Arsanilic acid Arsenates

Arsanilic acid (arsenic) Swine, chicken, and turkey 500... 

Chemically synthesized antimicrobials used in animal and poultry feeds include arsenicals, eg, arsanilic acid [98-50-0] sodium arsanilate [127-85-5] and roxarsone [121-19-7]-, sulfa dmgs, eg, sulfadimethoxine [122-11-2], sulfamethazine [57-68-1], and sulfathiazole [72-14-0]-, carbadox [6804-07-5]-, and nitrofurans, eg, furazoHdone [67 5-8] and nitrofurazone [59-87-0] (see Antibacterial agents, synthetic Antiparasitic agents). 

Chickens rapidly excrete arsenicals only 2% of dietary sodium arsenite remained after 60 h (NAS 1977), and arsanilic acid was excreted largely unchanged (Woolson 1975). Excretion of arsanilic acid by chickens was affected by uptake route excretion was more rapid if administration was by intramuscular injection than if it was oral (NRCC 1978). Studies with inorganic As+5 and chickens indicated that (Fullmer and Wasserman 1986) ... 

Various phenylarsonic acids — especially arsanilic acid, sodium arsanilate, and 3-nitro-4-hydroxyphenylarsonic acid—have been used as feed additives for disease control and for improvement of weight gain in swine and poultry for almost 40 years (NAS 1977). The arsenic is present as As+5... 

Arsanilic acid was first synthesised, in very poor yield, by melting arsenic acid with aniline ... 

Arsanilic acid was prepared by Bechamp 1 by heating aniline arsenate to 190-200°. The product was originally described as the anilide of arsenic acid, but Ehrlich and Bertheim 2 showed its structure to be that of a true aryl arsenic acid. 

The feasible methods of preparing arsanilic acid all depend upon the interaction between aniline and arsenic acid. Various temperatures ranging from 150 to 200° and various ratios of aniline to arsenic acid have been recommended.3... 

Arsanilic acid see Arsenic and arsenic compounds) Arsenic and arsenic compounds... 

Certain organic arsenicals are incorporated in pig and broiler feeds to improve weight gain and feed efficiency and to combat enteric infections. Arsanilic acid... 

Anthranilic acid, 2, 47 7, 31, 32, 33 Anti-foam agents, 7, 33 Antimony trichloride, 7, 80 Arsanilic Acid, 3,13 Arsenation, (see Arsonation)... 

The pH of the filtrate was lowered to 4.5 by the addition of 0.2 mole of hydrochloric acid, and an additional 5.0 g of by-products, the composition of which was not determined, was filtered off. The filtrate was then brought to a pH of 3.2 by addition of 0.6 mole of hydrochloric acid, and 128.0 g (29.5% based upon arsenic acid) of arsanilic acid were recovered as a precipitate. 

The arsanilic acid filtrate was combined with the by-products filtered off during each of the three filtration steps. 2.8 mol of hydrochloric acid were added to the combined arsanilic acid filtrate and the mixture was heated at 80°C for 5 days. Arsanilic acid was then precipitated from the remaining hydrolyzed mixture in the manner described for the primary reaction product, and an additional 120.0 g (27.5% based on arsenic acid) were recovered. The filtrate contained 14.0 g (3.2%) of arsanilic acid which could be recovered at least partially in subsequent processing. Thus it can be seen from this example that an arsanilic acid yield of 59% was obtained. 

Acetyl-p-arsanilic acid may be prepared by the usual methods of acetylation, or by diazotising -aminoacetanilide and introducing the arsenic residue in the usual way. It forms glistening, white plates from water, soluble in sodium carbonate solution, sparingly soluble in dilute hydrochloric acid. Its sodium salt commercially goes under the names of Arsacetin and Acetylatoa yl. This salt crystallises from methyl alcohol in needles, and occurs associated with 3 to 6 molecules of water of crystallisation. OMminoacetyl-p-arsanilic acid is also known. ... 

The isolation of these compounds is based on the fact that ethylene chlorohydrin under suitable conditions can be condensed with aromatic amines to give arylamino-alcohols. Although condensation has been accomplished using p-arsanilic acid as the amine, negative results are obtained when the amino-group is in the meta position with respect to the arsenic, as in the case of w-arsanilic acid, 3-amino-4-methylphenyl-arsinic acid, and 8-amino-4-hydroxyphenylarsinic acid. 

Probably the most frequently used method of digestion incorporates the use of nitric and sulphuric acids. Kopp and Bandemar used this method and experienced 91 to 114% recovery of arsenic trioxide added to de-ionized water and 86 to 100% recovery of the compound added to river water. Evens and Bandemar recovered 87% of the arsenic trioxide added to eggs. By modifying the method by the addition of perchloric acid, and Caldwell and coworkers observed 80 to 90% arsenic recovery with o-nitrobenzene-arsonic acid, 85 to 94% with o-arsanilic acid and 76.7% with disodium methylarsenate. 

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