4-Arylamino

Typical auxochromes are hydroxyl, alkoxyl and aroxyl, amino, alkyl-amino and arylamino, all of which promote conjugation with lone pairs on oxygen or nitrogen atoms. 

Anilino-4-arylthiazoles (211) are mercurated on the phenyl ring (Scheme 133) (453. 454). The phenyl ring is also the site of mercuration in 2-arylamino-4-(2-thienyl)thiazoles (213) (Scheme 134) (455). 

The high reactivity of the 5-position in 1.3-selenazoles toward electrophilic substitution was also observed on azocoupling. By reacting molar quantities of an aqueous solution of a diazonium salt with an ethanolic solution of a 2-arylamino selenazole. for example, the corresponding 2-arylamino-5 azoselenazoles are formed in a smooth reaction (100). They deposit from the deeply colored solution and form intenselv red-colored compounds after their recrystallization from a suitable solvent (Scheme 36l. 

Treatment of 2-(arylamino)selenazoles with sodium nitrite in glacial acetic acid at room temperature gives the corresponding nitroso compounds instantaneously (Scheme 381 (29). These compounds give rise to... 

N-nitrosamino derivatives are only obtained when the 5-position is blocked, for example, with 2-arylamino-4.5-diphenylselenazole or 2-arylamino-.S-phenylselenazole (Scheme 41). Differents compounds have been prepared (Table X-8i (29). 

Diazotization of 2-arylamino-4-phenylselenazoles with phenyldiazon-ium chloride gives 2-arvlamino-4-phenvi-5-phenvlazoselenazo es (Scheme 42) (29). 

Such is the case of 2-amino or 2-(monoalkyl or arylamino)-4-oxo-selenazolines. Thus because of this aminoc=iimino tautomerism. these compounds can be called 2-aminose enazo ines or 2-iminoselenazolidines and can be classed either as selenazolines or selenazolidines. This has been a source of controversy that has been resolved by recent spectroscopic studies (67. 68). 

Arylamino-2-chloroprop-2- enoic esters (72) obtained from 2-chloroaceto acetic ester (71) and arylamines, react with thiourea to yidd substituted 2-aminothiazoles (73), probably by initial nucleophilic substitution of the chloro atom of 72, followed by cyclization with loss of aniline (Scheme 33) (729). 

Arylamino thiazoles unsubstituted in the 4- or 5-position were obtained from Q ,P-dihalogenoethers and arylthioureas (8, 23, 147). 

Some 2-arylamino arsenic derivatives of thiazole have been also prepared (598) (Table 11-18). 

Biomedical Applications. In the area of biomedical polymers and materials, two types of appHcations have been envisioned and explored. The first is the use of polyphosphazenes as bioinert materials for implantation in the body either as housing for medical devices or as stmctural materials for heart valves, artificial blood vessels, and catheters. A number of fluoroalkoxy-, aryloxy-, and arylamino-substituted polyphosphazenes have been tested by actual implantation ia rats and found to generate Httle tissue response (18). 

The cyclization of 5-(2-carboxyanilino)pyrimidine (170) with sulfuric acid/phosphoric acid leads to the 7-chloropyrimido[5,4-A]quinolinetriones (171) (57JCS4997, 74KGS131), the 2,4,10-trichloro compounds being obtained with phosphoryl chloride (72JHC91), whilst a formally similar cyclization of 4(6)-arylamino-5-ethoxycarbonylpyrimidines gives... 

Oxidative procedures have been utilized for the synthesis of both monocyclic five-membered heterocycles and their ring-fused analogs, although the ease of synthesis of the precursors for the latter ring closures results in wider application of this procedure. A variety of oxidizing agents have been used and the conversion of the benzylidene hydrazidines (221) into the 4-arylamino-l,2,4-triazole (222) was effected with mercury(II) oxide (77BCJ953). 

Benzothiazole, 2-amino-6-thiocyanato-azo dyes from, 1, 328 Benzothiazole, 2-aryl-synthesis, 6, 321 Benzothiazole, 2-arylamino-synthesis, 6, 323 Benzothiazole, 2-aryloxy-Fries rearrangement, 6, 289 Benzothiazole, 2-benzyl-picrate, 6, 252 Benzothiazole, 2-chloro-dyes from, 1, 321-322 synthesis, 6, 323 Benzothiazole, 2,3-dihydro-oxidation, 6, 272 Benzothiazole, 2-dimethylamino-synthesis, 5, 128... 

Furoxans, aroylamino-synthesis, 6, 414 Furoxans, aryl-reactions, 6, 412 Furoxans, arylamino-synthesis, 6, 414 Furoxans, arylaminobutyl-synthesis, 6, 423... 

Imidazolidin-2-one, l-(5-nitro-2-thiazolyl)-pharmacological activity, 6, 328 Imidazolidin-4-one, l-aryl-3-phenyl-2-thioxo- C NM S, 355 Imidazolidinones C NMR, 5, 355 Imidazolidin-2-ones nucleophilic displacement, 5, 428 polymers, 1, 279-280 reactivity, 5, 376 synthesis, 5, 466, 471 Imidazolidin-4-ones synthesis, 5, 468 Imidazoline, 2-alkyl-synthesis, 5, 463 Imidazoline, 2-amino-applications, 5, 498 Imidazoline, 2-aryl-synthesis, 5, 463 Imidazoline, 2-methyl-synthesis, 5, 487 Imidazoline, 2-nitroamino-synthesis, 5, 471 2-Imidazoline, 2-arylamino-tautomerism, 5, 368 2-Imidazoline, 1-benzyl-methylation, 5, 425 2-Imidazoline, 1,2-diaryl-synthesis, 5, 463... 

Theophylline, 9-aryl-synthesis, 5, 576 Theophylline, 8-arylamino-synthesis, 5, 576 Theophylline, 9-benzyl-rearrangement, 5, 534 Theophylline, 8-chloro-reduction, 5, 541 Theophylline, 6-deoxy-reduction, 5, 541 Theophylline, 8-dimethylamino-synthesis, 5, 580 Theophylline, 8-methyl-synthesis, 5, 591 Theophylline, 8-methylthio-synthesis, 5, 578 Theophylline, 8-nitro-synthesis, 5, 538 Theophylline, 7-phenyl-synthesis, 5, 581 Theophylline, 8-phenyl-7-oxide... 

Thiatriazole, 5-arylamino-alkylation, 6, 596 anticancer activity, 6, 598 methylation, 6, 590 reactions... 

Thiazoline, trans-2-amino-4,5-dimethyl-synthesis, 6, 310 2-Thiazoline, 2-aryl-synthesis, 6, 307, 308, 309 2-Thiazoline, 2-arylamino-tautomerism, 6, 248 2-Thiazoline, 2-dialkylamino-synthesis, 6, 308 2-liiiazoline, 5-imino-synthesis, 5, 461 2-"niiazoline, 2-mercapto-hydrolysis, 6, 272 oxidation, 6, 272 synthesis, 6, 307 2-Thiazoline, 2-methyl-aldehyde synthesis from, 1, 469 2-Thiazoline, 2-methyl-acetylation, 6, 270 acylation, 6, 270 H NMR, 6, 243... 

Thiophene, 2-amino-3-cyano-5-phenyl-synthesis, 4, 888-889 Thiophene, 3-amino-4,5-dihydro-cycloaddition reactions, 4, 848 Thiophene, 2-amino-3-ethoxycarbonyl-ring opening, 4, 73 Thiophene, 2-amino-5-methyl-synthesis, 4, 73 Thiophene, 2-anilino-synthesis, 4, 923-924 Thiophene, aryl-synthesis, 4, 836, 914-916 Thiophene, 2-(arylamino)-3-nitro-synthesis, 4, 892 Thiophene, azido-nitrenes, 4, 818-820 reactions, 4, 818-820 thermal fragmentation, 4, 819-820 Thiophene, 3-azido-4-formyl-reactions... 

The synthesis of 5-aminothiazoles via the reaction of isocyanate derivatives with aminomalononitrile p-toluenesulfonate (AMNT) has been investigated. It was found that AMNT 12 reacted with alkyl and aryl isothiocyanates in l-methyl-2-pyrrolidine (NMP) to furnish 5-amino-2-(alkylamino)-4-cyanothiazoles (13a) and 5-amino-2-(arylamino)-4-cyanothiazoles (13b-c) in 44-81 % yields. " ... 

Thiophenealdehyde has been used in the reductive alkylation of 2-aminopyridine and 2-aminopyrimidine. 2-Arylamino-4- (2-thienyl )thiazoles have been prepared by the reaction of 2-acetylthio-phene with A-arylthioureas in the presence of iodine, ... 

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