Cupreine

Cinchonine, cinchonicine, cinchonidine. Cinchotine, cinchamidine, cinchonamine. Cupreine. 

Like other alkaloids of this group, quinine forms molecular compounds with a variety of organic substances. With benzene and toluene it produces compounds of the formulae B. CgHg and B. C,Hg respectively, with phenol it gives the crystalline product B. CgHjOH, and similar combinations with polyhydric phenols, ethers, aldehydes and ketones are known. One of the most characteristic of these substances is cupreine-quinine, a combination of the two alkaloids, obtainable from cuprea bark, and at first regarded as a new alkaloid, and named homoquinine. ... 

It is sparingly soluble in ether or chloroform, readily in alcohol or solutions of caustic alkalis, but not in ammonia, and gives the thalleioquin reaction. Cupreine is a diacidic base the neutral sulphate, Bj. H2SO4, forms colourless anhydrous needles, m.p. 257 , soluble in 813 parts of water at 17 the iwiid sulphate, B. HjSO. HjO, crystallises in prisms and is soluble in... 

Hydrocupreine (Dihydrocupreine), CigH2402N2. This alkaloid does not occur naturally, but can be produced by demethylating dihydroquinine or reducing cupreine. It crystallises from dilute alcohol in minute needles or from a mixture of chloroform and benzene in warty masses, m.p. 230° (dec.) with some sintering at 185-200°, is readily soluble in chloroform, alcohol or hot benzene, and much less so in ethyl acetate, insoluble in light petroleum, — 155-5° (G. and Wi ° 148-7°... 

The alkyl ethers of dihydrocupreine (II) are known to exhibit local anassthetic action, which appears to be at a maximum at woamyldihydro-cupreine, but local anassthetic action in this group does not depend on the intact quinuclidine nucleus, since woamyldihydrocupreicine (VII) is more potent than isoamyldihydrocupreine (II), producing local anassthesia in the cornea of the rabbit at 1 in 2,000 compared with cocaine at 1 in 50. ... 

Glucose. There are four basic principles utilized for glucose analysis. The most widely used depends upon the reduction of some element such as copper or iron. This is the principle of the Folin-Wu method, the ferricyanide method, used on the Autoanalyzer, and the cupreine ( ) method used on the SMA-12/60. 

This problem removes the cupreine method as an acceptable procedure for the Pediatric Laboratory for glucose analysis under any circumstances ... 

J.M. McCord and I. Fridovich, Superoxide dismutase. Enzymic function for erythrocuprein (hemo-cuprein). J. Biol. Chem. 244, 6049-6055 (1969). 

J.R. Kimmel, H. Markowitz, and D.M. Brown, Some chemical and physical properties of erythro-cuprein. J. Biol. Chem. 234, 46-50 (1959). 

Cupreines and cupreidines are pseudoenantiomers of Cinchona alkaloids with the replacement of quinoline C(6 )-OCH3 with an OH-group. The result is availability of an additional hydrogen-bonding moiety. 

The nitroaldol reaction, particularly involving ketones has been relatively unexplored in the field of asymmetric organocatalysis. Employing cupreines and cupreidines as catalysts, Deng [63] presented an enantioselective nitroaldol reaction of a-ketoesters... 

The Deng group identified QN-derived thiourea 121 and QD -derived thiourea 124 to be also efficient promoters of enantio- and diastereoselective Diels-Alder reactions between the 2-pyrone diene 3-hydroxypyran-2-one and the dienophiles fumaronitrile, maleonitrile as well as acrylonitrile, while various C9-hydroxy acylated and alkylated (dihydro)cupreines and (dihydro)cupreidines failed for the same reactions under identical conditions (e.g., 97% yield, 15% ee, 64 36 endoxxo) [289], Catalysts 121 and 124 (5mol% loading), however, produced the corresponding Diels-Alder adducts 1-3 with synthetically useful enantioselectivities (85-... 

To obtain these products selenium dioxide is allowed to react with the hydrogenated cinchona alkaloids or their derivatives in the presence of concentrated sulphuric acid and the products obtained are diluted with water and boiled. Selenohydroquinine is prepared from hydro-quinine sulphate or hydroquinine sulphuric ester, and forms yellow needles which remain unchanged below 235° C. selenoethylhydro-cupreine forms yellow needles, 5l.pt. 233° to 23-1° C., and selenohydro-cupreine separates as small, orange-coloured needles, w hich are unmelted below 235° C. The products are of use therapeutically. 

Arsenic Derivative op Cupreine. Dihydrocupreine-5-azobenzene-p-arsinic acid,... 

Cupreine. (hydroxycinchonine). C19H2202N2 2H20. One of the cinchona alkaloids. 

Figure 13.2 Structural features of cinchona alkaloid molecules (QN, quinine QD, quinidine CN, cinchonine CD, cinchonidine CPN, cupreine CPD, cupreidine).

It may be questioned whether all these proteins are separate entities. There are many similarities between hemocuprein and erythrocupiein, and also between hepatocuprein, horse liver copper protein, and human hepato-cuprein. Porter suggested that the erythrocuprein of Markowitz et al. (P14), cerebrocuprein I, and human hepatocuprein may be identical proteins, although he recognizes some differences between them. 

Contents U.Weser Structural Aspects and Biochemical Function of Erythro-cuprein. - R.R.Crichton Ferritin. -M.Llinas Metal-Polypeptide Interactions The Conformational State of Iron Proteins. - F.L.Siegel Calcium-Binding Proteins. 

Since the discovery of superoxide dismutase (SOD) by McCord and Fridovich (Ml9), increasing numbers of papers have been published concerning the structural and functional aspects of this enzyme. Historically, a variety of SODs were reported as copper-containing proteins hemocuprein from bovine blood (M2), hepatocuprein from horse liver (M28), cerebrocuprein from human brain (P10), and ery throcupurein from human and beef erythrocytes (M9). Carrico and Deutsch (C2) gave the name cytocuprein to these proteins because the cupreins from various organs were found to be essentially identical. Cytocuprein was found to... 

Our knowledge of the structural properties and enzymic function of a large number of copper proteins has accumulated during the last few decades. The main results have been comprehensively reviewed 1—4) or presented at symposia (5—54). This survey is devoted to erythro-cuprein, one of the most actively studied copper proteins. Erythrocu-prein is sometimes called haemocuprein, hepatocuprein, cerebrocuprein, cytocuprein, or erythro-cupro-zinc protein. Alternatively, the name superoxide dismutase has been suggested as descriptive of its activity the enzyme-catalyzed disproportionation of anionic monovalent superoxide radicals. However, whether or not the enzymic reaction is specific for Oi- still needs to be investigated1). Thus, the name erythrocuprein is used throughout this review. 

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