Quina alkaloids

Camphor- 10-sulfonic acid, 62 (S)-2-(l-Hydroxy-1-methylethyl)-pyrrolidine, 146 a-Methylbenzylamine, 185 Quina alkaloids, 264 Cycloaddition reactions 2-Oxazolidones, chiral, 225 Cyclopropanation Diiodomethane-Diethylzinc, 276 Simmons-Smith reagent, 275 Deprotonation Lithium amides, chiral, 159... 

Lithium butyldimethylzincate, 221 Lithium sec-butyldimethylzincate, 221 Organolithium reagents, 94 Organotitanium reagents, 213 Palladium(II) chloride, 234 Titanium(III) chloride-Diisobutylalu-minum hydride, 303 Tributyltin chloride, 315 Tributyl(trimethylsilyl)tin, 212 3-Trimethylsilyl-l, 2-butadiene, 305 Zinc-copper couple, 348 Intramolecular conjugate additions Alkylaluminum halides, 5 Potassium t-butoxide, 252 Tetrabutylammonium fluoride, 11 Titanium(IV) chloride, 304 Zirconium(IV) propoxide, 352 Miscellaneous reactions 2-(Phenylseleno)acrylonitrile, 244 9-(Phenylseleno)-9-borabicyclo[3.3.1]-nonane, 245 Quina alkaloids, 264 Tributyltin hydride, 316 Conjugate reduction (see Reduction reactions)... 

Quina alkaloids, 264 Sodium hydroxide-Triethyl(2-methyl-butyl)am onium bromide, 239 Sodium hydroxide-N-(p-Trifluoro-methylbenzyl)cinchoninium bromide, 325... 

The important role played by the quinicines (rubatoxanones, quina-toxines) in the syntheses of the dihydrocinchona alkaloids and the possibility that such substances might be used for the preparation of products approaching quinine in therapeutical interest, has led to the production of a large number of quinolyl ketones of various types and the corresponding secondary alcohols, and other derivatives obtainable from them, of which mention may be made of Rubtzov s syntheses of several isomerides of dihydroquinine. ... 

The central. CHOH. group in the cinchona alkaloids seems to be essential to anti-malarial activity Conversion into quinicines [quinatoxines (I) — (VII)] destroys activity and so do such changes as. CHOH. — . CHCl. (cinchona chlorides) or. CHOH. — . CHj. (deoxy-cinchona bases) or. CHOH. — . CO. quina-ketones), or acylation of the hydroxyl group except in the case of quinine ethylcarbonate. 

Tetrahydro- and l,2,3,4,6,7,8,9-octahydro-ll//-pyrido[2,l-fe]quina-zolin-ll-ones and their 6-arylhydrazino derivatives (134) are key intermediates in the total synthesis of rutaecarpine alkaloid (409) and its derivatives (183) (85JHC1373 87JHC1045). 

Leaves of Cinchona succirubra Pav. from a trial plantation in the north of Thailand have been reported to contain the typical bases of quinoline alkaloids (cinchonine, cinchonidine, quinidine, quinine, di-hydroquinidine, and dihydroquinine) together with the indole bases quina-mine and 3-epiquinamine (97,98). 10-Methoxycinchonamine (92) has also been isolated from this plant for the first time. Except for the inclusion of alkaloid 92, the alkaloid pattern in C. succirubra is the same as that in the cross-species C. succirubra x C. ledgeriana from Guatemala. 

The ordinary dose of Dispulphate of Quinia is two grains three times a day. As much as ten grains or more may be given in particular cases. (C inidia is an alkaloid found in some kinds of bark, which much resembles Quina. What has been called Amorphous Quinine is impure Quinidia. It may be prescribed and used like Quinine.)... 

The cinchona tree, from the bark of which these alkaloids are obtained, was originally found only on the eastern slope of the Andes in South America. The cultivation of this species, and other species of the same genus, was introduced into Java, India, Ceylon, Jamaica and Australia. At present the production of bark in Java is greater than in any other country. As early as 1639 the cinchona bark was introduced into Europe but it was not until 1792 that an impure alkaloid was isolated and a little later given the name quina. In 1820 this impure alkaloid was separated into two compounds named quinine and cinchonine. The bark contains about 3 per cent quinine combined with acids, tannic and quinic, from which it is set free by the action of lime. The free base is then extracted with petroleum ether or... 

Makino et al. described a pathway to quinazolinones utilizing a resin-bound amine, treatment of which with 2-methoxycarbonyl phenylisothiocyanate formed resin 147, which subsequently cydized in the presence of TFA to form the quina-zohnone core structure 151 [190]. Quinazoline alkaloids have been synthesized by cychzation of amidine intermediate 148 [191]. A two-step reaction on a sohd support involving cyclocondensation of ethyl oxalate 149 with benzamide and subsequent cleavage employing trimethylsilyl iodide also provided a quinazohne [192]. 

Quinoline is a high-boiling liquid isoquinoUne is a low-melting solid each has a sweetish odour. Both bases have been known for a long time quinoline was first isolated from coal tar in 1834, isoquinoUne from the same source in 1885. Shortly after the isolation of quinoline from coal tar, it was also recognised as a pyrolytic degradation product of cinchonamine, an alkaloid closely related to quinine, from which the name quinoline is derived the word quinine, in turn, derives from quina, a Spanish version of a local South American name for the bark of quinine-containing Cinchona species. 

Cmchona alkaloids. Indole alkaloids (cinchonamine group) and quinoline alkaloids (cinchonine group), only the latter group is of therapeutic significance. C. a. are isolated from Cinchona bark (Jesuit s bark Cin-chonae cortex). The name is derived from the Indian word quina (bark). The drug consists of the dried tube... 

Contents O. Tanaka and R. Kasai Saponins of Ginseng and Related Plants. — E. Fujita, M. Node Diterpenoids ofRabdosia Species. — S. Johne The Quina-zoline Alkaloids. 

Cinchona plants yielded a crucial phytochemical resource to nineteenth century European people involved in trade and colonization of tropical lands - quinine [52], Before quinine, malaria was a major health issue in the new world, lowering quality of life by causing severe discomfort and even death. Quinine is an alkaloid present in the bark of several Cinchona species known as quina quina by native populations. It is most concentrated in Cinchona calisaya however, the most widely known quina quina plant became Cinchona officinalis officinalis means medical herb ). Besides quinine, Cinchona plants produce other antimalarial alkaloids, namely, quinidine, cinchonine, and cinchonidine. Cinchona alkaloids can be found in other Rubiaceae genera as well, as described for Remijia peruviana [53], Cinchona alkaloids have other bioactivities besides antimalarial. Quinine has been used to treat cramps [54]. Cinchonine is an inhibitor of MDR [55]. MDR is a detoxification mechanism present in certain cancer cell lines that renders them less sensitive to chemotherapeutic medications. Administration of cinchonine along with chemotherapeutic agents would result in better efficiency of treatment oti MDR cancer cells. 

Alkaloids are classified into two main groups heterocyclic and non-heterocyclic. In this work, authors will only deal with the heterocyclic alkaloids that have a quinoUne nucleus (tryptophan derivatives), which include the alkaloids of quina, and the group of diverse alkaloids, specifically the xanthine bases or purine alkaloids. 

Quina, Cinchona sp., is a tree native to South America, where people use the bark from trunks and branches because they contain quinoline alkaloids (quinine) and bitter principles. They are used in cosmetics because of their tonic, asbingent, anti-dandruff and hair growth-stimulating properties (Council of Europe, 1989). The use of quinine and quinine salts is restricted to shampoos and hair lotions (Annexe III, Part 1). 

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