US3093541A - Bis quaternary oximes - Google Patents

Description

United States Patent 1 Claim. (Cl. 167-65) (Granted under Title 35, US. Code (1952.), sec. 266) This invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment to us of any royalty thereon.

This is a division of application Serial No. 809,578, filed April 28, 1959, now Patent No. 3,077,476, granted March 12, 1963.

This invention is directed to certain diquaternary pyridinium halide oximes which are useful as chemotherapeutic and prophylactic agents for mammals poisoned by anticholinesterases, particularly the nerve gas known as GB or sarin, i.e., isopropyl methylphosphonofluoridate.

The invention relates to 1,1'-polymethylene bis(4- formylpyridinium) halide dioximes wherein the polymethylene group contains from 2 to 6 carbon atoms; These compounds have the structural formula The invention also relates to 1,1'-(2-'butenylene) bis (4-formylpyridinium) halide dioximes of the formula 0 H=N O H GH=N O E (III) The invention further relates to 1,1'-polymethylene bis (3-formylpyridinium) halide dioximes of the formula wherein R is a polymethylene group containing from 2 to 6 carbon atoms.

Another class of compounds included are the 1,1-(pphenylenedimethylene) bis (3-formy1pridinium) halide Patented June 11, 1963 dioximes of the formula i CH==NOH (IVb) This invention further relates to unsymmetrical bisquaternary 4-formylpyridinium halide monoximes of the formula 0 This invention also relates to the compounds This invention also relates to the compounds CH=NOH (VIII) While all these compounds are useful in varying degree for the purposes set out above, the difierent groups exhibit quite striking differences in effectiveness. In all the above formulas X is chloride, bromide or iodide, which appear to be equivalents as to physiological action, except for their effect on solubility.

Wilson et -al., in Patent No. 2,816,113, granted December 10, 1957, disclose a group of compounds which are effective as antidotes for treatment of mammals poisoned by compounds of high anticholinesterase activity, such as the nerve gases diisopropylphosphorofluoridate (DFP), isopropyl methylphosphonofluoridate (GB), and O-ethyl, N,N dimethyl phosphoroamidocyanidate (GA), as well as other related organic phosphorus compounds, including many insecticides. The compound of the Wilson et al. group which has received by far the most attention is 2-formyl-l-methyl pyridinium iodide oxime, commonly known as Z-pyridine aldoXime methiodide or 2-PAM. This compound is outstanding in its ability to reactivate, in vitro, oholinesterase which has been inhibited by, for example, GB. Thus, even as compared to the very closely related 4-PAM, disclosed in Example ll of the Wilson patent, 2-PAM shows much greater activity. With isopropyl methylphosphonylated acetylocholinesterase the rate constant at pH 7.4 and 25 C. in the presence of 10- M a'cetylocholine is 2x10 per mole per minute for Z-PAM and 1.4 X10 per mole per minute for 4-PA1M. The Wilson patent shows a' high rate of survival in mice which have been poisoned with paraoxon and then treated witha) present the recommended remedy. Recently, 2-PAM has been reported to enhance considerably the activity of atropine in the chemotherapeusis of poisoning due to organophosphorus compounds.

The compounds of Formula I above in which R contains from 2 to 6 carbon atoms are appreciably more effective than 2-PAM as reactivators of GB-inhibited acetylcholinesterase and also in enhancing the activity of atropine in both therapy and propylaxis. When If is bromide, the variation of the rate constant for the in vitro reactivation of GB inhibited eel acetylcholinesterase at pH 7.4 and 25 C. was found to be as follows:

TABLE 1 R Rate constant (l/molcs/minutes) (cum 7 10 (cum 6x10 HM 6x10 (C M 1x10 (cum 6x10 When administered in combination with atropine to animals poisoned with GB the order of effectiveness was somewhat diiferent. Under these conditions the compound in which R= (CH i.e., 1,1-trin1ethy1ene bis (4- formylphyridinurn) bromide dioxime also known as TMB-4, was most effective. In rats challenged with a 2 LD dose of GB administered intravenously, all of a group of six animals survived if the atropine-TMB-4 combination was administered intravenously immediately after poisoning. The atropine-2PAM combination saved only two of the group of animals. On the other hand, with dogs which were given a 20 LD dose of GB subcutaneously the survival ratios were the same (4/5) for the two treatments, which were given intravenously when symptoms appeared. However, the recovery time was much shorter for the surviving animals which received the TMB-4, i.e., 2 hours, as against 24 hours for those receiving the 2-PAM.

A summary of the reactivation rates and survival ratios for these compounds when administered therapeutically to rats together with atropine is as follows:

TABLE 2 Reactivation rate constant Survival ratio (GB) 7X10 6X10 6X10 1x10 6x10 These compounds constitute our presently preferred group.

Our compounds may be employed prophylactically, i.e., injected before exposure to the anticholinesterase agent, e.g., GB, or therapeutically, i.e., injected subsequent to exposure.

The following series of experiments compares the efiec tiveness of our presently preferred compound, TMB-4,

To minimize absorption effects both the GB and TMB-4 were ordinarily given intravenously. However, in the therapeutic tests on rabbits, dogs and cats, the GB was administered subcutaneously, since death from 20 LD intravenous dose of GB occurs so quickly that it is virtually impossible to give timely administration of. the antidote.

Atropine, when administered, was included in the following amounts.

Mgjkg. Rats 4 Rabbits 2 Dogs and cats 0.5

The prophylactic doses were given within two minutes prior to the injection of the GB, the therapeutic doses so soon as poisoning symptoms were visible.

Table 3 shows the results.

TABLE 3 A. PROPHYLAOTIC The recovery periods, i.e., time for disappearance of sypmtorns of poisoning, among survivors in the above tests, with atropine, were as follows.

TABLE 4 2-PAM TMB-4 Animals Prophylactic Therapeutic Prophylactic Therapeutic The compounds of Formula I in which R contains from 7 to 10 carbon atoms are less effective than those of our preferred group. For these compounds the reactivation rate constant and the survival ratio for rats (measured as given above) were as follows, X- being bromide.

TABLE 5 R Rate Survival ratio (GB) While these compounds were ineffective in vivo against GB, they were, together with 2-PAM, very efiective against certain other anticholinesterases, particularly that designated as VX by the U.S. Army Chemical Corps. All these compounds caused survival of all animals (survival rates of 4/ 4 and 6/6) when administered therapeutically to rats challenged by 2 LD doses of VX.

The compounds of Formula II exhibited properties intermediate those of the two subgroups of Formula I. When X- was chloride the compound had the following properties. (In this and all following tables the survival ratios are those for rats challenged by 2 L13 doses of GB or (VX) and the oxime was employed therapeutically.)

Compounds of Formula III showed reactivation rates very close to those of our preferred group. Thus when X'- in Formula III is bromide the reactivation rate constant was 8 10 as compared to the value for the R =(CH member of our preferred group of 6x10 For the unsaturated member (Formula III) the survival ratio for rats challenged by GB was only 1/ 4 as compared to 6/6 for the saturated analogue (Formula I). Both gave complete survival (ratios of 4/4 and 6/6) for animals challenged by VX, however.

Compounds of Formula IVa showed anomalous properties.

They gave reactivation rates which were low, but survival ratios which were high as compared to Z-PAM, as

shown by Table 6, X- being bromide.

TABLE 6 Survival ratio (GB) Reactivation rate constant a. 5x10 4/4 4. 2x10 3 4 (C 2): HM

TABLE 7 Reactivation rate constant Survival R"EN- ratio (GB) 0,115) iN- 1. 2x10 4/4 The compounds of Formulas VI, VII and VIII, while being of difierent structure are alike in exhibiting reactivation rate constants which are very low as compared to Z-PAM but giving high survival ratios as shown by Table 8, X- being bromide in each case.

TABLE 8 Survival ratio (GB) Formula No. Reactivation rate 69 4/ Negligible 4/4 67 4/4 Preparation of Compounds 4-pyridinecarboxaldehyde oxime was prepared by war-ming on a steam bath a neutralized aqueous solution of 4-pyridinecarboxaldehyde and hydroxylamine hydrochloride. The oxime had a melting point of 130-1305 C. The 2- and 3-oximes were produced by similar methods.

The quaternization to produce dioximes was carried out by reacting the proper oxime with a 1, n dihaloalkane, (CH X employing a 3 :1 molar ratio of oxime to halide. The unsymmetrical quaternary monoximes were obtained by reacting the pyridine oxime with the appropriate omega-halopropyl quaternary salt in a 1.5:1 molar ratio. Two procedures were utilized.

Procedure A: A mixture of the pyridine oxime and halide was dissolved in sufficient ethanol and refluxed for the period of time specified in Table 9.

Procedure B: A mixture of the oxime and halide was dissolved in about 100 ml. of ethanol and heated in a 200 ml. capped pressure bottle (carbonated beverage type) for the length of time specified. The reaction mixtures were cooled to room temperature and the product removed by filtration. In several instances it was necessary to add absolute ether to eifect complete precipitation. The products were recrystallized from ether. This procedure was usually employed because of its simplicity.

Table 9 gives the procedure, yields and melting points for representative compounds.

TABLE 9 For- Substituents Melting (n1) mula Gondi- Yield or decom- No. tions percent position (d) Halide R R point, C.

I Br 35. 0 300 m. I Br 88. 2 238-241 (I. I Br 81.0 239-241 (I. I Br 95. 0 208-210 (1. I Br 85. 0 219-223 6.

II... 01 B, as hr 70 300 m. IVa Br (011m B, 60 r 68 208-211 m. IVai. Br (Slim B, 60 hr 226-231 m. 1%... Br B, 20 111:. 83.5 248-251 in. V Br (021393 B, 69 11L- 43 230-231 (1. V Br pyridine B, 64 11L- 10 223-226 (1.

mg. VIII." Br B, hr 16 201-203 (1.

Further details regarding the preparation and properties of certain of our compounds are given in the following publications by us and our associates:

Pyridine Alcloximes, by Edward J. Poziomek, Bernnie E. Hackley, Jr., and George M. Steinberg, Journal of Organic Chemistry, vol. 23, pp. 714-717 (May 1958); and Chemotherapeutic Effectiveness of T rimethylene Bis (4-Formy1 Pyridinium Bromide) Dioxime in Anticholinesterase Poisoning, by Edmund Bay, S. Kropp and L. F. Yates, Proceedings of the Society for Experimental Biology and Medicine, vol. 98, pages 107-109 (May 1958). These articles are to be considered incorporated by reference in this specification.

While we have shown a number of specific examples of compounds and their use, it will be obvious that various changes can be made without departing from our invention, which is defined by the following claim.

We claim:

A method of therapeutically treating a mammal which has been poisoned by a compound having high anticholinesterase activity which comprises injecting a composition comprising atropine and 1,1'-(2-butenylene) bis(4- formylpyridinium) halide dioxime.

' References Cited in the file of this patent Poziomek: Am. Chem. Soc. Abst. of Papers, 132nd Meeting, 1957, pages 16-0.