pressure medication given during pregnancy, donates an unshared pair of electrons, which give rise to relatively stable resonance structures contributing to the hybrids for the ortho- and para- substituted arenium ions. The resonance contributors formed from ortho, meta and para attacks on the chlorobenzene are shown below. Toluene, like benzene, undergoes electrophilic substitutions, where the substitutions take place in ortho and para positions. For example, the nitration of toluene produces ortho-nitro- toluene (61%) and para-nitrotoluene (39%). Oxidation of toluene Regardless of the length of the alkyl substituent in any alkylbenzene, it can be oxidized to a carboxylic acid provided that it has a hydrogen atom, bonded to the benzylic carbon. Hydroxybenzene, the simplest member of the phenols, is generally referred to as phenol. Numbering is often used to denote the position(s) of the substituent(s) on a phenol skeleton, e. Phenol itself is somewhat soluble in water (9 g per 100 g of water) because of hydrogen bonding with water. Physical properties of nitrophenols Physical properties of o-, m- and p- nitrophenols differ considerably. Intermolecular hydrogen bonding Intermolecular hydrogen bonding in ortho-nitrophenol in meta-nitrophenol 4. This intramolecular hydrogen bonding takes the place of intermolecular hydro- gen bonding with other phenol molecules or water molecules. Although weaker than carboxylic a acids, phenols are more acidic than alcohols (K values around 10À16 to a 10À18). Hydrolysis of diazonium salts Diazonium salts react with water in the presence of mineral acids to yield phenols. For example, the bromination of phenol produces ortho-bromophenol (12%) and para-bromophenol (88%). For example, phenol reacts with benzoylchloride to yield phenylbenzoate, and bromophenol reacts with toluenethionyl chloride to produce bromophenyltoluene sulphonate. This reaction is applied in the conversion of phenol itself into ortho-hydroxybenzoic acid, known as salicylic acid. Acetylation of salicylic acid produces acetylsalicylic acid (aspirin), which is the most popular painkiller in use today. A substituted benzalchloride is initially formed, but is hydrolysed by the alkaline medium. Again, salicylaldehyde could be oxidized to salicylic acid, which could be acetylated to aspirin. H H H H :O H N H N H Intermolecular hydrogen bonding Intermolecular hydrogen bonding in aniline of aniline with water Basicity of aniline Aniline, like all other amines, is a basic compound À10 (Kb¼ 4. Arylamines are stabilized relative to alkylamines because of the five resonance structures as shown below. Resonance stabilization is lost on protonation, because only two resonance structures are possible for the arylammonium ion. The group (phenyl) attached to the carbonyl carbon in the amide (benza- mide) is found joined to nitrogen in the product (aniline). The final stage of this reaction involves the formation of a quaternary ammonium salt where four organic groups are covalently bonded to nitrogen, and the positive charge of this ion is balanced by the negative chloride (ClÀ) ion. Formation of amide Aniline reacts with acid chloride to form corre- sponding amide. For example, when aniline is treated with benzoylchloride in the presence of pyridine, it produces benzanilide. For example, when aniline is treated with benzenesulphonylchloride in the presence of a base, it produces the sulphonamide N-phenylbenzenesulphonamide. Alkylamines also react with nitrous acid, but the alkanediazonium salts are so reactive that they cannot be isolated. The reaction of an arene diazonium salt with cuprous salt is known as a Sandmeyer reaction. Arenediazonium salts are extremely important in synthetic chemistry, because the diazonio group (N N) can be replaced by a nucleophile in a radical substitution reaction, e. Under proper conditions, arenediazonium salts react with certain aromatic compounds to yield products of the general formula Ar–NÀÀN–Ar ,0 called azo compounds. Sulphanilamide, the first of the sulpha drugs, acts by inhibiting the bacterial enzyme that incorporates para-aminobenzoic acid into folic acid. The lower layer (aqueous) contains the salt of aniline, and the ether layer has the neutral compound. Ether is evaporated from the ether layer using a rotary evaporator to obtain purified neutral compound. To the aqueous layer, sodium hydroxide and ether are added, and the resulting solution is shaken in a separating funnel. The ether layer (top layer) contains free aniline, and the aqueous layer (bottom layer) has the salt, sodium chloride. Ether is evaporated from the ether layer using a rotary evaporator to obtain purified aniline. In addition to the usual electrophilic substitutions, naphthalene can also undergo oxidation and reduction reactions under specific conditions as outlined below. Oxidation Oxidation of naphthalene by oxygen in the presence of vanadium pentoxide (V2O5) destroys one ring and yields phthalic anhydride (an important industrial process). N, O or S (hetero-atoms), in their rings are called heterocyclic compounds or heterocycles, e. N Pyridine Tetrahydrofuran Thiophene N is the hetero-atom O is the hetero-atom S is the hetero-atom Among the heterocyclic compounds, there are aromatic, e. Serotonin, a neuro- transmitter found in our body, is responsible for various bodily functions. However, there are some general rules to be followed in a heterocycle, especially in the use of suffixes to indicate the ring size, saturation or unsaturation as shown in the following table. For example, from the name, pyridine, where the suffix is -ine, one can understand that this heterocyclic compound contains nitrogen, has a six- membered ring system and is unsaturated. Ring with nitrogen Ring without nitrogen Ring size Maximum unsaturation Saturation Maximum unsaturation Saturation 3 irine iridine irene irane 4 ete etidine ete etane 5 ole olidine ole olane 6 ine – ine ane 7 epine – epine epane 8 ocine – ocine ocane 9 onine – onine onane 10 ecine – ecine ecane Monocyclic heterocycles containing three to ten members, and one or more hetero-atoms, are named systematically by using a prefix or prefixes to indicate the nature of the hetero-atoms as presented in the following table. Element Prefix Element Prefix Element Prefix O oxa P phospha Ge germa S thia As arsa Sn stanna Se selena Sb stiba Pb plumba Te tellura Bi bisma B bora N aza Si sila Hg mercura Two or more identical hetero-atoms are indicated by use of the multiplying prefixes di-, tri-ortetra-. When more than one distinct hetero-atom is present, the appropriate prefixes are cited in the name in descending order of group number in the periodic table, e. If both lie within the same group of the periodic table, then the order is determined by increasing atomic number, e.

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