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Tytuł:
Ostatnie postępy w syntezie alkaloidów tropanowych i pochodnych tropanu
Recent advances in the synthesis of tropane alkaloids and other tropane derivatives
Autorzy:
Sidorowicz, K.
Kropiwnicki, K.
Łaźny, R.
Powiązania:
https://bibliotekanauki.pl/articles/171941.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
synteza
alkaloidy tropanowe
pochodne tropanów
synteza stereoselektywna
synthesis
tropane alkaloids
tropane derivatives
stereoselective synthesis
Opis:
Tropane alkaloids are a long-known class of compounds possessing an 8-azabicyclo[ 3.2.1]octane skeleton. Many tropane alkaloids posses biological activity (anticholinergic, anti-Parkinsonian, hypotensive), and as such had a significant influence on medicine and played a notable role in the development of organic chemistry [1]. The most known representatives of biologically active tropane alkaloids are: cocaine, atropine, scopolamine, ecgonine, and Bao Gong Teng A. A number of natural tropane alkaloids are chiral compounds, whose preparation in optically active forms is still a big challeng [2]. The biological activity of enantiomers often differs depending on their configurations. Alkaloids are a subject of an intensive research: scopus database contains nearly 200 thousand publications with the word „alkaloid”, and almost 4,500 publications with the phrase „tropane alkaloids” (about half of them have appeared in the last ten years). About 55 papers are devoted to stereoselective synthesis of tropane derivatives in 2000-2015. About half of this concernes stereoselective methods. The organic synthesis of alkaloids has a long history and numerous synthetic approaches to the tropane skeleton have been developed, from the classical synthesis of tropinone by Willstätter at the beginning of the XX century, to more recent developments dealing with asymmetric deprotonation of tropinone with chiral lithium amide bases for the enantioselective synthesis of a range of tropanes [3, 4]. Owing to extensiveness of the field, the current review presents the most interesting, from a synthetic point of view, approaches to tropane derivatives and tropane analogues. Most of the methods of synthesis are long (often several steps), time- and recourses-intensive, and often required elaborate and hardly available starting materials. But there are also notable exceptions, based on the asymmetric deprotonation approach; e.g., from the syntheses of cocaine described in this article, the most efficient one was reported by Lee in 2000 [5]. The concise synthesis (6 steps) gave the unnatural enantiomer of cocaine starting from commercially available tropinone in 78% overall yield. This approach allows to obtain both enantiomers and racemate, by changing type of one reactant only. However, most strategies provide only one enantiomer or racemic mixture of an alkaloid. As can be seen, despite of advances in chemicall science, there is no general way to synthesize majority of the representatives of this group of structurally related compounds.
Źródło:
Wiadomości Chemiczne; 2015, 69, 11-12; 1019-1045
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nowe substancje psychoaktywne : katynon i jego pochodne
New psychoactive substances : cathinone and its derivatives
Autorzy:
Kurpet, Katarzyna
Chwatko, Grażyna
Powiązania:
https://bibliotekanauki.pl/articles/172450.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
katynon
alkaloidy
narkotyki
czuwaliczka jadalna
nowe substancje psychoaktywne
dopalacze
cathinone
alcaloids
drugs
khat
new psychoactive substances
designer drugs
Opis:
Cathinone is the major alkaloid found in the Catha edulis plant. The chemical structure of the cathinone is similar to amphetamine, and the difference in their structure is the presence of the ketone group in the beta side chain position. Synthetic derivatives belong to the novel group of psychoactive substances called “legal highs” or designer drugs. Synthetic cathinones are formed by modifications of the cathinone molecule consisting in the attachment of various substituents to the benzene ring and side chain and the use of a nitrogen atom to build the pyrrolidine ring. On this basis, these relationships can be divided into four main groups: N-alkylated, N-pyrrolidinyl, 3,4-methylenedioxy-N-alkylated and 3,4- methylenedioxy-N-pyrrolidinyl derivatives [1-2]. The simplicity of the synthesis and the availability of substrates favors the continuous process of modifying the cathinone derivatives covered by legal control. Therefore, continuous improvement of cathinone detection methods is extremely important for forensic chemistry. Cathinones easily penetrate the blood-brain barrier, inhibiting the uptake of neurotransmitters, including dopamine, serotonin or noradrenaline, and increase their concentration in the synaptic cleft. This leads to increased monoaminergic transmission in the central as well as in the peripheral nervous system, which entails a number of adverse effects [3]. In this article we described the pharmacokinetics, postulated neurochemical mechanisms and pharmacological and toxicological effects of cathinones. The current legal status of cathinone derivatives and selected synthesis methods was also discussed. We believe these information contribute improving public health and safety.
Źródło:
Wiadomości Chemiczne; 2019, 73, 7-8; 461-489
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Alkaloidy kory chinowej : małe cząsteczki, które wiele mogą
Cinchona alkaloids : small hardworkers
Autorzy:
Kacprzak, K.
Czarnecki, P.
Powiązania:
https://bibliotekanauki.pl/articles/172207.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
chinina
alkaloidy kory chinowej
chinidyna
synteza asymetryczna
rozdział enancjomerów
chiralność
quinine
cinchona alkaloids
quinidine
asymmetric synthesis
enantiomer separation
chirality
Opis:
Cinchona alkaloids comprising quinine, quinidine, cinchonidine and cinchonine as the major members constitute a unique class of quinoline alkaloids with tremendous impact on human civilization (Section 1). The odyssey of Cinchona alkaloids began with the discovery of their antimalarial properties followed by antiarrhytmic action of quinidine. Currently medicinal chemistry of Cinchona alkaloids derivatives develops rapidly and many other activities such as cytotoxic, multidrug resistance inhibitory have been demonstrated (Section 5) [5]. Beside medicine Cinchona alkaloids gave also the fundaments of stereochemistry and asymmetric synthesis. An extraordinary catalytic potency of parent and modified Cinchona alkaloids (deserving privileged catalyst classification) include more than 50 types of diverse stereoselective reactions, with few spectacular such as asymmetric dihydroxylation of alkenes or heterogeneous α-ketoesters hydrogenation (Section 3) [3]. Last but not least the portfolio of applications of Cinchona alkaloids includes resolution of racemates by diastereomeric crystallization or by the use of Cinchona- -based chiral stationary phases for ion-exchange enantioselective chromatography and other recognition or sensing systems (Section 4) [166]. Easy transformation of Cinchona alkaloids (for example by click chemistry) into other chiral and modular building blocks together with current pressure on a more intense exploration of sustainable products make cinchona alkaloids of primary importance for modern synthetic, catalytic and medicinal chemistry. The aim of this review which covers over 200 references is to briefly summarize all aspects of Cinchona alkaloid chemistry and biology with the special emphasis on new applications.
Źródło:
Wiadomości Chemiczne; 2013, 67, 5-6; 443-493
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-3 z 3

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