Over the years, thousands of different pharmaceutical compounds have been synthesized, have saved countless lives, and have affected history by various other means. One particular pharmaceutical that has changed the way we live is the pain-relieving molecule aspirin. Also known as acetyl salicylic acid, aspirin was first produced by the German Bayer dying company, and begins its formation as salicyl alcohol (a phenol derivative), which is produced from the flowers of meadowsweet, or Spiraea ulmaria. The alcohol is then oxidized to become salicylic acid, whose hydrogen atom on its hydroxide group is replaced with an acetyl group (CH3CO), to form its final product, aspirin. During World War I, Bayer bought large amounts of phenol so that they could manufacture enough aspirin, which took away from the phenol supply of other natons. This meant that the phenol-based explosive compound of picric acid would be harder to produce, which hastened the the development of TNT-based explosives in these countries. After over a century since it was first marketed by Bayer in 1899, aspirin has become the most widely used of all drugs for treating illness and injury, with over forty million pounds of aspirin being produced annually in the U.S. alone.
Two other pharmaceuticals, sulfa drugs and penicillans, both antibiotics, have also shaped human history as they have saved millions of lives in fighting off various diseases. Sulfa drugs, or sulfanilamides, can be administered as the dye protosil red, which will then break down in the body to form this useful antibiotic. There are several derivatives to the sulfanilamide molecule that serve various purposes: sulfapyridine is used to fight pneumonia, sulfathiazole for gastrointestinal infections, and sulfacetamide for urinary tract infections. Penicillans, such as penicillin G, penicillin O, ampicillin, amoxicillin, and cloxacillin, also have widespread imlications in the field of medicine. This family of pharmaceuticals is effective in fighting against bacteria such as those that cause meningitis, gonorrhea, and streptococcal infections such as strep throat. With the countless lives these pharmaceuticals have saved, which can be seen from the life expectancy increase by over thirty years since the beginning of the early modern era, these molecules have the right to be called wonder drugs.
Sunday, April 22, 2012
Dyes
The use of dyes dates back thousands of years, and still continues to this day, perhaps more than ever. Though they may seem insignificant in shaping human histroy, they have in fact caused indirect developments in other fields. For example, the dye indigo, from the Indigofera tinctoria plant, was first synthetically produced and marketed by the German chemical company Badische Anilin und Soda Fabrik (BASF). This gave it the financial capital and chemical knowledge to expand into a variety of other fields and become one of the five largest chemical companies in the world. The indigo molecule is blue, but is the product of two colorless oxidized indican molecules. Most dyes follow this pattern, being altered from their colorless parent molecule to form colored compounds, such as alizarin (Turkey red) and its parent molecule anthraquinone. The French army incorporated both indigo and alizarin into their military uniforms, as well as the uniforms they supplied to the United States during the American Revolution.
Another example is the colorless naphthoquinone which produces its derivatives of juglone (brown) found in walnuts, and lawsone (red-orange) found in Indian henna. Naphthoquinone is also the parent molecule of echinochrome, carminic acid, and kermesic acid. Echinochrome is a red pigment found in sand dollars and sea urchins. Carminic acid, which makes up the scarlet cochineal dye once used by the Aztecs, contains numerous hydroxide groups, which is attributed to a brighter color. The British army adopted cochineal-dyed uniforms in the 1700s, and became known thereafter as redcoats. Kermesic acid was similar to carminic acid but was found in Egypt and never went into widespread use.
The primary yellow dye in use since ancient times and up until recently was saffron, from the Crocus sativus plant. Similar to beta-carotene, found in carrots, saffron is a long carbon chain with alternating double bonds. Another yellow dye used was picric acid (trinitrophenol), but was also highly explosive and was later used by the British in the early stages of the first World War. Synthetic dyes, such as mauve which produced a brilliant lavender purple, soon replaced naural dyes, and promoted the growth of numerous chemical companies, especially those in Germany. Though the affect of dyes on human history may not be so obvious as the affect other compounds had, they certainly made their mark, one way or another.
Another example is the colorless naphthoquinone which produces its derivatives of juglone (brown) found in walnuts, and lawsone (red-orange) found in Indian henna. Naphthoquinone is also the parent molecule of echinochrome, carminic acid, and kermesic acid. Echinochrome is a red pigment found in sand dollars and sea urchins. Carminic acid, which makes up the scarlet cochineal dye once used by the Aztecs, contains numerous hydroxide groups, which is attributed to a brighter color. The British army adopted cochineal-dyed uniforms in the 1700s, and became known thereafter as redcoats. Kermesic acid was similar to carminic acid but was found in Egypt and never went into widespread use.
The primary yellow dye in use since ancient times and up until recently was saffron, from the Crocus sativus plant. Similar to beta-carotene, found in carrots, saffron is a long carbon chain with alternating double bonds. Another yellow dye used was picric acid (trinitrophenol), but was also highly explosive and was later used by the British in the early stages of the first World War. Synthetic dyes, such as mauve which produced a brilliant lavender purple, soon replaced naural dyes, and promoted the growth of numerous chemical companies, especially those in Germany. Though the affect of dyes on human history may not be so obvious as the affect other compounds had, they certainly made their mark, one way or another.
Isoprene
Rubber, the simplest natural polymer known to man, has shaped and still shapes the world we live in today, in both positive and negative ways. Rubber components for machines, such as belts, gaskets, joints, valves, o-rings, washers, tires, and seals have allowed for major developments in transportation and the indusrial world. Mechanization of agriculture has allowed the growth of cities and has changed our society from a rural to an urban one. Though rubber has fueled the mechanization of the world, its negative effects can still be seen. In tropical rainforests such as the Amazon and the Congo, where rubber can be tapped from natural sources, members of the wealthy class (mostly whites) had once exerted power over members of the lower class, forcing them to extract rubber from these sources, in a system of indebted bondage close to that of slavery. Once rubber could be produced synthetically, however, these rubber barons went out of business, but the effects of the shameful treatment of the indigenous populations of these regions still lasts in the the form of ethnic and political strife.
Natural rubber is a polymer of the molecule isoprene, which has the following chemical structure:
When polymerized, the double bonds become single and the bond between the two center carbons becomes double. The CH2 group of one molecule bonds with the CH2 group of another. If the two CH2 groups of the isoprene molecules are on the same side of the carbon double bond, it is a cis polymer. If they are on opposite sides of the carbon double bond, as in the illustration above, it will produce a trans polymer. The cis arrangement is what natural rubber is made out of, giving it its elastic properties, where the trans arrangement causes less elasticity, and can be found in products such as golf balls. Both of these molecules have shaped history, however, in both developmental and detrimental ways, and will continue to do so, as it will also likely shape our exploration of the future, as it is an essential component of space stations, space suits, rockets, and shuttles.
Natural rubber is a polymer of the molecule isoprene, which has the following chemical structure:
When polymerized, the double bonds become single and the bond between the two center carbons becomes double. The CH2 group of one molecule bonds with the CH2 group of another. If the two CH2 groups of the isoprene molecules are on the same side of the carbon double bond, it is a cis polymer. If they are on opposite sides of the carbon double bond, as in the illustration above, it will produce a trans polymer. The cis arrangement is what natural rubber is made out of, giving it its elastic properties, where the trans arrangement causes less elasticity, and can be found in products such as golf balls. Both of these molecules have shaped history, however, in both developmental and detrimental ways, and will continue to do so, as it will also likely shape our exploration of the future, as it is an essential component of space stations, space suits, rockets, and shuttles.
Phenol
The phenol molecule, a simple aromatic molecule consisting of a benzene ring and an attached hydroxide (OH) group, has had a profound impact on society since its discovery in the mid-1800s by physician Joseph Lister. Lister, who was in the practice of surgery, wanted to improve the conditions at hospitals where death rates from the so-called hospital disease were appalling. We know today that it is actually a group of diseases with a variety of causes that is passed between patients and doctors due to unsanitary conditions, but at this point in history the theory of the presence of germs was newly found and was rejected by many. Lister, however, did believe in the existence of germs and the affect they had, so he developed a procedure to carefully clean the operating room and the patient before, during, and after surgery, which resulted in infection-free operations that soon convinced other surgeons to follow by his example. Carbolic acid, derived from coal tar, was the solution used in this sanitation process, and the phenol molecule is its main constituent.
The word phenol not only refers to the phenol molecule, but also to the phenol family to which it belongs. The antiseptic agents trichlorophenol and hexylresorcinol, and the dye trinitrophenol belong to this family, being derivatives of the phenol molecule. Also members of this family are the aromatic molecules of capsaicin, zingerone, vanillin, eugenol, and isoeugenol. More complex molecules, such as marijuana's active ingredient tetrahydrocannabinol (THC), the toxic compound gossypol, and epigallocatechin-3-gallate (found in green tea), are also members of the phenol family.
Despite its many derivatives, the parent phenol molecule has brought about the greatest changes in our world. In 1907, Belgian American Leo Baekeland, while working for the Eastman Kodak Company, produced a liquid that rapidly hardened into an amber-colored solid that conformed into whatever shape the mold it was poured into was. The new substance, which he called Bakelite, was a polymer of phenol molecules linked by CH2 cross-links, and had seemingly endless favorable properties. Among its many beneficial properties were its rigidity, heat resistance, and that it did not react easily. Now known as plastic, Bakelite had far more success than other synthetic materials intended to perform the same role, such as celluloid and shellac, which were often flammable or melted easily. Plastic soon replaced ivory, which had endangered elephant populations, in a variety of items from buttons to billiard balls. The phenol molecule, members of the phenol family, and its derivatives have no doubt had a lasting impact on human society, having permitted antiseptic surgery and having begun an Age of Plastics.
The word phenol not only refers to the phenol molecule, but also to the phenol family to which it belongs. The antiseptic agents trichlorophenol and hexylresorcinol, and the dye trinitrophenol belong to this family, being derivatives of the phenol molecule. Also members of this family are the aromatic molecules of capsaicin, zingerone, vanillin, eugenol, and isoeugenol. More complex molecules, such as marijuana's active ingredient tetrahydrocannabinol (THC), the toxic compound gossypol, and epigallocatechin-3-gallate (found in green tea), are also members of the phenol family.
Despite its many derivatives, the parent phenol molecule has brought about the greatest changes in our world. In 1907, Belgian American Leo Baekeland, while working for the Eastman Kodak Company, produced a liquid that rapidly hardened into an amber-colored solid that conformed into whatever shape the mold it was poured into was. The new substance, which he called Bakelite, was a polymer of phenol molecules linked by CH2 cross-links, and had seemingly endless favorable properties. Among its many beneficial properties were its rigidity, heat resistance, and that it did not react easily. Now known as plastic, Bakelite had far more success than other synthetic materials intended to perform the same role, such as celluloid and shellac, which were often flammable or melted easily. Plastic soon replaced ivory, which had endangered elephant populations, in a variety of items from buttons to billiard balls. The phenol molecule, members of the phenol family, and its derivatives have no doubt had a lasting impact on human society, having permitted antiseptic surgery and having begun an Age of Plastics.
Tuesday, April 17, 2012
Silk and Nylon
Silk has always been a luxury fabric prized by the wealthy of society; its many properties such as its warmth in cool weather and coolness in warm weather, its caressing feel, its wonderful luster, and its capabilty to be easily dyed, have made it so. First produced in China circa 2500 BC, silk is obtained by boiling the cocoons of silkworms and then unwinding the silk thread onto reels. Until around the sixth century AD, the Chinese had a monopoly over silk production, who then sold their products to foreign traders who brought it to various locations around the world via the Silk Road, which stretched from China to eastern Europe. Once the secrets of silk cultivation, also known as sericulture, became known about three thousand years later, European nations, especially those in Itlay, became major producers. In the New World however, sericulture was not as successful, but important developments that mechanized the spinning and weaving process were made here, mostly in the United States.
But what is it that makes silk such a desirable fabric? Silk, being a protein, is a polymer made of a variety of amino acids. Every amino acid has the basic structure H2N-CH-COOH, with a side group attached to the center, or alpha, carbon. The side group can range from a simple hydrogen atom to a far more complex molecule, and is what gives the amino acid its own unique properties. There are 22 amino acids, so a polymer of just four amino acids has 234,256 possible combinations. The polymer chains are in a zigzag arrangement, and lie parallel with adjacent chains running in opposite directions, held together by cross attractions. This produces a pleated sheet structure, which gives it the flexibilty it needs without stretching it. These properties make silk a very versatile fabric, but also makes it difficult to replicate.
None the less, attempts to find a synthetic silk were made. Such attempts proved fruitless, as the structure of silk was far too difficult to replicate, so the search for different fabrics that could fulfill the same properties of silk began. Artificial silks based on cellulose, called rayons, had similar properties to silk, but had many weaknesses: Chardonnet silk was flammable, and viscose, though still in production today, absorbs water easily. However, in 1938, a noncellulose based substitute for silk, known as nylon, went on the market. Nylon, created by Wallace Carothers at DuPont Fibersilk Company, differs from silk in that instead of being a polymer of amino acids that each have an acid group (COOH) and an amine group (NH2), it consists of two alternating molecules. These are 1,6 diaminohexane, which has two amine groups, and apidic acid, which has two acid groups. The polymer units are bonded like they are in silk, through amide links, and is structured in much the same way. This new artificial silk was a huge success, as it had exceptional strength, durability, and lightness. During World War II, tire cords, mosquito netting, weather balloons, ropes, parachute shrouds, and other military items were made of nylon. Both silk and nylon have had a significant impact on human society, having opened worldwide trade routes and promoted various other developments that we rely on today.
But what is it that makes silk such a desirable fabric? Silk, being a protein, is a polymer made of a variety of amino acids. Every amino acid has the basic structure H2N-CH-COOH, with a side group attached to the center, or alpha, carbon. The side group can range from a simple hydrogen atom to a far more complex molecule, and is what gives the amino acid its own unique properties. There are 22 amino acids, so a polymer of just four amino acids has 234,256 possible combinations. The polymer chains are in a zigzag arrangement, and lie parallel with adjacent chains running in opposite directions, held together by cross attractions. This produces a pleated sheet structure, which gives it the flexibilty it needs without stretching it. These properties make silk a very versatile fabric, but also makes it difficult to replicate.
None the less, attempts to find a synthetic silk were made. Such attempts proved fruitless, as the structure of silk was far too difficult to replicate, so the search for different fabrics that could fulfill the same properties of silk began. Artificial silks based on cellulose, called rayons, had similar properties to silk, but had many weaknesses: Chardonnet silk was flammable, and viscose, though still in production today, absorbs water easily. However, in 1938, a noncellulose based substitute for silk, known as nylon, went on the market. Nylon, created by Wallace Carothers at DuPont Fibersilk Company, differs from silk in that instead of being a polymer of amino acids that each have an acid group (COOH) and an amine group (NH2), it consists of two alternating molecules. These are 1,6 diaminohexane, which has two amine groups, and apidic acid, which has two acid groups. The polymer units are bonded like they are in silk, through amide links, and is structured in much the same way. This new artificial silk was a huge success, as it had exceptional strength, durability, and lightness. During World War II, tire cords, mosquito netting, weather balloons, ropes, parachute shrouds, and other military items were made of nylon. Both silk and nylon have had a significant impact on human society, having opened worldwide trade routes and promoted various other developments that we rely on today.
Saturday, April 14, 2012
Nitro Compounds
Besides cellulose derivatives, there are many other explosive molecules that have been discovered, most of which contain a nitro group (NO2). Known as nitro compounds, these substances have been in use for millenia and can range considerably in their explosive power, depending on how many nitro groups are in the compound. The first explosive mixture ever invented was gunpowder, also known as black powder, and was used in Ancient China, Arabia, and India. Gunpowder works by igniting a certain proportion of potassium nitrate (also known as saltpeter), sulfur, and carbon (in the form of wood charcoal), which react to produce hot, rapidly expanding gases. These gases expand so violently that a deadly shock wave is often produced, that can also propel a projectile such as a bullet or a cannonball, which is where its application in warfare becomes apparent. The first firearm, the firelock, was developed in the early 1300s and was essentially an iron tube loaded with gunpowder that was ignited by the insertion of a heated wire.
The nitrogen gas that is formed in these reactions provides the main driving force behind the explosion, as the triple bond between the two nitrogen molecules makes it very stable. One example of a nitrocompound, nitrotoluene, has only one nitro group, so it does not produce as much nitrogen gas as dinitrotoluene or trinitrotoluene (TNT), which have two and three nitro groups respectively. Another nitro molecule called nitroglycerin is also extremely volatile, but is also very dangerous as it was often unpredictable and was too easily detonated. Though the manufacture of this compound leveled many factories and killed thousands of workers, the demand for it was high and production continued. Swedish scientist Alfred Nobel developed a method however in the mid 1800s that would allow the compound nitroglycerin to be used safely and reliably. He stabilized the substance by mixing it with about one-third weight of kieselguhr, which is the remains of tiny marine animals. These two substances combine to form a plastic mass with a putty-like consistency that was easy to control but could still be detonated.
Although Nobel had intended for his invention to be used as a deterrant from war, by the late 1800s it was being used widely as a weapon of warfare, and it was first used on a grand scale in World War I. However, the use of explosives in combat also led to further developments. Germany relied heavily on TNT during the war, which requires saltpeter, which it bought from Chile. When the British blockaded the trade route between the two nations, Germany worked to find a way to synthetically produce the saltpeter compound. By 1913, German chemists had managed to do so in a process that began with the synthetic production of ammonia. This production of ammonia also greatly helped to produce efficient fertilizers that are now crucial to sustaining world agriculture. As one can see, the effects of nitro compounds on world society are widespread, having increased our ability to wage war, to construct tunnels and canals, and has even indirectly promoted improvments in world agriculture.
The nitrogen gas that is formed in these reactions provides the main driving force behind the explosion, as the triple bond between the two nitrogen molecules makes it very stable. One example of a nitrocompound, nitrotoluene, has only one nitro group, so it does not produce as much nitrogen gas as dinitrotoluene or trinitrotoluene (TNT), which have two and three nitro groups respectively. Another nitro molecule called nitroglycerin is also extremely volatile, but is also very dangerous as it was often unpredictable and was too easily detonated. Though the manufacture of this compound leveled many factories and killed thousands of workers, the demand for it was high and production continued. Swedish scientist Alfred Nobel developed a method however in the mid 1800s that would allow the compound nitroglycerin to be used safely and reliably. He stabilized the substance by mixing it with about one-third weight of kieselguhr, which is the remains of tiny marine animals. These two substances combine to form a plastic mass with a putty-like consistency that was easy to control but could still be detonated.
Although Nobel had intended for his invention to be used as a deterrant from war, by the late 1800s it was being used widely as a weapon of warfare, and it was first used on a grand scale in World War I. However, the use of explosives in combat also led to further developments. Germany relied heavily on TNT during the war, which requires saltpeter, which it bought from Chile. When the British blockaded the trade route between the two nations, Germany worked to find a way to synthetically produce the saltpeter compound. By 1913, German chemists had managed to do so in a process that began with the synthetic production of ammonia. This production of ammonia also greatly helped to produce efficient fertilizers that are now crucial to sustaining world agriculture. As one can see, the effects of nitro compounds on world society are widespread, having increased our ability to wage war, to construct tunnels and canals, and has even indirectly promoted improvments in world agriculture.
Cellulose
Where sugar began the slave trade in the early 1500s, it was another product, cotton, that maintained it through to the late 1800s. Cotton accounted for approximately two-thirds of the total value of U.S. exports by 1860 (when there was a total of four million slaves in the U.S.), most of these exports going to Europe where the raw crop was made into manufactured goods. Among these European buyers of raw cotton, Great Britain was the most prominent, whose climate was ideal for the spinning and weaving of cotton threads. During the 1800s, England experienced rapid industrial growth that stemmed from the mass manufacturing of cotton products. The agriculture-based areas of the English Midlands were soon turned into factory towns in which workers, many of whom were children, lived under deplorable conditions that prompted humanitarian efforts across England. Profits from the manufacturing of cotton were used to further industrialize the region. Canals, railways, and new factories sprung up, and this industrial expansion in England would forever change its landscape. In time however, as the countries Britain imported cotton from became industrialized themselves, England's manufacturing of cotton products met with decline.
The polysaccarhide cellulose, which makes up 90% of the cotton plant, is simply a chain of glucose molecules bonded together through condensation. Condensation occurs when the hydroxide (OH) group of two glucose molecules interact and form an H2O molecule and leave an oxygen to bond the two glucose structures together. Cellulose is strictly a structural polysaccharide however, as the human body cannot digest it. Storage polysaccharides, such as starch (found in plants) and glycogen (found in animals), are digestible and are basically slight variations of cellulose. Other compounds similar to cellulose have very different functions. Nitrocellulose (a cellulose derivative whose glucose molecules have an NO2 group instead of an OH group) is extremely volatile and was considered as an alternative to gunpowder, but failed to replace it as a number of violent factory explosions shut down the industry. Cellulose acetate, another cellulose derivative, was found to be less flammable and is used today in many commercial enterprises such as the photography business and the movie industry. The effect of cellulose is undoubtedly substantial, having sustained slavery in the southern United States, which would eventually cause a civil war, and having sparked an Industrial Revolution that would began in England but soon riveted around the world.
The polysaccarhide cellulose, which makes up 90% of the cotton plant, is simply a chain of glucose molecules bonded together through condensation. Condensation occurs when the hydroxide (OH) group of two glucose molecules interact and form an H2O molecule and leave an oxygen to bond the two glucose structures together. Cellulose is strictly a structural polysaccharide however, as the human body cannot digest it. Storage polysaccharides, such as starch (found in plants) and glycogen (found in animals), are digestible and are basically slight variations of cellulose. Other compounds similar to cellulose have very different functions. Nitrocellulose (a cellulose derivative whose glucose molecules have an NO2 group instead of an OH group) is extremely volatile and was considered as an alternative to gunpowder, but failed to replace it as a number of violent factory explosions shut down the industry. Cellulose acetate, another cellulose derivative, was found to be less flammable and is used today in many commercial enterprises such as the photography business and the movie industry. The effect of cellulose is undoubtedly substantial, having sustained slavery in the southern United States, which would eventually cause a civil war, and having sparked an Industrial Revolution that would began in England but soon riveted around the world.
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