- Alkaloid
"This article is about the chemical compounds alkaloids. For the
pharmaceutical company in theRepublic of Macedonia seeAlkaloid (company) .Alkaloids are naturally occurring
chemical compound s containing basicnitrogen atoms. [GoldBookRef|title=alkaloids|file=A00220|year=1995] The name derives from the wordalkaline and was used to describe any nitrogen-containing base. Alkaloids are produced by a large variety of organisms, includingbacteria , fungi,plant s, andanimal s and are part of the group ofnatural products (also calledsecondary metabolite s). Many alkaloids can be purified from crude extracts byacid-base extraction . Many alkaloids are toxic to other organisms. They often have pharmacological effects and are used asmedication s andrecreational drug s. Examples are thelocal anesthetic andstimulant cocaine , the stimulantcaffeine ,nicotine , theanalgesic morphine , or theantimalarial drug quinine . Some alkaloids have a bitter taste.Alkaloid classifications
Alkaloids are usually classified by their common molecular precursors, based on the
metabolic pathway used to construct the molecule. When not much was known about thebiosynthesis of alkaloids, they were grouped under the names of known compounds, even some non-nitrogenous ones (since those molecules' structures appear in the finished product; the opium alkaloids are sometimes called "phenanthrenes", for example), or by the plants or animals they were isolated from. When more is learned about a certain alkaloid, the grouping is changed to reflect the new knowledge, usually taking the name of a biologically-important amine that stands out in the synthesis process.*
Pyridine group:piperine ,coniine ,trigonelline ,arecoline ,arecaidine ,guvacine ,cytisine ,lobeline ,nicotine ,anabasine ,sparteine ,pelletierine .
*Pyrrolidine group:hygrine ,cuscohygrine ,nicotine
*Tropane group:atropine ,cocaine ,ecgonine ,scopolamine ,catuabine
*Quinoline group:quinine ,quinidine ,dihydroquinine ,dihydroquinidine ,strychnine ,brucine ,veratrine ,cevadine
*Isoquinoline group: opium alkaloids (papaverine ,narcotine ,narceine ),sanguinarine ,hydrastine ,berberine ,emetine , berbamine, oxyacanthine
*Phenanthrene alkaloids : Theopium alkaloids (morphine ,codeine ,thebaine )
*Phenethylamine group:mescaline ,ephedrine ,dopamine
*Indole group:
**Tryptamine s:serotonin , DMT,5-MeO-DMT ,bufotenine ,psilocybin
**Ergoline s (theergot alkaloids):ergine ,ergotamine ,lysergic acid ,LSD
**Beta-carboline s:harmine , harmaline,tetrahydroharmine
** Yohimbans:reserpine ,yohimbine
**Vinca alkaloids :vinblastine ,vincristine
** "Mitragyna speciosa " alkaloids:mitragynine ,7-hydroxymitragynine
** "Tabernanthe iboga " alkaloids:ibogaine ,voacangine ,coronaridine ,18-methoxycoronaridine
** "Strychnos nux-vomica " alkaloids:strychnine ,brucine
*Purine group:
**Xanthine s:caffeine ,theobromine ,theophylline
*Terpenoid group:
**Aconite alkaloids:aconitine
**Steroid alkaloids (containing a steroid skeleton in a nitrogen containing structure):
***solanum (e.g. potato and tomato) alkaloids (solanidine ,solanine ,chaconine )
***veratrum alkaloids (veratramine ,cyclopamine ,cycloposine ,jervine ,muldamine ) [ http://www.ansci.cornell.edu/plants/toxicagents/steroid.html,]
*** newt alkaloids (samandarin )
*** othersconessine
* Quaternary ammonium compounds:muscarine ,choline ,neurine
* Miscellaneous:capsaicin ,cynarin ,phytolaccine ,phytolaccotoxin Physicochemical properties
Low-molecular weight alkaloids without
hydrogen bond donors such ashydroxy group s are often liquid at room temperature, examples arenicotine ,sparteine ,coniine , andphenethylamine .The basicity of alkaloids depends on the
lone pair s of electrons on theirnitrogen atoms. As organic bases, alkaloids form salts withmineral acid s such ashydrochloric acid andsulfuric acid andorganic acid s such astartaric acid ormaleic acid . These salts are usually more water-soluble than theirfree base form.See also
*
Amine
*Base (chemistry)
*Natural products
*Secondary metabolite References
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Alkaloid — Al ka*loid ([a^]l k[.a]*loid), Alkaloidal Al ka*loid al ([a^]l k[.a]*loid al), a. [Alkali + oid: cf. F. alcalo[ i]de.] 1. Pertaining to, resembling, or containing, alkali. [1913 Webster] 2. of or pertaining to alkaloids. [WordNet 1.5] … The Collaborative International Dictionary of English
Alkaloid — Al ka*loid ([a^]l k[.a]*loid), n. (Chem.) An organic base, especially one of a class of nitrogen containing substances occurring ready formed in the tissues of plants and the bodies of animals. [1913 Webster] Note: Alkaloids all contain nitrogen … The Collaborative International Dictionary of English
alkaloid — (n.) 1831, from ALKALI (Cf. alkali) (q.v.) + OID (Cf. oid). A general term applied to basic compounds of vegetable origin, bitter in taste, and having powerful effects on the animal system [Flood]. As an adjective by 1859 … Etymology dictionary
alkaloid — {{/stl 13}}{{stl 8}}rz. mnż I, D. u, Mc. alkaloididzie, zwykle w lm {{/stl 8}}{{stl 7}} zasadowy związek organiczny pochodzenia roślinnego zawierający azot, zwykle nierozpuszczalny w wodzie, np. morfina, strychnina, chinina, nikotyna; odznacza… … Langenscheidt Polski wyjaśnień
alkaloid — [al′kə loid΄] n. [ ALKAL(I) + OID] any of a number of heterocyclic, colorless, crystalline, bitter organic substances, such as caffeine, morphine, quinine, and strychnine, having alkaline properties and containing nitrogen: they are found in… … English World dictionary
alkaloid — /al keuh loyd /, Biochem., Chem., Pharm. n. 1. any of a large class of organic, nitrogen containing ring compounds of vegetable origin and sometimes synthesized, some of which are liquid but most of which are solid, that have a bitter taste, that … Universalium
Alkaloid — Strukturformel des Alkaloids Morphin Alkaloide (Wortbildung aus arabisch al qualja: „Pflanzenasche“ und griechisch oides: „ähnlich“) sind natürlich vorkommende, chemisch heterogene, meist basische, stickstoffhaltige organische Verbindungen des… … Deutsch Wikipedia
alkaloid — UK [ˈælkəˌlɔɪd] / US noun [countable/uncountable] Word forms alkaloid : singular alkaloid plural alkaloids chemistry a substance found in plants that is used in drugs and poisons. Morphine, nicotine, and strychnine are all alkaloids … English dictionary
alkaloid — al|ka|loid1 [ ælkə,lɔıd ] noun count or uncount SCIENCE a substance found in plants that is used in drugs or as a poison alkaloid al|ka|loid 2 [ ælkə,lɔıd ] adjective AMERICAN TECHNICAL another word for ALKALINE … Usage of the words and phrases in modern English
alkaloid — alkaloidas statusas T sritis chemija apibrėžtis Fiziologiškai aktyvi azoto turinti bazė, randama augaluose. atitikmenys: angl. alkaloid rus. алкалоид … Chemijos terminų aiškinamasis žodynas