Method of tranquilizing animals
United States Patent 1191 Wehrmeister 51 Apr. 22, 1975 METHOD OF TRANQUILIZING ANIMALS [75] Inventor: Herbert L. Wehrmeister, Terre Haute, Ind.  
 [73] Assignee: Commercial Solvents Corporation,  
 Terre Haute, Ind.  
 [22] Filed: Dec. 4, 1972 [21] Appl. No.: 312,078  
 OTHER PUBLICATIONS Chem. Abst. (1), 7l 81347J (1969). Chem. Abst. (2), 7l 38861K (1969). Handrick et al.. J. Med. Chem.. 8 762466, (1965).  
 Primary E.\&#39;umincr-Stanley J. Friedman Allurm&#39;y. Agent. or Firm-Robert H. Dewey; Howard E. Post [57] ABSTRACT A method of tranquilizing warm-blooded animals comprising administering thereto orally or intravenously a tranquilizing amount of a compound. or a phramaceutically acceptable salt thereof. corresponding to the formula where X is -O or -S, R and R are hydrogen, methyl or hydroxymethyl and are the same or differem. and Z is methyl, ethyl, methoxymethyl, pmethoxyphenyl; or 4.4-dimethyl-2oxazolylethyl; 4.4-dimethyl-2-oxazolylbutyl; or the group R2 CH3 where R&#39;-&#39; is hydrogen. chloroor dimethylamino-.  
 3 Claims, N0 Drawings METHOD OF TRANQUILIZING ANIMALS BACKGROUND OF THE INVENTION This invention relates to a method of tranquilizing warm-blooded animals. In a particular aspect. this invention relates to a method of tranquilizing animals by administering thereto an oxazoline or thiazoline.  
  Tranquilizing agents are very useful in calming animals. For example. in veterinary medicine and in zool ogy they are very helpful treating sick animals and in the capture and transportation of wild animals. Many tranquilizing agents are known. among which are oxazolines of the formula where R is halogenyl phenyl. o-hydroxyphenyl or mtrifluoro methyl. as disclosed by L. F. Wiggins et al. U.S. Pat. No. 3.235.557.  
 SUMMARY OF THE INVENTION are tranquilizing agents when administered to warmblooded animals. In the formula. X is 0 or S; R and R are hydrogen. methyl or hydroxymethyl and are the same or different; Z is methyl. ethyl. methoxymethyl or p-methoxyphcnyl; or Z is 4.4-dimethyl-2- oxazolylcthyl or 4.4-dimethyl-Z-oxazolylbutyl; or Z is the group where R is hydrogen. chloro-. or dimethylamino-.  
 DETAILED DISCUSSION The oxazolines of the present invention wherein Z is are known in the art. They can be readily prepared by the method of H. L. Wehrmeister. J. Org. Chem. 27. 4418 (1962) by condensing benzaldehyde or the appropriate substituted benzaldehyde with a 2-ethyl-2- oxazoline. When Z is 4.4-dimethyl-2-oxazolylethyl or oxazolylbutyl. the compounds can be prepared by condensing two moles of an appropriate alkanolamine with a dibasic acid. e.g. adipic or succinic acid. by known methods. e.g. the method of Purcell. cited hereinbclow. 4.4-Dimethyl-Z-ethyl-Z-thiazoline of Example 8 is a known compound. commercially available. or it can be prepared by the method of G. R. Handrick et al.. J. Med. Chem. 8. 762 1965).  
  The oxazolines wherein Z is p-methoxyphenyl or methoxymethyl can be readily prepared by known methods. eg the method of Purcell. U.S. Pat. No. 3.336.145. by condensing an alkanolamine corresponding to the formula R c ca oa l NH where R and R have the same meaning set forth before. with an appropriate acid. e.g. pmethoxybenzoic acid or methoxyacetic acid.  
  The compounds of the present invention have been found to exert a depressant action on the central nervous system when tested under standard and accepted pharmacological procedures. in aninmals. such as mice. They are. therefore. deemed to possess utility in experimental and comparative pharmacology and are of value to treat conditions in animals. such as valuable domestic animals. and in laboratory animals. such as mice. rats and the like. responsive to treatment with central nervous system depressant agents. Specifically. the compounds may be employed to induce a calming effect in animals.  
  In the pharmacological evaluation of the biological activity of the compounds of this invention. the in vivo effects were tested by two different tests. In one. the oral toxicity was determined by administration to a group of laboratory mice. A trained observer watched the mice closely for several hours and noted decreased motor activity. The second test was that described by Horn. Biometrics. l2z3ll (1956). In this test. laboratory mice received the test compound (two mice per dose level) at one-half log-dosage intervals by intravenous injection. The animals were observed by trained observers and pharmacological signs of tranquilization were noted. The median lethal dose (LDsa) and the median effective dose (MED-, for tranquilization were estimated. The safety factor was taken as the ratio of 5o/ 50- The compounds of this invention are active as central nervous depressants at an oral dose of generally in the range of about I to about 1.000 mg/kg. However most compounds will be effective within the range of 10-100 mg/kg. When administered intravenously. a dosage within the range of about 1.8 560.0 mg/kg is effective. but a dosage within the range of 3.2 180.0 mg/kg is generally sufficient. In many cases a dosage within the range of 5.6 100.0 mg/kg will be satisfactory.  
  These compounds are weakly alkaline and readily form salts with most acids. Many of these salts are water-soluble and advantageously can be used for administering these compounds. The invention therefore contemplates the administration of pharmaceutically acceptable salts of these oxazolines and thiazolines as well as the unneutralized compounds themselves.  
  This invention will be better understood by reference to the following examples. It is understood. however. that these examples are intended for illustration only. and it is not intended that the invention be limited thereby.  
 EXAMPLE 1 1.2-bisl 2-( 4.4-dimethyl-2-oxazolyl lethane (P- 191 l b.p. l24-l34 at 10 mm. was prepared by reacting succinic acid 1 mole) with 2-amino-2-methyl-lpropanol (2 moles) by methods known in the art.  
  The acute oral LD in mice was determined to be 2.000 t 167 mg/kg. The LD was 1.500 mg/kg and the LD was 3.000 mg/kg. Animals receiving the compound were tranquilized.  
  The product was additionally tested by the method of Horn described above. The LD by intravenous administration was greater than 320.0 mg/kg. The median effective dose for tranquilization was (10.0-100.0) and the safety factor was greater than 10.0.  
 EXAMPLE 2 The experiment of Example 1 was repeated in all essential details except that adipic acid was substituted for succinic acid on an equi-molar basis. The product. 1.4-bis-l 2-( 4.4-dimethyl-2-oxazolyl butane (P-l 920) was administered orally to white mice. The LD was 875 mg/kg. the LD.-,., 1.560 1 130 mg/kg. and the LD was 2.800 mg/kg. Animals receiving the compound were tranquilized.  
  The product was additionally tested by the method of Horn. The L1 by intravenous administration was 180.0 mg/kg (560-5600). The median effective dose for tranquilization was 56.0 mg/kg (18.0-180.0) and the safety factor was 3.2.  
 EXAMPLE 3 Benzaldehyde was reacted with 4.4-dimethyl-2-ethyl- 2-oxazoline to produce 4,4-dimethyl-2-(1-methyl-2- phenylethenyl)-2-oxazoline (P-l885), b.p. 109-1l0 at 0.1-0.3 mm and l37-l 38 at 4.0 mm. It was administered to mice to determine the oral toxicity. The LD was approximately 5.500 mg/kg. The LD was 1,500 mg/kg and the LD was approximately g/kg. It was a very active tranquilizer.  
  The compound was further tested by the method of Horn. The LD.-, by intravenous administration was 180 (56-560) mg/kg. and the median effective dose for tranquilization was 5.6 mg/kg (1.8-18.0). The safety ratio was 32.0.  
 EXAMPLE 4 4,4-Dimethyl2-p-methoxyphenyl-Z-oxazoline (P- 1873 b.p. l48l54&#39;at 1.0 mm, was prepared by condensing p-methoxybenzoic acid and 2-amino-2-methyl- 32.0 mg/kg l-propanol by the method of Purcell cited hereinbefore. The acute oral LD was determined to be 2.780 mg/kg. The LD was 1.500 mg/kg and the LD was 4.500 mg/kg. Animals receiving it were tranquilized.  
  The product was additionally tested by the method of Horn. The LD by 1 intravenous administration was 180.0 (56.0-560.0) mg/kg. The median effective dose was 32.0 mg/kg (10.0-100.0) and the safety factor was 5.6.  
 EXAMPLE 5 2.4.4Trimethyl-2-oxazoline (P-19l9). a known compound. was administered orally to laboratory white mice. Animals receiving it were observed to be tranquilized. The oral LD was 1.700 mg/kg. the LD was 2.800 mg/kg and the LD was greater than 5.000 mg/kg.  
  The compound was additionally tested by the method of Horn. The LD by intravenous administration was greater than 3200 mg/kg. The median effective dose for tranquilization was 10.0 mg/kg (3.232.0). The safety factor was greater than 32.0.  
 EXAMPLE 6 2-( 2-p-Chlorophenyll-methylethenyl )-4- hydroxymethyl-4-methyl-2-oxazoline (P-l580) was synthesized from 2-ethyl-4-hydroxymethyl-4-methyl-2- oxazoline and p-chlorobenzaldehyde.  
  The acute LD by oral administration to miceywas determined to be 2.750 1 355 mg/kg. The Lo w eepg proximately 1.500 mg/kg and the LD approximately 5.000 mg/kg. Animals receiving the compound were tranquilized.  
  The compound was additionally tested by the method of Horn. The LD by intravenous administration was mg/kg (56-560); the median effective dose for tranquilization was 18.0 mg/kg (5.6-56 the safety factor was 10.  
 EXAMPLE 7 4.4-Dimethyl-2-(p-dimethylaminophenyl)-lmethylethenyl-2-oxazo1ine (P-1889) was made by reacting p-dimethylaminobenzaldehyde with 4.4- dimethyl-2-ethyl-2-oxazoline.  
  The acute LD by oral administration to mice was 2.350 :t 260 mg/kg. The LD was 1.500 mg/kg and the LD was 3.000 mg/kg. Animals receiving the compound were moderately tranquilized.  
  The compound was additionally tested by the method of Horn. The LD by intravenous administration was 180 (56-560) mg/kg and the median effective dose for tranquilization was 10 (3.2-32.0) mg/kg. The safety factor was 18.0.  
 EXAMPLE 8 2-Ethyl-4,4-dimethyl-2-thiazoline (P-l92l) was administered orally to laboratory mice. Animals receiving it were tranquilized. The oral LD was 740 mg/kg. the LD was 930 mg/kg and the LD was 1.150 mg/kg. The compound is administered orally to animals in need of tranquilizing in a dosage of from about 18 to about 180 mg/kg.  
  The compound was additionally tested by the method of Horn. The LD by intravenous administration was 180.0 mg/kg (560-5600) and median effective dose for tranquilization was 5.6 mg/kg (l.8-18.0). The safety factor was 32.0.  
 EXAMPLE 9 I claim:  
  1. A method of tranquilizing a warm-blooded animal comprising administering to a warm-blooded animal in need of such treatment a tranquilizing amount of the compound Z-ethyl-4.4-dimethyl-2-thiazoline or a pharmaceutically acceptable salt thereof in an oral dosage of from about 1.8 to about 18 mg/kg or by administering a pharmaceutically acceptable salt thereof intravenously.  
  2. The method of claim 1 wherein said compound is administered intravenously in a dosage of about 1.8 to about 18.0 mg/kg.  
  3. The method of claim 1 wherein the said compound is administered in the form of a pharmaceutically acceptable salt.