Indican

C, soluble in water and alcohol. It occurs in woad as the glucoside indican, and in mammalian urine, combined with sulphuric acid, as an ester, also called indican. It arises in the body from the bacterial decomposition of tryptophan. 

Prepared by heating ammonium mucate, or from butyne-l,4-diol and ammonia in the presence of an alumina catalyst. The pyrrole molecule is aromatic in character. It is not basic and the imino-hydrogen atom can be replaced by potassium. Many pyrrole derivatives occur naturally, e.g. proline, indican, haem and chlorophyll. 

Indian red Indican [487-60-5 Indicated reserves Indicator Indicator badges Indicator dye Indicators... 

The leaves of the indigo plant do not contain the dye as such, but in the form of its precursor, a glycoside known as indican (109). Indican [487-60-5] is the dextrose derivative (35) of indoxyl [480-93-3] (110). Indoxyl occurs also in the urine of humans as the potassium salt of indoxyl sulfonic acid (111). 

P-D-Glucopyranosyloxy)indole (or indol-3-yl p-D-glucopyranoside) trivial name indican... 

Scheme I - Palusible sequence of formation of indigotin from indican...

Fig. 2.40. Plausible sequence of formation of indigotin from indican (I), of indirubin from indoxyl and isatin (II), and of tryptanthrin from anthranillic acid and isatin (III). Reprinted with permission from A. V. Muruganandam et al. [118].

Los subindices de un compuesto idnico indican la proporcidn de iones y cationes que se necesitan para obtener compuestos el6ctricamente neutros. 

Eos nombres de las moleculas incluyen prefijos que indican el numero de itomos de cada ele-mento presentes en la molicula. 

Las ecuaciones quimicas indican la identidad y las cantidades relativas de los reactivos y productos de una reaccion quimica. Las ecuaciones quimicas deben estar equilibradas. 

Los subindices de una fdrmula quimica indican la cantidad de moles de cada elemento que hay en un mol de un compuesto. 

Obermayer s reagent chem A 0.4% solution of ferric chloride in concentrated hydrochloric acid used to test for indican in urine, with a pale-blue or deep-violet color indicating positive. o-b3r,mT-3rz re,a- 3nt n-octadecane orgchem CigHjg Colorless liquid boiling at 318°C soluble in alcohol, acetone, ether, and petroleum, insoluble in water used as a solvent and chemical intermediate. en, ak-t3 de,kan ... 

Isatis indigotica Fortune ex Lindley I. oblongata DC Da Qing (leaf) Indican, meoglucobrassicin, isatan B, indigo, glucobrassicin.33 Antibacterial, antipyretic, antiinflammatory, choleretic. 

Bilirubin A false negative may occur when the sample contains ascorbic acid concentrations of 25 mg/dl or more. The yellow/orange-to-red color produced by the presence of indican (indoxyl sulfate) is also problematic. 

Important indole derivatives (see Scheme 2) include (i) indigo, a vat dye known and widely used since antiquity, and originally obtained from indican, a (3-glucoside of indoxyl which occurs in some plants. Indigo is now prepared synthetically. Tyrian purple, a natural dye used since classical times, is 6,6 -dibromoindigo (ii) the numerous indole alkaloids, with complex derivatives such as yohimbine and strychnine (iii) tryptophan, an essential amino acid found in most proteins. Its metabolites include skatole and tryptamine and (iv) 3-indoleacetic acid, which is important as a plant growth hormone. 

Spinelli, F. 1946. Indican in cow and goat milks. Roll. Soc. ItaL Sper. 21, 210-211. 

Indican in nanirat indigo C,4H 7OftN 3H.O 100 (anhyd.) glucose indigo... 

Substances yielding indigo through hydrolysis of indican in the presence of oxygen during drying of the plant pails are found in several species of the family. 

In the period 1700 to 1900, the production of what came to be known as natural indigo was carried out on a very large scale. The indigo plant was cultivated in enormous plantations, chiefly in India and the countries of South-East Asia and America. As much as one square kilometer was needed to obtain a tonne of indigo a year [2], The reason for such a high land requirement was simply that the plant material contains barely 1 % of the dye s precursor indican, the rest being biomass. 

For thousands of years, indigo was produced from plant material containing low concentrations of indican, a precursor of the dye. Indican is split by enzymes and converted to indigo by oxidation. Indigo can be synthesized from D-glucose by genetically modified strains of coli bacteria, presumably by a process that resembles biosynthesis in plants. 

The enzyme responsible for cleaving indican is indoxyl- 3-D-glucosidase, which is formed on the plant by microorganisms. The resulting indoxyl (16), which under alkaline conditions is soluble in water, is discharged from the fermentation vat and oxidized to indigo (1) by aeration. The insoluble dye is isolated by precipitation and air drying. 

The fermentation mix can also be used directly for dyeing. The textile is impregnated with the fermenting mash and then blued by oxidation in the air. This type of dyeing was carried out with woad (Isatis tinctoria ). Pure indigo dye was not extracted from woad because of its low content of indican (15). 

Indican has been synthesized by Robertson.66 It is surprising that the intermediate LXXIV, which is very similar in structure to the enol D-glu-copyranosides shown in Table VII, could be heated in a solution of 12% potassium hydroxide in 80% methanol at 100° for 2 hours without degradation. 

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