Adolf Otto Reinhold Windaus
   HOME

TheInfoList



OR:

Adolf Otto Reinhold Windaus (; 25 December 1876 – 9 June 1959) was a German
chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe th ...
who won a
Nobel Prize in Chemistry ) , image = Nobel Prize.png , alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then "M ...
in 1928 for his work on
sterol Sterol is an organic compound with formula , whose molecule is derived from that of gonane by replacement of a hydrogen atom in position 3 by a hydroxyl group. It is therefore an alcohol of gonane. More generally, any compounds that contain the go ...
s and their relation to
vitamin A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an essential micronutrient that an organism needs in small quantities for the proper functioning of its metabolism. Essential nutrie ...
s. He was the
doctoral advisor A doctoral advisor (also dissertation director, dissertation advisor; or doctoral supervisor) is a member of a university faculty whose role is to guide graduate students who are candidates for a doctorate, helping them select coursework, as w ...
of
Adolf Butenandt Adolf Friedrich Johann Butenandt (; 24 March 1903 – 18 January 1995) was a German biochemist. He was awarded the Nobel Prize in Chemistry in 1939 for his "work on sex hormones." He initially rejected the award in accordance with government po ...
who also won a Nobel Prize in Chemistry in 1939.


Biography

He was born in
Berlin, Germany Berlin ( , ) is the capital and List of cities in Germany by population, largest city of Germany by both area and population. Its 3.7 million inhabitants make it the European Union's List of cities in the European Union by population within ci ...
on 25 December 1876 to a family who owned a drapery business. He attended a prestigious French grammar school, where he focused primarily on literature. Windaus began studying medicine at the
University of Berlin Humboldt-Universität zu Berlin (german: Humboldt-Universität zu Berlin, abbreviated HU Berlin) is a German public research university in the central borough of Mitte in Berlin. It was established by Frederick William III on the initiative ...
in about 1895 then proceeded to study chemistry at the
University of Freiburg The University of Freiburg (colloquially german: Uni Freiburg), officially the Albert Ludwig University of Freiburg (german: Albert-Ludwigs-Universität Freiburg), is a public research university located in Freiburg im Breisgau, Baden-Württemb ...
. He married Elizabeth Resau in 1915 and they had three children together, Günter, Gustav, and Margarete. After earning his PhD in medicine, Windaus became the head of the chemical institute at the
University of Göttingen The University of Göttingen, officially the Georg August University of Göttingen, (german: Georg-August-Universität Göttingen, known informally as Georgia Augusta) is a public research university in the city of Göttingen, Germany. Founded ...
from 1915 to 1944. Throughout his life, Windaus won many awards including the
Goethe Medal The Goethe Medal, also known as the Goethe-Medaille, is a yearly prize given by the Goethe-Institut honoring non-Germans "who have performed outstanding service for the German language and for international cultural relations". It is an offici ...
, the Pasteur Medal, and the Nobel Prize for Chemistry. In addition to his many accomplishments and discoveries in science, Windaus was also one of the very few German chemists who did not work with the Nazis and openly opposed their regime. As the head of the chemical institute at the
University of Göttingen The University of Göttingen, officially the Georg August University of Göttingen, (german: Georg-August-Universität Göttingen, known informally as Georgia Augusta) is a public research university in the city of Göttingen, Germany. Founded ...
, Windaus personally defended one of his Jewish graduate students from dismissal. Windaus believed that while every man had a moral code, his science was motivated by curiosity, and was not driven by politics, ethics, and applications of his discoveries. This viewpoint caused Windaus to decline to research poison gas during
World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was List of wars and anthropogenic disasters by death toll, one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, ...
.


Research

He was involved in the discovery of the transformation of
cholesterol Cholesterol is any of a class of certain organic molecules called lipids. It is a sterol (or modified steroid), a type of lipid. Cholesterol is biosynthesized by all animal cells and is an essential structural component of animal cell memb ...
through several steps to vitamin D3 (Cholecalciferol). He gave his patents to Merck and
Bayer Bayer AG (, commonly pronounced ; ) is a German multinational pharmaceutical and biotechnology company and one of the largest pharmaceutical companies in the world. Headquartered in Leverkusen, Bayer's areas of business include pharmaceutic ...
and they brought out the medical Vigantol in 1927. Sterols Windaus began his research by studying sterols. In particular, Windaus studied
cholesterol Cholesterol is any of a class of certain organic molecules called lipids. It is a sterol (or modified steroid), a type of lipid. Cholesterol is biosynthesized by all animal cells and is an essential structural component of animal cell memb ...
, which is the best known sterol. Sterols are nitrogen-free secondary alcohols with high molecular weight that contain alicylic systems, or hydrocarbon rings. Cholesterol was first discovered in human
gallstone A gallstone is a stone formed within the gallbladder from precipitated bile components. The term cholelithiasis may refer to the presence of gallstones or to any disease caused by gallstones, and choledocholithiasis refers to the presence of mi ...
s and is a mono-unsaturated alcohol found in all higher animals, both as a free alcohol and
fatty acid ester Fatty acid esters (FAEs) are a type of ester that result from the combination of a fatty acid with an alcohol. When the alcohol component is glycerol, the fatty acid esters produced can be monoglycerides, diglycerides, or triglycerides. Dietary ...
. Windaus was fascinated by how cholesterol levels in the body fluctuate, in particular how it increases during pregnancy and decreases during disease. He researched sterols in
insect Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pa ...
s,
echinoderm An echinoderm () is any member of the phylum Echinodermata (). The adults are recognisable by their (usually five-point) radial symmetry, and include starfish, brittle stars, sea urchins, sand dollars, and sea cucumbers, as well as the ...
ata, and
sponge Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate throu ...
s, called zoosterols. Many of these zoosterols have the same formula as cholesterol, except for spongosterol, which is a saturated sterol and more different from cholesterol than the other zoosterols. In plants, the sterols are known as
phytosterol Phytosterols are phytosteroids, similar to cholesterol, that serve as structural components of biological membranes of plants. They encompass plant sterols and stanols. More than 250 sterols and related compounds have been identified. Free phyt ...
s. Windaus found that the most common phytosterols are sitosterols, which have the same formula as cholesterol. There are also saturated phytosterols that are mixed in with these unsaturated sitosterols in small quantities. There are also alcohol-like phytosterols, which contain one more
hydroxyl group In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy ...
than sitosterols and a different number of carbons. Mycosterols are sterols which are found in
fungi A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately fr ...
.
Ergosterol Ergosterol (ergosta-5,7,22-trien-3β-ol) is a sterol found in cell membranes of fungi and protozoa, serving many of the same functions that cholesterol serves in animal cells. Because many fungi and protozoa cannot survive without ergosterol, t ...
is one significant mycosterol as it has three double bonds, in comparison to the one double bond in cholesterol. In his research, Windaus did not find sterols to exist in
bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were am ...
, which he found to be surprising. This research of the composition of sterols, along with their connection to vitamins, earned Windaus the Nobel Prize in Chemistry in 1928. Vitamin D2 and D3
Rickets Rickets is a condition that results in weak or soft bones in children, and is caused by either dietary deficiency or genetic causes. Symptoms include bowed legs, stunted growth, bone pain, large forehead, and trouble sleeping. Complications ma ...
, a bone disease resulting from vitamin D deficiency, was originally treated in the early 1900s through essential dietary factors such as whole milk or cod-liver oil. It was also postulated that increase sunlight was improving conditions, but was improperly concluded that
cholesterol Cholesterol is any of a class of certain organic molecules called lipids. It is a sterol (or modified steroid), a type of lipid. Cholesterol is biosynthesized by all animal cells and is an essential structural component of animal cell memb ...
was the precursor activated via UV light. In testing this, investigators under Windaus’ instruction found that completely pure cholesterol - converted into its dibromide and recrystallized - had lost its antirachitic effects upon
irradiation Irradiation is the process by which an object is exposed to radiation. The exposure can originate from various sources, including natural sources. Most frequently the term refers to ionizing radiation, and to a level of radiation that will serve ...
. It was then postulated that a different substance associated with ‘chemically pure’ cholesterol through all usual stages of purification is the precursor to
vitamin D Vitamin D is a group of Lipophilicity, fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and many other biological effects. In humans, the most important compounds in this group ar ...
. The impurity was able to precipitate with
digitonin Digitonin is a steroidal saponin (saraponin) obtained from the foxglove plant ''Digitalis purpurea''. Its aglycone is digitogenin, a spirostan steroid. It has been investigated as a detergent, as it effectively water-solubilizes lipids. As such, ...
, showing chemical properties of a
steroid A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and ...
with three double bonds. The three UV
absorption Absorption may refer to: Chemistry and biology *Absorption (biology), digestion **Absorption (small intestine) *Absorption (chemistry), diffusion of particles of gas or liquid into liquid or solid materials *Absorption (skin), a route by which s ...
peaks (see image) of the active impurity was used to purify, and become highly concentrated through high-vacuum
distillation Distillation, or classical distillation, is the process of separating the components or substances from a liquid mixture by using selective boiling and condensation, usually inside an apparatus known as a still. Dry distillation is the he ...
and charcoal adsorption techniques. In evaluating a variety of sterols that showed antirachitic activity upon irradiation, done so in consultation with A.F. Hess, O. Rosenheim, and T.A. Webster,
ergosterol Ergosterol (ergosta-5,7,22-trien-3β-ol) is a sterol found in cell membranes of fungi and protozoa, serving many of the same functions that cholesterol serves in animal cells. Because many fungi and protozoa cannot survive without ergosterol, t ...
(see image)- Ca27H42 – was found to be the only precursor of vitamin D, convertible under wavelength between 253 and 302 nm. Similarities of ergosterol to that of the active fraction from cholesterol included similar UV spectrums, rapid destruction by
oxidation Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or ...
, and production of the same color reaction with
sulfuric acid Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid ( Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen and hydrogen, with the molecular fo ...
. This production of Vitamin D2, or
calciferol Vitamin D is a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and many other biological effects. In humans, the most important compounds in this group are vitamin D3 (c ...
(see image), was a complete cure to rachitis – 100,000 times more effective than fish liver oil – and Windaus and his group were able to determine its chemical properties. This included being
isomer In chemistry, isomers are molecules or polyatomic ions with identical molecular formulae – that is, same number of atoms of each element – but distinct arrangements of atoms in space. Isomerism is existence or possibility of isomers. Is ...
ic with ergosterol with a
hydroxyl In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydrox ...
group and three conjugated double bonds; the correct structure was confirmed in 1936.The possibility of
polymerization In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. There are many f ...
was tested to be inaccurate through evaluating the molecular weight, and were also able to denounce certain
isomerization In chemistry, isomerization or isomerisation is the process in which a molecule, polyatomic ion or molecular fragment is transformed into an isomer with a different chemical structure. Enolization is an example of isomerization, as is tautomeriz ...
. The secondary alcohol displacing to a double bond via Zerewitinoff's method (see image) was shown to not occur, as well as the double bond transforming to a steric rearrangement didn't occur under observance of
titration Titration (also known as titrimetry and volumetric analysis) is a common laboratory method of quantitative chemical analysis to determine the concentration of an identified analyte (a substance to be analyzed). A reagent, termed the ''titrant'' ...
and
catalytic hydrogenation Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organic ...
. Ergosterol was originally found in fungi and not animal organisms, so the question of obtaining Vitamin D from sunlight was still in question and studied by Windaus long after receiving the Nobel Prize. In isolating and identifying 7-dehydrocholesterol in hog skin, and later human skin, whole milk, and animal liver, it too was antirachitic upon irradiation. This was already a known compound derived from cholesterol, and the new irradiation product was named Vitamin D3, or
cholecalciferol Cholecalciferol, also known as vitamin D3 and colecalciferol, is a type of vitamin D that is made by the skin when exposed to sunlight; it is found in some foods and can be taken as a dietary supplement. Cholecalciferol is made in the skin fo ...
(see image). Windaus established the structure by investigating the photochemical reactions within its formation.


References

Notes Sources * * * *


External links

* including the Nobel Lecture, 12 December 1928 ''Constitution of Sterols and Their Connection with Other Substances Occurring in Nature'' {{DEFAULTSORT:Windaus, Adolf Otto Reinhold 1876 births 1959 deaths 20th-century German chemists German Nobel laureates Nobel laureates in Chemistry Scientists from Berlin People from the Province of Brandenburg Recipients of the Pour le Mérite (civil class) University of Freiburg alumni University of Freiburg faculty Humboldt University of Berlin alumni Academics of the University of Innsbruck University of Göttingen faculty Knights Commander of the Order of Merit of the Federal Republic of Germany Französisches Gymnasium Berlin alumni