Alkaloids fluorescence

Considerable knowledge on oxazoloazine chemistry has been built up over the last 15 or so years. A major emphasis has been on the preparation of compounds for biological purposes oxazolopyrimidines may be regarded as purine analogues. Oxazoloazine ring systems are also found in antibiotics and alkaloids. Fluorescent whitening properties have also stimulated interest in azine-fused oxazoles. 

Ellipticine and derivatives can be detected at their UV-maximum of about 300 nm with a detection limit of about 1 ng. For some alkaloids, fluorescence detection is even more sensitive - allowing detection in pg amounts (excitation 305 nm, emission 470 nm). A poorly fluorescent compound such as 9-hydroxy-2-methylellipticinium acetate could be transformed to its fluorescent acetoxy derivative36. Bykadi et al. 8 also detected ellipticine fluorimetrically (excitation 360 nm, emission 455 nm). 

A recent development has been the use of two-dimensional fluorescence spectroscopy as a new method for on-Hne monitoring of bioprocesses [108]. As ergot alkaloids fluoresce, the formation of the product during cultivation can be observed by two-dimensional fluorescence spectroscopy. Substraction spectra offered on-line real time information about the productivity during the cultivation. It was possible to follow the biomass concentration on-line by monitoring the culture fluorescence intensity in the region of riboflavine and its derivatives. This is a powerful application of this new sensor since the on-Une determination of biomass is extremely complicated for this fimgus. 

Miskolczy, Z. Biczok, L. (2009). Inclusion complex formation of ionic liquids with 4 sulfonatocalixaienes studied by competitive binding of berberine alkaloid fluorescent probe. Chem. Phys. Lett., 477,80-84. 

Description of Method. Quinine is an alkaloid used in treating malaria (it also is found in tonic water). It is a strongly fluorescent compound in dilute solutions of H2SO4 (f = 0.55). The excitation spectrum of quinine shows two absorption bands at 250 nm and 350 nm, and the emission spectrum shows a single emission band at 450 nm. Quinine is rapidly excreted from the body in urine and is easily determined by fluorescence following its extraction from the urine sample. 

Acridizinium salts, lO-(phenylsuIfonyl)-synthesis, 2, 545 5-Acridone UV spectrum, 2, 156 9-Acridone acylation, 2, 352 alkylation, 2, 350 synthesis, 2, 422 Acridone alkaloids, 2, 513 9-Acridonequinones synthesis, 2, 348 Acridones fluorescence, 2, 20 mass spectrometry, 2, 134 synthesis, 2, 93, 401 from 3-arylanthranils, 2, 496 from benzotriazinones, 2, 506 tautomerism, 2, 347 Acridones, tetrahydro-synthesis... 

Emetine andcephaeline, the two major alkaloids of ipecacuanha, begin to fluoresce after treatment with iodine vapor [254], The molecular iodine, which acts as a quencher, must be removed by heating in the drying cupboard or on a hotplate... 

Fig. 1 Fluorescence scan of a mixture of alkaloids with ca. 50 ng substance per chromatogram zone morphine (1), 6-monoacetylmorphine (2) and heroin (3).

Fig. 1 Reflectance scan (A) and fluorescence scan (B) of a mixture of alkaloids with 725 ng (A) and 100 ng (B) substance per chromatogram zone. Morphine (1), codeine (2), 6-mono-acetylmorphine (3), heroin (4).

Chelerythrine crystallises from alcohol in colourless, prismatic leaflets, m.p. 207°, containing one molecule of alcohol. The alkaloid absorbs carbon dioxide from the air, becoming yellow. The solutions fluoresce blue when the alkaloid is contaminated with its oxidation product, which is formed by mere exposure of solutions to air. The salts, which are quaternary, are intensely yellow. The hydrochloride, B. HCl. HjO, forms citron-yellow needles, and the sulphate, B. H2SO4.2HjO, golden-yellow needles, sparingly soluble in water the platinichloride, B2. HaPtCl. ... 

C-Alkaloid X obtained in minute quantity as a crystalline chloride, which with nitric acid gives an intense red colour with a violet fluorescence, and orange slowly becoming red, with ceric sulphate in sulphuric acid. 

Cmchonine, C19H22ON2. This alkaloid is usually present in cinchona and cuprea barks. One of the best sources is Cinchona micrantha bark. It occurs in the crude quinine sulphate mother liquors. The mixed alkaloids recovered from these may be extracted with ether to remove quinidine and cinchonidine and the insoluble residue boiled with successive small quantities of alcohol, from which cinchonine crystallises on cooling. The crude alkaloid is neutralised with dilute sulphuric acid and the sulphate recrystallised from boiling water. Cinchonine so prepared contains quinidine, from which it may be freed by crystallisation from boiling alcohol until it ceases to exhibit fluorescence in dilute sulphuric acid. It will then still contain 10 to 15 per cent, of dihydrocinchonine, which may be removed by reprecipitation as the cuprichloride, B. 2HC1. CuClj, or by the simpler mercuric acetate process of Thron and Dirscherl. ... 

Detection. Cinchonine is sparingly soluble in all ordinary solvents, is not fluorescent in dilute sulphuric acid, is dextrorotatory, forms a soluble tartrate and hydriodide and does not give the thalleioquin reaction. Hesse s homocinchonine has been shown to be impure cinchonine. Cinchonidine, C49H22ON2. This alkaloid occurs in most varieties of cinchona bark, but especially in C. succiruhra. 

EtOH). No methoxyl is present. It forms a series of crystalline double chlorides with cadmium, zinc or copper, does not give the thalleioquin reaction, and solutions of its sulphate are not fluorescent. It is diacidie and forms two series of salts of which the nitrate, B. HNOj, crystallises in minute prisms, m.p. 196°, insoluble in water. Cinchonamine hydrochloride, B. HCl, laminae or B. HCl. HjO, cubical crystals, has been suggested for use in the estimation of nitrates. When warmed with strong nitric acid the alkaloid furnishes dinitrocinchonamine. It gives an amorphous, monoacetyl derivative, and forms a methiodide, m.p. 208 , which with silver oxide yields an amorphous methylcinchonamine. Raymond-Hamet found that cinchonamine ves typical indole colour reactions and is probably an indole alkaloid. This seems to have been... 

The amorphous alkaloids include a substance, giving fluorescent solutions in organic solvents, which is thought to be a decomposition product of ibogaine. 

This experiment33 illustrates how adjustment of pH may be used to control fluorescence and so make the determination more specific. The alkaloids codeine and morphine can be determined independently because whilst both fluoresce strongly at the same wavelength in dilute sulphuric acid solution, morphine gives a generally negligible fluorescence in dilute sodium hydroxide. The fluorescence intensities of the two compounds are assumed to be additive. 

ScHUNACK and Rochelmeyer have described such a cis/trans isomerization of an-nuloline, a weakly basic alkaloid from Lolium multifiorum LAM [9]. Irradiation with UV light after the first TLC development simultaneously causes a cis- trans and a tmns- cis isomerization, so that the SRS technique yields four blue fluorescent... 

Steroids, e.g. cholesterol, triolein, androsterone sugars, e.g. fructose, glucose, ribose amino acids, pyrimidines, purines, alkaloids 110-150°C, 2-12 h Conversion to fluorescent derivatives by heating. [5]... 

Alkaloids, e.g. reserpine, rescinnamine 105 C, 2 h Induced fluorescence (Xn > 500 nm, cut off filter). Possibly formation of 3-dehydro derivatives. [19]... 

Alkaloids, e.g. lupanine, angustifoline, sparteine, lupinine, hydroxylupanine 130°C, 17-35 h Induced blue fluorescence (Xf, = 400 nm), detection limits 10 ng. [6]... 

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