Arsanilic acids

To 1035 g. of syrupy arsenic acid (80-85 Per cent, sp. gr. 2.00/200 Note 1) in a 12-inch evaporating dish, is added 828 g. (800 cc.) of aniline (Note 2) in 100-cc. portions meanwhile, the lumps of aniline arsenate which are formed are broken up by rapid stirring with a porcelain spatula. When all the aniline has been added, the powdered solid is transferred to a 3-I. round-bottom flask equipped with a mechanical stirrer, a thermometer reaching to the lower part of the vessel, and a condenser arranged for downward distillation (Note 3) an additional 800 cc. of aniline is added and the flask slowly heated in an oil bath. The bath may be kept at a temperature not exceeding 170-175° as long as there is any considerable amount of unmelted material in the flask. When the contents of the flask have become liquid the temperature of the bath is dropped and the mixture held at 155-160° (inside temperature), with continual stirring, for at least four and a half hours. The mass will have assumed an intense violet color. 

The reaction mixture is poured into 700 cc. of water and the flask is washed out with a portion of a previously prepared solution of 330 g. of sodium hydroxide in 1400 cc. of water, the washings being added to the reaction mixture. The remainder of the alkali is then added and the mixture agitated and cooled under the tap. At this point, two distinct layers are present, a lower pink-colored alkaline water layer, and an upper strongly 

The arsanilic acid can be obtained from the aqueous alkaline solution either as the free acid or as the sodium salt. To obtain the free acid the solution is acidified with concentrated hydrochloric acid until the purple color of tetrabromophenolsulfon-phthalein is changed to a faint yellow. Care should be taken, in the addition of the acid, not to overstep the end-point (Note 4). Crystallization is stimulated by scratching and the flask is allowed to stand over night to complete the precipitation. The crystals are filtered off and recrystallized once from water (about 2500 cc.) in order to obtain a white product. If the initial crystals obtained have an appreciable pink tinge, it is advisable to remove most of the color by digesting with a small volume of warm alcohol before crystallization from water is attempted (Note 5). 

The yield of purified arsanilic acid obtained according to the above directions amounts to 250-300 g. (Note 6). 

Arsenic acid obtained by oxidizing arsenious oxide with nitric acid is satisfactory a syrupy acid of 80-85 Per cent purity can be obtained on the market. 

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Food efficiency/growth promotion in chicken, turkey, swine arsanilic acid... 

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). 

Arsonic and arsinic acids have found a number of industrial uses. They have been used as corrosion inhibitors for iron and steel, additives to motor fuel, agricultural bactericides, herbicides, and fungicides. 3-Nitro-4-hydroxyphenylarsonic acid (roxarsone) [121 -19-7] C H AsNOg, has found widespread use as an additive to poultry feed for the control of coccidiosis and other poultry diseases (122,123). Arsanilic acid [98-50-0] C HgAsNO, has also been used for this purpose (124) and for growth promotion in swine. It is manufactured and suppHed by Duphar Nutrition Co., Inc., Fleming Laboratories, Inc., Dr. Mayfield Laboratories, Inc., and Whitmoyer Laboratories, Inc. 4-Nitrophenylarsonic acid [98-72-6] C H AsNO and... 

V-Acetyl-4-hydroxy-m-arsanilic acid [97-44-9] from water. 

To a solution of 130 g. (0.6 mole) of arsanilic acid (Org. Syn. 3, 13) in 600 cc. (0.6 mole) of normal sodium hydroxide is added 52 g. (0.62 mole) of sodium bicarbonate and 70 g. (0.75 mole) of chloroacetamide (Org. Syn. 7, 16). The mixture is heated 011 a water bath to 90-1000 and a steady evolution of carbon dioxide occurs. At the end of two hours, when gas evolution has practically ceased, the mixture is cooled to 40° C., stirred vigorously and 150 cc. of 1 1 hydrochloric acid poured in rapidly. /i-Arsonophenylglycinamide crystallizes at once and, after cooling to room temperature, is filtered by suction and washed once with 2 per cent hydrochloric acid (Note 1), then with cold water. The crude product thus obtained is contaminated with some arsanilic acid and possibly other products. These are removed during purification. The crude product is suspended in about 400 cc. of water and with vigorous stirring, treated carefully with 25 per cent aqueous sodium hydroxide until solution is just complete. At this point the mixture is still acid to litmus and an excess of sodium hydroxide is to be avoided to prevent decomposition of the product. About 15 g. of boneblack... 

From this filtrate approximately 15-30 g. of arsanilic acid may be recovered by just neutralizing to Congo Red with sodium hydroxide... 

Z-Arginine hydrochloride, 12, 4 Arsanilic acid, 16, 85 Arsonoacetic acid, 10,108 Arylarsonic acid, preparation, IS, 59 y-Arylbutyric esters, 18, 25 Arylsulfur chlorides, preparation, 15, 45... 

ABA-l-GAT Arsanilic acid conjugated with the synthetic polypeptide l-GAT AC Adenylate cyclase ACAT Acyl-co-enzyme-A acyltransferase... 

Anisamide, m54 Anisic acids, m57, m58, m59 Anidisines, m48, m49, m50 Anisole, m55 p-Anisoyl chloride, m60 p-Anisyl alcohol, m61 Anthranilamide, all2 Anthranilic acid, all8 Araboascorbic acid, i61 APDC, p282 Arsanilic acids, all3... 

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) ... 

Arsanilic acid Fed diets containing 45 mg/kg for 9 weeks no effect except slightly elevated liver content of 1.2 mg/kg fresh weight. At dietary levels of 455 mg/kg, liver residues were 6.4 mg/kg FW after 9 weeks no other effects evident 5... 

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... 

Turkey, Meleagris gallopavo Arsanilic acid in diet Maximum dietary concentration for turkeys less than 28 days old is 300-400 mg/kg feed (NAS 1977)... 

Phenylarsonic feed additives for disease control and improvement of weight gain in domestic poultry safe dietary levels Maximum levels in diets, in mg/kg feed, are 50-100 for arsanilic acid, 25-188 for 3-nitro-4-hydroxy-phenylarsonic acid (for chickens and turkeys, not recommended for ducks and geese), and 180-370 for others (NAS 1977)... 

For the reduction of nitro-compounds containing a group which may be attacked by nascent hydrogen, as, for example, an aldehyde group, an unsaturated side chain, and so on, special methods must he applied. In such cases ferrous hydroxide or iron powder (cf. Chap. VII. 5, arsanilic acid) are often used. The reduction is carried out thus a weighed amount of ferrous sulphate is caused to act, in the presence of alkali (potassium or sodium hydroxide, baryta), on the substance to he reduced. In this way it is possible to reduce, for example, o-nitro-benzaldehyde to aminobenzaldehyde, and o-nitrocinnamic acid to amino-cinnamic acid. 

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

If the p-hydroxy-compound, obtained by boiling diazotised arsanilic acid with water, is nitrated, and the nitro-group so introduced is reduced to the amino-group, further reduction yields the corresponding arseno-compound, salvarsan. (Formulate these reactions )... 

Turkey, Meleagris gallopavo Arsanilic acid in diet... 

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