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Chirality Timeline
Chirality timeline presents a timeline of landmark events that unfold the developments happened in the field of Chirality (chemistry), chirality. Many molecules come in two forms that are mirror images of each other, just like our hands. This type of molecule is called chiral. In nature, one of these forms is usually more common than the other. In our cells, one of these mirror images of a molecule fits "like a glove," while the other may be harmful. In nature, molecules with chirality include hormones, DNA, antibodies, and enzymes. For example, (R)-limonene smells like oranges, while (S)-limonene smells like lemons. Both molecules have the same chemical formula, but their spatial orientations are different, which makes a big difference in their biological properties. Chiral molecules in the receptors in our noses can tell the difference between these things. Chirality affects biochemical reactions, and the way a drug works depends on what kind of enantiomer it is. Many drugs are ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chirality (chemistry)
In chemistry, a molecule or ion is called chiral () if it cannot be superposed on its mirror image by any combination of rotation (geometry), rotations, translation (geometry), translations, and some Conformational isomerism, conformational changes. This geometric property is called chirality (). The terms are derived from Ancient Greek χείρ (''cheir'') 'hand'; which is the canonical example of an object with this property. A chiral molecule or ion exists in two stereoisomers that are mirror images of each other, called enantiomers; they are often distinguished as either "right-handed" or "left-handed" by their absolute configuration or some other criterion. The two enantiomers have the same chemical properties, except when reacting with other chiral compounds. They also have the same physics, physical properties, except that they often have opposite optical activity, optical activities. A homogeneous mixture of the two enantiomers in equal parts is said to be racemic mixtu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jean-Baptiste Biot
Jean-Baptiste Biot (; ; 21 April 1774 – 3 February 1862) was a French physicist, astronomer, and mathematician who co-discovered the Biot–Savart law of magnetostatics with Félix Savart, established the reality of meteorites, made an early balloon flight, and studied the polarization of light. The biot (a CGS unit of electrical current), the mineral biotite, and Cape Biot in eastern Greenland were named in his honour. Biography Jean-Baptiste Biot was born in Paris on 21 April 1774 the son of Joseph Biot, a treasury official. He was educated at Lyceum Louis-le-Grand and École Polytechnique in 1794. Biot served in the artillery before he was appointed professor of mathematics at Beauvais in 1797. He later went on to become a professor of physics at the Collège de France around 1800, and three years later was elected as a member of the French Academy of Sciences. In July 1804, Biot joined Joseph Louis Gay-Lussac for the first scientific hot-air balloon ride to measure how ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joseph Achille Le Bel
Joseph Achille Le Bel (21 January 1847 in Pechelbronn – 6 August 1930, in Paris, France) was a French chemist. He is best known for his work in stereochemistry. Le Bel was educated at the École Polytechnique in Paris. In 1874 he announced his theory outlining the relationship between molecular structure and optical activity. This discovery laid the foundation of the science of stereochemistry, which deals with the spatial arrangement of atoms in molecules. This hypothesis was put forward in the same year by the Dutch physical chemist Jacobus Henricus van 't Hoff and is currently known as Le Bel–van't Hoff rule. Le Bel wrote ''Cosmologie Rationelle'' (Rational Cosmology) in 1929. Works * * * See also * Hexamethylbenzene *Optical rotation Optical rotation, also known as polarization rotation or circular birefringence, is the rotation of the orientation of the plane of polarization about the optical axis of linearly polarized light as it travels through certa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joseph Achille Le Bel
Joseph Achille Le Bel (21 January 1847 in Merkwiller-Pechelbronn, Pechelbronn – 6 August 1930, in Paris, France) was a French chemist. He is best known for his work in stereochemistry. Le Bel was educated at the École Polytechnique in Paris. In 1874 he announced his theory outlining the relationship between molecular structure and optical activity. This discovery laid the foundation of the science of stereochemistry, which deals with the spatial arrangement of atoms in molecules. This hypothesis was put forward in the same year by the Dutch physical chemist Jacobus Henricus van 't Hoff and is currently known as Le Bel–van't Hoff rule. Le Bel wrote ''Cosmologie Rationelle'' (Rational Cosmology) in 1929. Works * * * See also *Hexamethylbenzene *Optical rotation References Royal Society of Chemistry obituary 1847 births 1930 deaths 19th-century French chemists Members of the French Academy of Sciences Foreign Members of the Royal Society Stereochemists People from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
