Phenol 2,4-diiodo

Desulfitobacterium chlororespirans can use ortho-substituted phenols as electron acceptors for anaerobic growth, and is able to debrominate 2,6-dibromo-4-cyanophenol (Bromoxynil) and 2,6-dibromo-4-carboxyphenol. In contrast, 2,6-diiodo-4-cyanophenol (loxynil) was deiodinated only in the presence of 3-chloro-4-hydroxybenzoate (Cupples et al. 2005). 

Several compounds can be oxidized by peroxidases by a free radical mechanism. Among various substrates of peroxidases, L-tyrosine attracts a great interest as an important phenolic compound containing at 100 200 pmol 1 1 in plasma and cells, which can be involved in lipid and protein oxidation. In 1980, Ralston and Dunford [187] have shown that HRP Compound II oxidizes L-tyrosine and 3,5-diiodo-L-tyrosine with pH-dependent reaction rates. Ohtaki et al. [188] measured the rate constants for the reactions of hog thyroid peroxidase Compounds I and II with L-tyrosine (Table 22.1) and showed that Compound I was reduced directly to ferric enzyme. Thus, in this case the reaction of Compound I with L-tyrosine proceeds by two-electron mechanism. In subsequent work these authors have shown [189] that at physiological pH TPO catalyzed the two-electron oxidation not only L-tyrosine but also D-tyrosine, A -acetyltyrosinamide, and monoiodotyrosine, whereas diiodotyrosine was oxidized by a one-electron mechanism. 

Sato and coworkers fonnd that site-selective iodine-magnesinm exchange reactions of 1,4-diiodo-l,3-alkadienes were attained only by nsing the organomagnesinm ate complex, lithium dibutylisopropyhnagnesate (Scheme 9). The magnesiated iodoalkadienes were transformed into polysnbstitnted styrenes and phenols. 

Novel phenanthro[9,1 ()-r/ isoxazoles 37 have been prepared by intramolecular Stille-Kelly stannylation/coupling of o,o -diiodo-4,5-diarylisoxazoles and by PIFA-mediated non-phenolic oxidative coupling of the corresponding non-halogenated substrates <02T3021>. 

Reaction of one equivalent of diiodo acyclic link molecule 7 with one equivalent of 2,9-di(p-phenol)-l,10-phenanthroline 5 under high-dilution conditions in the presence of a large excess of caesium carbonate affords the chelating macrocyle 8 in 45% yield (Scheme 9.6). 

Cyanophenol, which is first transferee into 4-cyano-2,6-diiodo-phenol, can be photolysed with benzene to give 4-cyano-2,6-diphenylphenol in 71 % yield 58). The latter is identical with the compound prepared from 2,6-diphenyl-4-nitrophenol59). 

The important phenols that have shown marked activity against roundworms are hexylresorcinol (9), 2,4,5-trichlorophenol (10), 2,6-diiodo-4-nitrophenol (disophe-nol, 11), thymol (12), iodothymol (13) and 4-cyano-2-iodo-6-nitrophenol (nitro xynil,14) and butyphen (15). Of these disophenol (11) and nitroxynil (14) are commonly used as veterinary anthelmintics [11,23]. 

To 1 2M diethylzinc in toluene which had first been added to a solution of diiodo methane in toluene at 0°, a solution of phenol in toluene was introduced. After 10 secs, the mixture was stirred at 0° for 5 min and refluxed for 1.5 h to give 2-methylphenol. CHjIj + EljZn —> ElZnCHjI... 

By contrast, 2,6-dik)do-4-nitromethoxybenzene in ethanol solution underwent displacement of the methoxy group by dropwise treatment at OX with excess isopropylamine followed by completion of reaction at ambient temperature during 2 hours to afford, in 70% yield, N-isopropyl 2,6-diiodo-4-nitroaniline. Secondary amines resulted simply in dealkylation to give the corresponding phenol (ref.57), a difference probably due to the influence of a differing degree of steric hindrance. 

Diiodo phenol monosulfonic acid—CtHjIjjOHjSOsH—is used as an antiseptic and astringent, in the form of its salts under the name sozoiodol and Diiodo resorcin monosulfonic acid — C HIa,(0H)s(i..s),S03H —is also used as an antiseptic having but slight poisonous qualities, under the name picrol. 

The key step in this approach is the formation of the precatenate 1 from the diphenolic derivative of 1,10-diphenylphenanthroline in presence of Cu(I). It can be seen that in structure l,the four phenol groups are in good position for subsequent attack and hence cyclization by the diiodo compound giving the catenate 2 (Fig. 21b). The Cu(I) ion can be easily removed by treatment with potassium cyanide, affording the catenane. The tridimensional template effect induced by Cu(I) was extended to the formation of a trefoil knot (Fig. 21c,d). 

Other Names lodophenol blue Phenol, 4,4 -(3H-2,l-benzoxathiol-3-ylidene) /5 [2,6-diiodo-, S,S-dioxide 3H-2,l-Benzoxathiole, phenol deriv. NSC 36792, Tetraiodophenolsulfonephihalein CA Index Name Phenol, 4,4 -(l,l-dioxido-3H-2,l-benzoxathiol-3-ylidene)W5 [2,6-diiodo-CAS R istry Number 4430-24-4 Merck Index Number Not listed Chemical Structure... 

The first step in the assumed reaction is the oxidation of the diiodo-phenolate ion by removal of one electron from the oxygen atom, leading to the free radical I oxidation of another diiodotyrosine molecule by removal of one electron in the para-position of the diiodophenolic groups leads to a second free radical II. Addition of I and II would lead to the phenoxydienone postulated as being the intermediate formed. 

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