Sulfanilamide and its derivatives 


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Sulfanilamide and its derivatives



The most important development in the history of chemotherapy was the discovery of the antibacterial powers of p-aminobenzene sulfonamide and its derivatives. This compound is better known as sulfonamide, which is a perfectly proper chemical name, since it is the amide of sulfanilic acid.

Synthesis. The fundamental intermediate common to all the derivatives of sulfanilamide is N-acetylsulfanilyl chloride. On treatment with excess ammonia and hydrolysis of the acetyl group with excess mineral acid or base, sulfanilamide is produced.

Sulfаnilamide is a white, odorless, crystalline compound with a slightly sweet taste, melting range 164.5° to 166.5°, soluble in water. It is readily (швидко) soluble in boiling water, hot alcohol, cold hydrochloric acid, cold dilute sodium hydroxide, and cold acetone. It is soluble in ether, chloroform, and benzene. It is assayed by solution in hydrochloric acid and diazotization with standard sodium nitrite solution, using starch-iodine to determine the end point. This same method of assay (аналіз, проба) is used for all N-substituted sulfanilamides.

Sulfanilamide is usually given in the form of tablets. In both mild and severe infections, the usual dose is calculated as 0.1 gm per kilogram of body weight per day, divided into six parts and given at intervals of 4 h, day and night until the temperature of the patient is normal for 5 days. The drug exhibits a number of toxic reactions such as dizziness, cyanosis, hemolytic anemia, psychosis, acidosis, fever, and rash. Adequate care by a physician is, therefore, essential in the use of the drug. Sodium bicarbonate is commonly given to counteract acidosis. It has been found that p-aminobenzoic acid in relatively small amounts overcomes the antibacterial action of sulfanilamide and its derivatives. The administration of local anaesthetics derived from this compound, such as procaine, monocaine, etc., therefore, must be avoided.

 

.Mach a Noun with proper Adjective:

А. heart - серце, lungs - легені, kidneys - нирки, stomach - шлунок, intestine - кишковик, brain - мозок, blood - кров, vessel- судина, gland- залоза, muscle - м` яз.

В. hepatic, cerebral, gastric, colic, haemal, vascular, nephrotic, cardiac, pulmonary, glandular, muscular

 

Answer the questions:

Model: Will he explain the properties of this compound?

No, the properties of this compound have already been explained.

1. Will you use sulfanilamide in your experiment? 2. Is it necessary to determine the melting point of the substance? 3. Will he cold hydrochloric acid in the test for sulfanilamide? 4. Will they receive an intermediate substance on treatment with excess ammonia? 5. Is it necessary to repeat the test using starch-iodine paste?

 

CARDIAC GLYCOSIDES

Cardiac glycosides include crude drugs and their preparations which possess cardiotonic properties by virtue (завдяки) of their glycosidal content. The important drugs are: Digitalis, Strophanthus, their preparations, and purified glycosides obtained from them.

Digitalis has been the subject of long investigation. The constituents which are now recognized as being of the greatest importance as cardiovascular agents are digitoxin, gitoxin, digoxin and lantoside. Digitoxin is the most active principle. Other constituents of digitalis are digitoflavin, digitophyllin, etc.

The chief therapeutic use for digitalis (наперстянка) is in the treatment of congestive heart failure. It is of value regardless of whether the failure is predominantly of the right or left side of the heart. The type of rhythm exhibited by the decompensated heart is secondary in importance, and digitalis exerts its salutary effects (здійснює цілющий вплив) on the failing heart with normal sinus rhythm as well as on the failing heart exhibiting ventricular fibrillation.

The mechanism by which digitalis and all allied (споріднені) cardiac glycosides exert beneficial effects on the failing heart is identical, namely, a direct cardiotonic action on the myocardium to increase the force of contraction and to increase cardiac tone. Slowing of the cardiac rate occurs only when the rate was originally rapid due to the failure.

The signs and symptoms of heart failure are in large measure abolished by digitalis, but bed rest, sedatives, and often diuretics and restriction (обмеження) of fluid intake may be required to obtain best results.

Two types of digitalis dosage are recognized, initial dose for digitalization, and maintenance dose for chronic therapy. Digitalization is usually complete when the patient has ingested the equivalent of a total of 1.2 gm of powdered digitalis in a period of 48 to 96 hours. This amount can be divided into several equal daily doses, and the total daily dose is usually divided into two - three equal amounts.

By maintenance dose is meant the daily dose which will give optimal digitalis effects and replace the glycoside which is constantly being destroyed or excreted. Optimal effects can be obtained without toxic effects, and the optimal dose is not necessarily the tolerated dose.

 

Task:

1. Change sentences below using Present Perfect:

1. Our scientists make great attempts in search of new cardiac drugs. 2. Investigations on the beneficial effects of cardiac glycosides are carried out. 3. Digitalis is a very effective drug in heart failures.

2. Translate into English:

1. Серцеві глікозиди є ефективним засобом для лікування гострої серцевої недостатності. 2. Серцеві глікозиди покращують скорочувальну здатність серцевого м`язу. 3. Серцеві глікозиди зменшують кількість серцевих скорочень за одиницю часу. 4. Препарати дигіталіса, завдяки вмісту глікозиду, знаходять широке використання в терапевтичній практиці.

3.Answer the questions:

1. What drugs do cardiac glycosides include? 2. What action do digitalis constituents exert on the heart? 3. What cases is digitalis administered in? 4. How does digitalis exert beneficial effects on the failing heart? 5. How many types of digitalis dosage are recognized? 6. Can optimal effects be obtained without toxic effects? 7. When is digitalization usually complete? 8. What are the chief constituents of digitalis?

 

MINERALS

Minerals are needed for the proper composition of body fluids, the formation of blood and bone, the maintenance of healthy nerve function and the regulation of muscle tone, including that of the muscles of the cardiovascular system. Like vitamins, minerals function as coenzymes, enabling the body to perform its functions, including energy production, growth, and healing. Because all enzyme activities involve minerals, the latter are essential for the proper utilization of vitamins and other nutrients.

The human body, as all of nature, must maintain its proper chemical balance. This balance depends on the levels of different minerals in the body and especially the ratios (пропорція) of certain mineral levels to one another. The level of each mineral in the body has an effect on every other, so if one is out of balance, all mineral levels are affected. If not corrected, this can start a chain reaction of imbalances that leads to illness.

Minerals are naturally occurring elements found in the earth. Rock formations are made up of mineral salts. Rock and stone are gradually broken down into tiny fragments by erosion, a process that can take literally millions of years. The resulting dust and sand accumulate, forming the basis of soil. The soil is teeming (наповнена) with microbes that utilize these tiny crystals of mineral salts, which are then passed from the soil to plants. The plants are eaten by herbivorous ( травоїдні ) animals. We obtain these minerals by consuming plants or herbivorous animals.

Nutritionally, minerals belong to two groups: macrominerals and microminerals. Macrominerals include calcium, magnesium, sodium, potassium, and phosphorus. These are needed in larger amounts than microminerals. Although only minute quantities of microminerals are needed, they are nevertheless important for good health. Microminerals include boron, chromium, copper, germanium, iodine, iron, manganese, molybdenum, selenium, silicon, sulfur, vanadium, and zinc.

Minerals are often found in multivitamin formulas. Minerals can also be sold as single supplements. These are available in tablet, capsule, powder, and liquid forms. Some are available in chelated (хелатна) form, which means that the minerals are bounded to protein molecules that transport them to the bloodstream and enhance their absorption. When mineral supplements are taken with a meal, they are usually automatically chelated in the stomach during digestion.

1. Create nouns from the given verbs using suffix -(a)tion:

to composite – створювати → composition – створення

to form, to regulate, to product, to react, to digest, to prepare.



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