Indigo substituted

The sodium salts of the sulphonic acids of various indulines come into commerce under the names of Fast Blues, Blackley Blue, Indigo substitute, c. The diflerence of the various marks depends on the shade of the induline sulphonated and the number of sulpho-groups introduced. 

Tile basic chromophors of indigo and of some tetraazafulvalenes are very similar and therefore the frontier orbitals are comparable (90JPC949). PPP calculations on the 1,3,5,7-tetraazafulvalene 90 (R = Me) showed a good agreement with its UV/VIS spectrum. Tlie substitution of both methyl-sulfanyl groups in 90 by diethylamino/piperidino moieties led to a hypso-chromic shift of about 45 nm. 

At the present time we have not attempted to isolate a-thioisatin, the presumed intermediate in the synthesis of indigo. However, it is immediately apparent that if this intermediate could be isolated or intercepted in situ, then many possibilities would open up for the conversion of this compound directly into other indole derivatives. It is also apparent that it should be possible to carry out the reaction with substituted thioureas. We shall be exploring these possibilities. 

Table 4.2 UV/visible spectral data (Xmax values in nm) for solutions of some symmetrical di-substituted indigo derivatives 57 and 57a-d in 1,2-dichloroethane.

Orthophthalic acid is made by the oxidation of naphthalene (1) with H2SCL fuming heated, in the presence of mercuric sulfate —SO2 is also formed and recovered (2 ) with air in the presence of vanadium pentoxide at 450 to 520°C. Orthophthalic acid also is formed when benzene compounds containing carbon ortho-substituted groups are oxidized. Orthophthalic arid is used in the manufacture of indigo and other dyes,... 

Partly owing to their high price, other jvat dyestuffs are not used either in conjunction with indigo or as substitutes for it. 

Toluene Dioxygenase Indigo or Prostaglandins from Substituted Benzenes via cis-Dihydrodiols... 

Indigo is very stable to light and heat. The molecule does not readily undergo electrophilic or nucleophilic substitution. However, it can be successfully sulfo-nated in concentrated sulfuric acid to give the tetrasulfonic acid, and halogenated in nitrobenzene to introduce up to six halogen atoms. 

Between 1890 and 1904, there was a significant improvement in sales of BASF products to Asia, which until then had accounted for only four percent of turnover. The surge was mainly due to the fact that large quantities of synthetic indigo were being purchased as a substitute for the inferior natural product. Performance in China mirrored that of Japan, and each country accounted for around seven percent of BASF s total worldwide turnover by 1904 (Abelshauser, W. et al.). 

This is an amino acid the name of which does not have the ine termination. The beta carbon group in alanine has substituted in it the complex group, (CsHeN), which Is known as the indol radical. Indol is a benzene derivative related to indigo. Tryptophane derives its name... 

Phenyl Glycine ortho-Carboxylic Acid.—The next step toward indigo is the formation of phenyl glycine ortho-carbo3grlic acid which is an ortho-dimino derivative of a mixed ring-carboxy and side-chain-carboxy acid. With chlor acetic acid anthranilic acid forms an amino acetic acid derivative in which anthranilic acid, acting as ammonia or an amine, is substituted in acetic acid. 

This compound may be termed anthranilo acetic acid, but as it is also a phenyl substituted glycine or amino acetic acid it is termed phenyl glycine ortho-carboxylic acid. The rest of the synthesis of indigo will be discussed under indigo itself, but as it all involves the original synthesis of anthranilic acid from a cheap raw material and as the phenyl glycine or//fo-carboxylic acid is an amino aromatic acid, this much has been given here. 

This technique was adapted to thin layer chromatography by Acker-mann (43), The substrates used were 1-naphthylacetate, 2-azobenzene-l-naphthylacetate, and indoxylacetate. Sensitivity was in the nanogram range. A later study (44) was carried out using different activation techniques in an attempt to make the procedure more sensitive. Mendoza et al, (45) used indoxyl and substituted indoxyl and naphthyl acetates as substrates. Indigo compounds produced by the hydrolysis of these... 

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