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Methyllycaconitine
Methyllycaconitine (MLA) is a diterpenoid alkaloid found in many species of ''Delphinium'' (larkspurs). In common with many other diterpenoid alkaloids, it is toxic to animals, although the acute toxicity varies with species. Early research was focused on identifying, and characterizing the properties of methyllycaconitine as one of the principal toxins in larkspurs responsible for livestock poisoning in the mountain rangelands of North America. Methyllycaconitine has been explored as a possible therapeutic agent for the treatment of spastic paralyses in man, and it has been shown to have insecticidal properties. Most recently, it has become an important molecular probe for studying the pharmacology of the nicotinic acetylcholine receptor. Isolation The first isolation of MLA, from ''Delphinium brownii ''Delphinium glaucum'', known by the common names Sierra larkspur, mountain larkspur, and glaucous larkspur, is a species of wildflower in the genus ''Delphinium'', which belongs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delphinium Brownii
''Delphinium glaucum'', known by the common names Sierra larkspur, mountain larkspur, and glaucous larkspur, is a species of wildflower in the genus ''Delphinium'', which belongs to the buttercup family, Ranunculaceae. It is native to western North America from Arizona to Alaska, growing in moist mountainous environments such as riverbanks and meadows. Although Ewan, in his survey of North American ''Delphinium'', treated ''D. glaucum'' and ''D. brownii'' as two separate species, some taxonomists now seem inclined to treat ''D. brownii'' as a local form of ''D. glaucum''.J. D. Olsen and G. D. Manners (1989). In ''Toxicants of Plant Origin, Vol. 1'', (P. R. Cheeke, Ed.), pp. 291–326, Boca Raton: CRC Press. However, the matter does not yet appear to be completely resolved. ''D. glaucum'' is a "tall" larkspur, which sprouts from one to several tall, stout, pale green erect stems which may approach in height. The lobed leaves are generally found only at the base of the plant. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Consolida Ambigua
''Consolida ajacis'' (doubtful knight's spur or rocket larkspur) is an annual flowering plant of the family Ranunculaceae native to Eurasia. It is widespread in other areas, including much of North America, where it is an introduced species. It is frequently grown in gardens as an ornamental for its spikes of blue, pink or white flowers. It may reach a meter in height. Since the aerial parts and seeds of ''C. ajacis'' have been found to contain diterpenoid alkaloids (see below), including the highly toxic methyllycaconitine, the plants should be considered as poisonous. Sowing In the UK, ''Consolida ajacis'' can be sowed under cover between February and April, or directly outdoors between April and May and/or late August and September. Flowering In Europe, it flowers between June and October. Chemical constituents The first alkaloid to be isolated from ''C. ajacis'' seeds was ajaconine, reported by Keller and Volker in 1914. Since that time, over thirty other structurally rel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delphinium Ajacis
''Consolida ajacis'' (doubtful knight's spur or rocket larkspur) is an annual flowering plant of the family Ranunculaceae native to Eurasia. It is widespread in other areas, including much of North America, where it is an introduced species. It is frequently grown in gardens as an ornamental for its spikes of blue, pink or white flowers. It may reach a meter in height. Since the aerial parts and seeds of ''C. ajacis'' have been found to contain diterpenoid alkaloids (see below), including the highly toxic methyllycaconitine, the plants should be considered as poisonous. Sowing In the UK, ''Consolida ajacis'' can be sowed under cover between February and April, or directly outdoors between April and May and/or late August and September. Flowering In Europe, it flowers between June and October. Chemical constituents The first alkaloid to be isolated from ''C. ajacis'' seeds was ajaconine, reported by Keller and Volker in 1914. Since that time, over thirty other structurally re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delphinium
''Delphinium'' is a genus of about 300 species of annual and perennial flowering plants in the family (biology), family Ranunculaceae, native plant, native throughout the Northern Hemisphere and also on the high mountains of tropical Africa. The genus was erected by Carl Linnaeus. All members of the genus ''Delphinium'' are toxic to humans and livestock. The common name larkspur is shared between perennial ''Delphinium'' species and annual species of the genus ''Consolida''. Molecular data show that ''Consolida'', as well as another segregate genus, ''Aconitella'', are both embedded in ''Delphinium''. The genus name ''Delphinium'' derives from the Ancient Greek word () which means "dolphin", a name used in ''De Materia Medica'' for some kind of larkspur. Pedanius Dioscorides said the plant got its name because of its dolphin-shaped flowers. Habitat Species with short stems and few flowers such as ''Delphinium nuttallianum'' and ''Delphinium bicolor'' appear in habitats like p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diterpenoid
Diterpenes are a class of chemical compounds composed of four isoprene units, often with the molecular formula C20H32. They are biosynthesized by plants, animals and fungi via the HMG-CoA reductase pathway, with geranylgeranyl pyrophosphate being a primary intermediate. Diterpenes form the basis for biologically important compounds such as retinol, retinal, and phytol. They are known to be antimicrobial and antiinflammatory. Structures As with most terpenes a huge number of potential structures exists, which may be broadly divided according to the number of rings present. Biosynthesis Diterpenes are derived from the addition of one IPP unit to FPP to form geranylgeranyl-pyrophosphate (GGPP). From GGPP, structural diversity is achieved mainly by two classes of enzymes; the diterpene synthases and cytochromes P450. Several diterpenes are produced by plants and cyanobacteria. GGPP is also the precursor for the synthesis of the phytane by the action of the enzyme geranylger ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkaloid
Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar structure may also be termed alkaloids. In addition to carbon, hydrogen and nitrogen, alkaloids may also contain oxygen, sulfur and, more rarely, other elements such as chlorine, bromine, and phosphorus.Chemical Encyclopedia: alkaloids xumuk.ru Alkaloids are produced by a large variety of organisms including , , Medicinal plant, plants, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nicotinic Acetylcholine Receptor
Nicotinic acetylcholine receptors, or nAChRs, are receptor polypeptides that respond to the neurotransmitter acetylcholine. Nicotinic receptors also respond to drugs such as the agonist nicotine. They are found in the central and peripheral nervous system, muscle, and many other tissues of many organisms. At the neuromuscular junction they are the primary receptor in muscle for motor nerve-muscle communication that controls muscle contraction. In the peripheral nervous system: (1) they transmit outgoing signals from the presynaptic to the postsynaptic cells within the sympathetic and parasympathetic nervous system, and (2) they are the receptors found on skeletal muscle that receive acetylcholine released to signal for muscular contraction. In the immune system, nAChRs regulate inflammatory processes and signal through distinct intracellular pathways. In insects, the cholinergic system is limited to the central nervous system. The nicotinic receptors are considered cholinergi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delphinium Elatum
''Delphinium elatum'' is a species of flowering plant in the buttercup family Ranunculaceae, known by the common name alpine delphinium or candle larkspur. It is native to temperate Asia and Europe, it is an erect herbaceous perennial growing to , with deeply divided leaves. It produces spikes of blue or purple flowers in summer. Taxonomy ''Delphinium elatum'' was one of the many species described by Carl Linnaeus in his 1753 work ''Species Plantarum''. Cultivation It is hardy down to , but requires a sheltered position in full sun, and deep, rich soil. All plants must be securely staked to avoid the flower heads collapsing. Gloves should be worn when handling the plant, as it can cause severe discomfort if accidentally ingested. ''Delphinium elatum'' is a source of many ornamental cultivars in a range of colours from blue and purple to pink, cream, and white. Cultivar series include Magic Fountains, Pacific giant, Dwarf Pacific, New Millennium, and Aurora (six varieties: Blue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray Crystallography
X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles and intensities of these diffracted beams, a crystallographer can produce a three-dimensional picture of the density of electrons within the crystal. From this electron density, the mean positions of the atoms in the crystal can be determined, as well as their chemical bonds, their crystallographic disorder, and various other information. Since many materials can form crystals—such as salts, metals, minerals, semiconductors, as well as various inorganic, organic, and biological molecules—X-ray crystallography has been fundamental in the development of many scientific fields. In its first decades of use, this method determined the size of atoms, the lengths and types of chemical bonds, and the atomic-scale differences among various mat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stereochemistry
Stereochemistry, a subdiscipline of chemistry, involves the study of the relative spatial arrangement of atoms that form the structure of molecules and their manipulation. The study of stereochemistry focuses on the relationships between stereoisomers, which by definition have the same molecular formula and sequence of bonded atoms (constitution), but differ in structural formula (the three-dimensional orientations of their atoms in space). For this reason, it is also known as 3D chemistry—the prefix "stereo-" means "three-dimensionality". Stereochemistry spans the entire spectrum of organic, inorganic, biological, physical and especially supramolecular chemistry. Stereochemistry includes methods for determining and describing these relationships; the effect on the physical or biological properties these relationships impart upon the molecules in question, and the manner in which these relationships influence the reactivity of the molecules in question ( dynamic stereochemis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methoxy
In organic chemistry, a methoxy group is the functional group consisting of a methyl group bound to oxygen. This alkoxy group has the formula . On a benzene ring, the Hammett equation classifies a methoxy substituent at the ''para'' position as an electron-donating group, but as an electron-withdrawing group if at the ''meta'' position. At the ''ortho'' position, steric effects are likely to cause a significant alteration in the Hammett equation prediction which otherwise follows the same trend as that of the ''para'' position. Occurrence The simplest of methoxy compounds are methanol and dimethyl ether. Other methoxy ethers include anisole and vanillin. Many alkoxides contain methoxy groups, e.g. tetramethyl orthosilicate and titanium methoxide. Such compounds are often classified as methoxides. Esters with a methoxy group can be referred to as methyl esters, and the —COOCH3 substituent is called a methoxycarbonyl. Biosynthesis In nature, methoxy groups are found on nucleosi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Configuration
The molecular configuration of a molecule is the ''permanent'' geometry that results from the spatial arrangement of its bonds. The ability of the same set of atoms to form two or more molecules with different configurations is stereoisomerism. Used as drugs, compounds with different configuration normally have ''different'' physiological activity, including the desired pharmacological effect, the toxicology and the metabolism.Everhardus Ariëns: ''Stereochemistry, the basis for sophisticated nonsense in pharmacokinetics and clinical pharmacology'', European Journal of Clinical Pharmacology 26 (1984) 663-668, . Configuration is distinct from chemical conformation, a shape attainable by bond rotations. See also * Absolute configuration Absolute configuration refers to the spatial arrangement of atoms within a chiral molecular entity (or group) and its resultant stereochemical description. Absolute configuration is typically relevant in organic molecules, where carbon is bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
