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Galantamine
Galantamine is used for the treatment of cognitive decline in mild to moderate Alzheimer's disease and various other memory impairments. It is an alkaloid that has been isolated from the bulbs and flowers of ''Galanthus nivalis'' (Common snowdrop), ''Galanthus caucasicus'' (Caucasian snowdrop), '' Galanthus woronowii'' (Voronov's snowdrop), and some other members of the family '' Amaryllidaceae'', such as ''Narcissus'' (daffodil), '' Leucojum aestivum'' (snowflake), and ''Lycoris'' including ''Lycoris radiata'' (red spider lily). It can also be produced synthetically. Studies of usage in modern medicine began in the Soviet Union in the 1950s. Galantamine was isolated for the first time from bulbs of ''Galanthus nivalis'' (common snowdrop) by the Bulgarian chemist D. Paskov and his team in 1956. The active ingredient was extracted, identified, and studied, in particular in relation to its acetylcholinesterase (AChE)-inhibiting properties. The first industrial process was devel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimitar Paskov
Dimitar Paskov (, 18 October 1914, Gorno Brodi – 24 April 1986, Bulgaria) is a Bulgarian chemist who led the Sopharma team that extracted NivalinCHRUSCIEL, M. and VARAGIĆ, V. (1966), THE EFFECT OF GALANTAMINE ON THE BLOOD PRESSURE OF THE RAT. British Journal of Pharmacology and Chemotherapy, 26: 295–301. doi: 10.1111/j.1476-5381.1966.tb01908.x (Galantamine) in 1959. The original phytopreparation is an extract of the alkaloid from bulbs of Galanthus nivalis, common snowdrop. Galantamine hydrobromide (Nivalin) has formula C17H21NO3.HBr and molecular weight 386.3. References [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galantamine Total Synthesis
The article concerns the total synthesis of galanthamine, a drug used for the treatment of mild to moderate Alzheimer's disease. The natural source of galantamine are certain species of daffodil and because these species are scarce and because the isolation of galanthamine from daffodil is expensive (a 1996 figure specifies 50,000 US dollar per kilogram, the yield from daffodil is 0.1–0.2% dry weight) alternative synthetic sources are under development by means of total synthesis. Outline In 1962 racemic galanthamine and epi-galanthamine were prepared by organic reduction of racemic narwedine by D. H. R. Barton. Narwedine is the related enone (galanthamine the allyl alcohol) obtained in an oxidative coupling. Chemical yield: 1.4%. In addition they isolated (−)-narwardine by chiral resolution from a mixture of racemix narwedine and 0.5 equivalents of (+)-galanthamine. In this way they were able to obtain (−)galanthamine again by reduction In 1976 Kametani obtained both gala ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snowdrop
''Galanthus'' (from Ancient Greek , (, "milk") + (, "flower")), or snowdrop, is a small genus of approximately 20 species of bulbous perennial herbaceous plants in the family Amaryllidaceae. The plants have two linear leaves and a single small white drooping bell-shaped flower with six petal-like (petaloid) tepals in two circles (whorls). The smaller inner petals have green markings. Snowdrops have been known since the earliest times under various names, but were named ''Galanthus'' in 1753. As the number of recognised species increased, various attempts were made to divide the species into subgroups, usually on the basis of the pattern of the emerging leaves (vernation). In the era of molecular phylogenetics this characteristic has been shown to be unreliable and now seven molecularly defined clades are recognised that correspond to the biogeographical distribution of species. New species continue to be discovered. Most species flower in winter, before the vernal equinox ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CYP2D6
Cytochrome P450 2D6 (CYP2D6) is an enzyme that in humans is encoded by the ''CYP2D6'' gene. ''CYP2D6'' is primarily expressed in the liver. It is also highly expressed in areas of the central nervous system, including the substantia nigra. CYP2D6, a member of the cytochrome P450 mixed-function oxidase system, is one of the most important enzymes involved in the metabolism of xenobiotics in the body. In particular, CYP2D6 is responsible for the metabolism and elimination of approximately 25% of clinically used drugs, via the addition or removal of certain functional groups – specifically, hydroxylation, demethylation, and dealkylation. CYP2D6 also activates some prodrugs. This enzyme also metabolizes several endogenous substances, such as hydroxytryptamines, neurosteroids, and both ''m''-tyramine and ''p''-tyramine which CYP2D6 metabolizes into dopamine in the brain and liver. Considerable variation exists in the efficiency and amount of CYP2D6 enzyme produced betwee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leucojum Aestivum
''Leucojum aestivum'', commonly called summer snowflake or Loddon lily (see ), is a plant species widely cultivated as an ornamental. It is native to most of Europe from Spain and Ireland to Ukraine, with the exception of Scandinavia, Russia, Belarus and the Baltic countries. It is also considered native to Turkey, Iran and the Caucasus. It is naturalized in Denmark, South Australia, New South Wales, Nova Scotia and much of the eastern United States. Description ''Leucojum aestivum'' is a perennial bulbous plant, generally tall, but some forms reach . Its leaves, which are well developed at the time of flowering, are strap-shaped, wide, reaching to about the same height as the flowers. The flowering stem ( scape) is hollow and has wings with translucent margins. The pendant flowers appear in late spring and are borne in umbels of usually three to five, sometimes as many as seven. The flower stalks (pedicels are of different lengths, long. The flowers are about in diameter and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daffodil
''Narcissus'' is a genus of predominantly spring flowering perennial plants of the amaryllis family, Amaryllidaceae. Various common names including daffodil,The word "daffodil" is also applied to related genera such as '' Sternbergia'', ''Ismene'' and ''Fritillaria meleagris''. It has been suggested that the word "Daffodil" be restricted to the wild species of the British Isles, '' N. pseudonarcissus''. narcissus, and jonquil are used to describe all or some members of the genus. ''Narcissus'' has conspicuous flowers with six petal-like tepals surmounted by a cup- or trumpet-shaped corona. The flowers are generally white and yellow (also orange or pink in garden varieties), with either uniform or contrasting coloured tepals and corona. ''Narcissus'' were well known in ancient civilisation, both medicinally and botanically, but formally described by Linnaeus in his ''Species Plantarum'' (1753). The genus is generally considered to have about ten sections with approximately 50 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homer
Homer (; grc, Ὅμηρος , ''Hómēros'') (born ) was a Greek poet who is credited as the author of the ''Iliad'' and the ''Odyssey'', two epic poems that are foundational works of ancient Greek literature. Homer is considered one of the most revered and influential authors in history. Homer's ''Iliad'' centers on a quarrel between King Agamemnon and the warrior Achilles during the last year of the Trojan War. The ''Odyssey'' chronicles the ten-year journey of Odysseus, king of Ithaca, back to his home after the fall of Troy. The poems are in Homeric Greek, also known as Epic Greek, a literary language which shows a mixture of features of the Ionic and Aeolic dialects from different centuries; the predominant influence is Eastern Ionic. Most researchers believe that the poems were originally transmitted orally. Homer's epic poems shaped aspects of ancient Greek culture and education, fostering ideals of heroism, glory, and honor. To Plato, Homer was simply the one who ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galanthus Nivalis
''Galanthus nivalis'', the snowdrop or common snowdrop, is the best-known and most widespread of the 20 species in its genus, ''Galanthus''. Snowdrops are among the first bulbs to bloom in spring and can form impressive carpets of white in areas where they are native or have been naturalised. They should not be confused with the snowflakes, in the genera ''Leucojum'' and '' Acis''. Naming The generic name ''Galanthus'', from the Greek ''gala'' (milk) and ''anthos'' (flower), was given to the genus by Carl Linnaeus in 1735. He described ''Galanthus nivalis'' in his ' published in 1753. The epithet means "of the snow", referring either to the snow-like flower or the plant's early flowering. The common name snowdrop first appeared in the 1633 edition of John Gerard's ''Great Herbal'' (in the first edition (1597) he described it as the "Timely flowring Bulbus violet"). The derivation of the name is uncertain, although it may have come from the German word ''Schneetropfen'', which wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetylcholinesterase
Acetylcholinesterase (HGNC symbol ACHE; EC 3.1.1.7; systematic name acetylcholine acetylhydrolase), also known as AChE, AChase or acetylhydrolase, is the primary cholinesterase in the body. It is an enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. A ... that catalysis, catalyzes the breakdown of acetylcholine and some other choline esters that function as neurotransmitters: : acetylcholine + H2O = choline + acetate It is found at mainly neuromuscular junctions and in chemical synapses of the cholinergic type, where its activity serves to terminate neurotransmission, synaptic transmission. It belongs to the carboxylesterase family of enzymes. It is the primary target of inhibition by organophosphorus compounds such as nerve agents and pesticides. Enzyme structure and mechani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oral Administration
Oral administration is a route of administration where a substance is taken through the mouth. Per os abbreviated to P.O. is sometimes used as a direction for medication to be taken orally. Many medications are taken orally because they are intended to have a systemic effect, reaching different parts of the body via the bloodstream, for example. Oral administration can be easier and less painful than other routes, such as injection. However, the onset of action is relatively low, and the effectiveness is reduced if it is not absorbed properly in the digestive system, or if it is broken down by digestive enzymes before it can reach the bloodstream. Some medications may cause gastrointestinal side effects, such as nausea or vomiting, when taken orally. Oral administration can also only be applied to conscious patients, and patients willing and able to swallow. Terminology ''Per os'' (; ''P.O.'') is an adverbial phrase meaning literally from Latin "through the mouth" or "by mouth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soviet Union
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national republics; in practice, both its government and its economy were highly centralized until its final years. It was a one-party state governed by the Communist Party of the Soviet Union, with the city of Moscow serving as its capital as well as that of its largest and most populous republic: the Russian SFSR. Other major cities included Leningrad (Russian SFSR), Kiev (Ukrainian SSR), Minsk ( Byelorussian SSR), Tashkent (Uzbek SSR), Alma-Ata (Kazakh SSR), and Novosibirsk (Russian SFSR). It was the largest country in the world, covering over and spanning eleven time zones. The country's roots lay in the October Revolution of 1917, when the Bolsheviks, under the leadership of Vladimir Lenin, overthrew the Russian Provisional Government ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hermes
Hermes (; grc-gre, Ἑρμῆς) is an Olympian deity in ancient Greek religion and mythology. Hermes is considered the herald of the gods. He is also considered the protector of human heralds, travellers, thieves, merchants, and orators. He is able to move quickly and freely between the worlds of the mortal and the divine, aided by his winged sandals. Hermes plays the role of the psychopomp or "soul guide"—a conductor of souls into the afterlife. In myth, Hermes functions as the emissary and messenger of the gods, and is often presented as the son of Zeus and Maia, the Pleiad. Hermes is regarded as "the divine trickster," about which the '' Homeric Hymn to Hermes'' offers the most well-known account. His attributes and symbols include the herma, the rooster, the tortoise, satchel or pouch, talaria (winged sandals), and winged helmet or simple petasos, as well as the palm tree, goat, the number four, several kinds of fish, and incense. However, his main symbol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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