Alkaloids, liquid

Verpoorte, R. Alkaloids/Liquid Chromatography. In Encyclopedia of Separation Science Wilson, I.D., Adlard, E.R., Cooke, M., Poole, C.E., Eds. Academic Press New York, 1949-1956 Vol. 5. 

C10HJ4N2. When pure nicotine is a colourless liquid, b.p. 247 C, but darkens on exposure to air and light. Crude nicotine contains smalt amounts of other alkaloids, but ( —)-nicotine is the principal component. 

Colourless liquid with a characteristic ammo-niacal smell m.p. 9 C, b.p. 106°C. Miscible with water. It is present in pepper as the alkaloid piperine from which it can be obtained by healing with alkali. It can also be prepared by the reduction of pyridine, either electrolytically or by other means. Piperidine is a strong base, behaving like the aliphatic amines. 

Constitution. Pelletierine behaves as a secondary amine and the oxygen atom of the alkaloid is present in the form of an aldehyde group, since the base yields an oxime, convertible by the action of phosphorus pentachloride into a nitrile, b.p. 104-6°/13 mm., which is hydrolysed by caustic potash in alcohol to an acid, the ethyl ester of which is Loffler and Kaim s ethyl -2-piperidylpropionate. Pelletierine is not directly oxidisable to this acid. It also yields a liquid hydrazone, b.p. 130°/20 ram., which with sodium in alcohol at 136-70° reduces to dZ-eoniine. These reactions are explained by the following formulas, in which pelletierine is represented as -2-piperidylpropionaldehyde. 

Constitution. The alkaloid yields a crystalline semicarbazone, m.p. 169°, a liquid hydrazone, b.p. 154-5°/29 mm., and a liquid oxime, b.p. 160°/12 mm., from which a crystalline picrate, m.p. 106°, can be prepared. The methiodide crystallises in cubes, m.p. 156°. On oxidation with chromic acid in sulphuric acid solution the base yields A -methylpiperdine-... 

Simple Bases. In addition to the alkaloids proper, 1 4-TETRAMETHYLDiAMiNoBUTANE, MCjN. (CHj) . NMCj, has been found in Hyoscyamus muticus by Merck and in H. reticulatus by Konovalova and Magidson. It was described by Willstatter and Heubner as a colourless liquid, 0-7941, b.p. 169°, with a pungent, acrid taste. The... 

Strychnicine. This alkaloid, isolated from nux-vomica leaves grown in. lava, forms needles, m.p. 240° dec.), and is characterised by the following colour reaction. When sodium hydroxide solution is added drop by drop to a solution of a salt of the alkaloid in water, the precipitate formed dissolves on addition of more alkali, forming an orange-coloured liquid which develops a violet colour on addition of hydrochloric acid. Strychnicine is scarcely poisonous, but is said to produce tetanus in frogs. 

Ephedrine also oeeurs in the leaves of the yew tree [Taxus baccata) and in Sida rhombifolia Linn, whilst Stockman s cathine from Catha edulis Forsk has been shown by Wolfes to be d-nor- -ephedrine. Ghosh, Chopra and Dutt state that the bark of Moringa pterygosperma Gaertn. contains two alkaloids similar to ephedrine in pharmacological action. The more active of the two, moringinine, is amorphous the other is a liquid but jdelds a crystalline hydrochloride, C,H. HCl, m.p. 254-4°, + 1-8°, a picrate, m.p. 195°, and an aurichloride, m.p. 170-8°. 

Sempervirine, C19H1JN2. H2O. From the alkaline liquid, after removal of gelsemine by ether, Moore observed that amyl alcohol extracted two amorphous alkaloids, of which the more basie was probably Thompson s gelseminine. From this material erystalline sempervirine was obtained by Stevenson and Sayre, and later by Chou, but a formula was first assigned to it by Hasenfratz. It forms yellow needles, m.p. 228°, from ehloroform, or orange-yellow to brown-red crystals, m.p. 258-260°, from alcohol, [a]D 0°, pK value 10-6. The salts crystallise well B. HCl. 2H2O, yellow prisms, m.p. > 300° B. HBr. 2H2O, m.p. 325°... 

Hofmeister has recorded the presence of a liquid toxic alkaloid, temuline, C HjjONj, in L. temulentum. ... 

Hclvclla csculcnta. Liquid, volatile alkaloid, CgHi2(i4)N2 picrate, m.p. 145-150° (Aye, Arch. Pharm., 1933, 271, 537). 

Contains Nitrogen.—First test the original solid ni liquid by heating in a hard-glass tube with soda-lime (p. 2), and notice if the smell is that of ammonia (ammonia salt, amide or cyanide), an amine (amine or amino-acid) or a pyridine base (alkaloid). 

Damascenine, CjqHj3N03, is a nitrogenous compound of an alkaloidal nature, which is present in the oil of Nigella damascena to the extent of about 9 per cent. It can be extracted from the oil by shaking it with dilute hydrochloric acid, rendering the aqueous liquid alkaline and extracting the alkaline liquid with petroleum ether. 

Alkaloids, e.g. cocaine, ecgonine, benzoylecgonine, ecgonine methyl ester 280 °C, 8 min or 260°C, 10-30 min Pale blue induced fluorescence (Xn > 390 nm, cut off filter), fluorescence amplification by a factor of 2 on dipping in liquid paraffin solution detection limits <10 ng. [13]... 

The role of reversed micelles in the manufacture of fine chemicals with enzymes also needs to be assessed and analysed. An outstanding example is lipase catalysed interesterification to produce cocoa butter substitute from readily available cheap materials (Luisi, 1985). This example of reversed micelles is sometimes referred to as a colloidal solution of water in organic systems. A number of water insoluble alkaloids, prostanoids, and steroids have been subjected to useful transformations (Martinek et al., 1987). Peptide synthesis has also been conducted. The advantages of two liquid phases are retained to a very great extent the amount of water can be manipulated to gain advantages from an equilibrium viewpoint. 

Scholten, A. H. M. T. and Frei, R. W., Identification of ergot alkaloids with a photochemical reaction detector in liquid chromatography, /. Chromatogr., 176, 349, 1979. 

Results of liquid phase NMR measurements (Table 4) show that only the real substrates influences the proton shift of H3 and H9 protons of CD. These data confirmed the liquid phase interaction between the diketones and the chiral modifier. No effect of dummy substrates (ethyl acetate, acetone, etc.) was observed. No direct connection was found between kinetic data (reaction rate and optical yield) and NMR proton shift. Liquid phase NMR measurements confirmed the interaction of both 2,3-butandione and 3,4-hexanedione with the alkaloid used. 

The high-performance liquid chromatography (HPLC) determination of quinolizidine alkaloids in Radix Sophora flavescens was assisted by using tris(2,2 -bipyridyl)ruthenium(n) electrochemoluminescence <2004MI237>. Tandem HPLC-MS techniques have allowed the development of a sensitive and specific method for the determination of sophocarpine, matrine, and sophoridine in rabbit plasma <2005MI1595>. 

Wu and Sun have presented a versatile procedure for the liquid-phase synthesis of 1,2, ,4-tctrahydro-/i-carbolines [77]. After successful esterification of the MeO-PEG-OH utilized with Fmoc-protected tryptophan, one-pot cyclocondensations with various ketones and aldehydes were performed under microwave irradiation (Scheme 7.68). The desired products were released from the soluble support in good yields and high purity. The interest in this particular scaffold is due to the fact that the l,2,3,4-tetrahydro-/f-carboline pharmacophore is known to be an important structural element in several natural alkaloids, and that the template possesses multiple sites for combinatorial modifications. The microwave-assisted liquid-phase protocol furnished purer products than homogeneous protocols and product isolation/ purification was certainly simplified. 

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