3,492,300 United States Patent Office Patented Jan. 27, 1970 2 3,492,300 reaction is conducted with sodium nitrite in dimethyl BENZOI5,6-1,2,3ITRAZINO(3,4-b)NIDAZOLESAND SYNTHESIS THEREOF formamide acidified with hydrochloric acid. Stanley C. Bell, Narberth, and Scott J. Childress, Philar When the action is complete, the precipitated product delphia, Pa., assignors to American Home Products (II) is separated by conventional methods, such as, filtra Corporation, New York, N.Y., a corporation of tion, and then recrystallized from a suitable solvent e.g. Delaware an alkanol, dimethylsulfoxide and dioxan to afford an ap No Drawing. Continuation-in-part of application Ser. No. propriate benzotriazinoindazole (II). 614,810, Feb. 9, 1967. This application Apr. 5, 1968, The 3-phenylindazoles (I) used as starting materials Ser. No. 719,236 to Synthesize the compounds of the present invention are int, CI, C07d 57/34 O prepared by the procedure described in copending U.S. U.S. Cl. 260-248 10 Claims patent application, Ser. No. 610,471, entitled “Indiazole 5-Sulfonamides," filed on Jan. 20, 1967 by Stanley C. Bell and Carl Gochman. The nitrites used in the process ABSTRACT OF THE DISCLOSURE of the present invention are known compounds which By reacting 3-phenylindazoles with nitrites, there are 5 may be readily obtained from commercial sources. By the formed benzo (5,6,1,2,3 triazino (3,4-b)indazoles which term "reaction-inert, water miscible solvent' is meant any are useful as anti-amebic agents. solvent which will easily admix with water and dissolve the reactants without interfering with their interaction. Typical examples of such solvents are: water, an alkanol, This is a continuation-in-part application of U.S. pat 20 dioxan and dimethoxy ethane. By “mineral acid' as ent application, Ser. No. 614,810, filed on Feb. 9, 1967, employed herein is meant any inorganic acid, such as, now abandoned, and also entitled "Synthesis of Benzo hydrochloric, hyrobromic, and sulfuric acid. Many such 5,61,2,3 Triazino(3,4-b) Indazolines.” “mineral acids' and "reaction-inert, water miscible solv This invention relates to new and novel benzotriazino ents' will readily suggest themselves to one skilled in the indazoles as well as to a method for their preparation. 25 art of chemistry. The word "nitrite” as employed herein In particular, this invention is concerned with benzo[5, refers to both inorganic and organic nitrite compounds 6 1,2,3 triazino (3,4-b)indazoles which in standard and e.g. sodium nitrite, potassium nitrite, ethyl nitrite, propyl accepted tests have demonstrated utility as anti-amebic nitrite and butyl nitrite etc. agents. In accord with the present invention, the benzotriazino The compounds which are included within the scope 30 indazoles (II) of this invention have been found to of this invention are depicted by the following formula: possess valuable anti-amebic properties. In particular, in standard in vitro screening procedures these compounds Ns have demonstrated anti-amebic activity, especially against R N Endameba histolytica and are useful as anti-amebic R N 35 agents. N/N/ In the amebicidal evaluation of the compounds of this invention the test Substance is incorporated and diluted (). in the aqueous phase of Boeck-Drbohlav diphasic medium fortified with rice starch. The medium is inoculated with 40 polybacteria and a known number of trophozoites of E. histolytica NIH 200. After forty-eight hours incubation t at 35 C., the trophozoites are counted. The procedure is wherein R and R are selected from the group consist derived from Thompson, et al, Antibio. and Chemo., 6, ing of hydrogen, halogen, lower alkyl, and lower alkoxyl; 337-50 (1956). The endpoint is expressed as the percent and R and R4 are selected from the group consisting of E. histolytica killed at a particular concentration (ug./ of hydrogen, sulfamoyl, halogen, lower alkyl and lower ml.) of test compound. In this test the benzo 5,6] 1,2,3] alkoxy with the proviso that when Rs is sulfanoyl R4 is triazino (3,4-b)indazoles of this invention average about selected from the group consisting of hydrogen, halogen, a sixty-five percent kill of E. histolytica at a concentration lower alkyl and lower alkoxy. Typical examples thereof of 500 ug./ml. and about a ninety percent kill of E. are: 2 - chlorobenzo[5,6] (1,2,3 triazino (3,4 - b)inda 50 histolytica at 1000 ug./ml. zole-11-sulfonamide; 3-bromobenzo[5,6] 1,2,3ltriazino The anti-amebic activity of the compounds (III) of (3,4-b)indazole-11-sulfonamide and 10-bromo-2-methoxy this invention can be utilized for washing equipment in benzol 5,61,2,3 triazino (3,4-b)indazole. hospitals and homes, instruments used in medicine and The new and novel process of this invention is illus bacteriology, clothing used in bacteriological laboratories, trated by the following reaction scheme: and floors, walls and ceiling in rooms in which a back NH N/NS ground free of E. histolytica is desired. R1-- R N The benzotriazinoindazoles (II) of the present inven R-H R N tion are useful in a number of compositions comprising YC-NH \ the active compound and an inert material. In such com 60 positions, while the active compounds (II) of this inven N - tion may be employed in concentrations as low as 500 Ž / p.p.m., from a practical point of view, it is desirable to use Ra-l R from about 0.10% by weight, to about 5% by weight or R R more. In particular, useful compositions for use as wash 65 ing solutions, the active compounds of this invention may (I) (II) bybe weight.used generally in the range of from 0.050% to 0.25% wherein R. R. R. and R are defined as above. The re The benzo.5,6] 1,2,3) triazino(3,4-b)indazoles of the action is effected by admixing a nitrite with a solution present invention can readily be formulated by those of a 3-phenylindazole (I) in a reaction-inert, water misci 70 skilled in the art into a wide variety of amebicidal com ble solvent acidified with a mineral acid. Preferably this positions. The examples hereinafter will provide details 3,492,300 3 4 for doing so in representative instances. However, in EXAMPLE V general, standard techniques can be employed. For exam An amebicidally active wash solution is prepared as ple, the active compounds per se can be made up in stock follows: solutions. They can also be formulated as suspensions in Components: Parts by wt. an aqueous vehicle. These make useful mixtures to de Potassium tripolyphosphate --------------- 19.5 contaminate premises. Also, aqueous vehicles containing Sodium tripolyphosphate ------------------ 5.0 emulsifying agents, such as sodium lauryl Sulfate, and Alkyl aryl Sulfonate anionic detergent ------ 33.0 relatively high concentrations, e.g., up to about 5% by Lauric acid alkanolamine condensate ------ 5.0 weight, of a benzotriazinoindazole (II) can be formulated Carboxymethylcellulose ------------------- 0.5 by conventional techniques. O The following examples are given by way of illus 2 - chlorobenzo 5,61,2,3 triazino (3,4 - b) tration and are not to be construed as limitations of indazole - 11 - Sulfonamide ------------ 1.0 this invention, many variations of which are possible The above components are mixed together at 22 C. to without departing from the scope and spirit thereof. form the final product. 5 EXAMPLE I EXAMPLE VI To a solution of 1.7 g. of 3-(2-amino-5-chlorophenyl)- An amebicidally-active industrial cleaning composition 5 - sulfamoyl-1H-indazole in 40 ml. of dimethylforma is prepared as follows: mide acidified with dilute hydrochloric acid, there is Components: Parts by wt. added an aqueous solution of sodium nitrite. The result 20 Neutral soap (K and Na soaps of stearic, pal ing yellow precipitate is then collected, washed with eth mitic and oleic acid) ------------------ 30.0 anol, and recrystallized from dimethylformamide-water Bentonite ------------------------------- 30.0 to afford 2 - chlorobenzo 5,61,2,3 triazino (3,4 - b) Sodium lauryl Sulfate -------------------- 10.0 indazole - 11 -sulfonamide. Lanolin --------------------------------- 5.0 Analysis.--Calcd. for CHCINO2S: C, 46.78; H, 25 3 - bromobenzo 5,61,2,3} triazino (3,4 - b) 2.42; N, 20.99; S, 9.61; C1, 10.62. Found: C, 46.95; H, indazole - 11 - sulfonamide ------------ 1.5 2.60; N, 20.89 S, 9.6 C1, 10.5. The bentonite and sodium lauryl sulfate are mixed to EXAMPLE II gether. The soap and lanolin are mixed with the sulfon 30 amide and heated to about 70° C., after which they are To a solution of 3.5 g. of 3-(2-amino-4-bromophenyl)- mixed with the bentonite and sodium lauryl sulfate. The 5 - sulfamoyl-1H-indazole in 80 ml. of wated acidified product may then be pressed into cake form, or 27 parts with dilute sulfuric acid, there is added an aqueous solu of corn meal may be mixed with 75 parts of the mitxure tion of butyl nitrite. The resulting precipitate is then col to form a powdered amebicidally-active soap composi lected, washed with methanol, and recrystallized from di tion. methylsulfoxide to afford 3-bromobenzo 6.5) (1,2,3 tri EXAMPLE VII azino(3,4-b)indazole-11-sulfonamide. A biocidally-active composition useful to decontami In a similar manner, 3 - (2 - amino-5-methyl)-6- nate premises which have been infected with E. histoly chloro-5-sulfamoyl-1H-indazole is reacted with ethyl ni tica is prepared by dissolving 2-chlorobenzo 5,61,2,3] trite to yield 10 - chloro - 2 - methylbenzo 5,6] 1,2,3] 40 triazino - (3,4 - b)indazole - 11 - sulfonamide in meth triazino (3,4-b)indazole-11-sulfonamide.