Application of azolylmethyloxiranes for the treatment of viral diseases
It is known that azole derivatives, eg. 2-α-hydroxybenzyl)-benzimidazole (cf. Burger&#39;s Medicinal Chemistry, IV. edition, 1979, part 2, page 554 et seq.) and hydroxyethylazoles, eg. 2-(4-chlorophenoxymethyl)-3,3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanol (=vibunazole, German Laid-Open Application DOS No. 3,238,903), as well as other members of this class of substances (German Laid-Open Application DOS No. 3,315,808), display antiviral activity. Azolylmethyloxiranes of the formula I ##STR2## where A and B are identical or different and are each alkyl of 1 to 4 carbon atoms, naphthyl, biphenyl or phenyl, and phenyl may be substituted by halogen, nitro, alkyl, alkoxy or haloalkyl, each of 1 to 4 carbon atoms, phenoxy or phenylsulfonyl, and Z is a CH group of a nitrogen atom, and their physiologically tolerated addition salts with acids are known to be highly effective local and systemic antimycotics (German Laid-Open Application DOS No. 3,218,129). 
     Surprisingly, we have found that the above azolylmethyloxiranes of the formula I also possess a very good antiviral action. 
     The compounds of the formula I contain chiral centers and are obtained in general in the form of racemates or diastereomer mixtures of erythro and threo forms. The erythro and threodiastereomers of the novel compounds can be separated, for example, on the basis of their different solubilities or by column chromatography, and can be isolated in pure form. Pure enantiomers can be obtained from such pure diasteromer pairs by conventional methods. Both the pure diastereomers or enantiomers and the mixtures of these obtained in the synthesis can be used as antiviral active compounds. 
     Specific examples of compounds of the formula I are the following: 
     
         __________________________________________________________________________
                                  Mp.                                     
No.                                                                       
   A          B         Z  Diastereomer                                   
                                  [°C.]                            
__________________________________________________________________________
 1 4-Cl--C.sub.6 H.sub.4                                                  
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        CH A      102-103                                 
 2 4-Cl--C.sub.6 H.sub.4                                                  
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        CH B      109                                     
 3 4-Cl--C.sub.6 H.sub.4                                                  
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        N  A      119                                     
 4 4-Br--C.sub.6 H.sub.4                                                  
              C.sub.6 H.sub.5                                             
                        CH A      152-153                                 
 5 4-Br--C.sub.6 H.sub.4                                                  
              4-Cl--C.sub.6 H.sub.4                                       
                        CH A      143-144                                 
 6 C.sub.6 H.sub.5                                                        
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        CH A      103                                     
 7 4-Br--C.sub.6 H.sub.4                                                  
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        CH A      107-100                                 
 8 4-4-Cl.sub.2 --C.sub.6 H.sub.3                                         
              4-Cl--C.sub.6 H.sub.4                                       
                        CH A      135                                     
 9 4-Cl--C.sub.6 H.sub.4                                                  
              C.sub.6 H.sub.5                                             
                        CH A      138                                     
10 4-Br--C.sub.6 H.sub.4                                                  
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        N  A      133-134                                 
11 CH.sub.3   2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        CH B        113-117.5                             
12 CH.sub.3   2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        CH A       98-104                                 
13 C(CH.sub.3).sub.3                                                      
              4-Cl--C.sub.6 H.sub.4                                       
                        N  A      79-80                                   
14 C(CH.sub.3).sub.3                                                      
              4-Cl--C.sub.6 H.sub.4                                       
                        CH A ×HCl                                   
                                  214-216                                 
15 C(CH.sub.3).sub.3                                                      
              C.sub.6 H.sub.5                                             
                        N  A ×HCl                                   
                                  148                                     
16 C(CH.sub.3).sub.3                                                      
              C.sub.6 H.sub.5                                             
                        CH A       75                                     
17 C(CH.sub.3).sub.3                                                      
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        N  A      124                                     
18 C(CH.sub.3).sub.3                                                      
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        CH A       95                                     
19 4-Cl--C.sub.6 H.sub.4                                                  
              4-C(CH.sub.3).sub.3 --C.sub.6 H.sub.4                       
                        CH B      160-162                                 
20 4-Cl--C.sub.6 H.sub.4                                                  
              4-C(CH.sub.3).sub.3 --C.sub.6 H.sub.4                       
                        N  A      176-177                                 
21 2,4-Cl.sub.2 --C.sub.6 H.sub.3                                         
              4-C(CH.sub.3).sub.3 --C.sub.6 H.sub.4                       
                        CH A      132-134                                 
22 CH.sub.3   2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        N  A      105-108                                 
23 CH.sub.3   2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        N  B      80- 85                                  
24 CH.sub.3   2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        N  A:B = 1:1                                      
                                  70-81                                   
25 4-C(CH.sub.3).sub.3 --C.sub.6 H.sub.4                                  
              4-Cl--C.sub.6 H.sub.4                                       
                        CH A      100-152                                 
26 4-C(CH.sub.3).sub.3 --C.sub.6 H.sub.4                                  
              4-Cl--C.sub.6 H.sub.4                                       
                        N  A      105-107                                 
27 4-C(CH.sub.3).sub.3 --C.sub.6 H.sub.4                                  
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        CH A      101-113                                 
28 4-C(CH.sub.3).sub.3 --C.sub.6 H.sub.4                                  
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        N  A      100-111                                 
29 4-Cl--C.sub.6 H.sub.4                                                  
              3-OCH.sub.3 --C.sub.6 H.sub.4                               
                        CH A ×H Cl                                  
                                  173                                     
30 4-Cl--C.sub.6 H.sub.4                                                  
              3-OCH.sub.3 --C.sub.6 H.sub.4                               
                        N  A       77                                     
31 C.sub.6 H.sub.5                                                        
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        N  A      159-161                                 
32 4-Cl--C.sub.6 H.sub.4                                                  
              3-Cf.sub.3 --C.sub.6 H.sub.4                                
                        CH A      101-104                                 
33 4-Cl--C.sub.6 H.sub.4                                                  
              3-CF.sub.3 --C.sub.6 H.sub.4                                
                        N  A      107-109                                 
34 C.sub.6 H.sub.5                                                        
              3-CF.sub.3 --C.sub.6 H.sub.4                                
                        CH A        77-78.5                               
35 C.sub.6 H.sub.5                                                        
              3-CF.sub.3 --C.sub.6 H.sub.4                                
                        N  A ×H Cl                                  
                                  131-133                                 
36 C.sub.6 H.sub.5                                                        
              C.sub.6 H.sub.5                                             
                        CH A      108-110                                 
37 4-Cl--C.sub.6 H.sub.4                                                  
              4-F--C.sub.6 H.sub.4                                        
                        CH A      130-132                                 
38 C.sub.6 H.sub.5                                                        
              4-Cl--C.sub.6 H.sub.4                                       
                        CH A      105-106                                 
39 C.sub.6 H.sub.5                                                        
              C.sub.6 H.sub.5                                             
                        N  A      116-118                                 
40 C.sub.6 H.sub.5                                                        
              4-Cl--C.sub.6 H.sub.4                                       
                        N  A      114-115                                 
41 4-Cl--C.sub.6 H.sub.4                                                  
              C.sub.6 H.sub.5                                             
                        N  A      106-110                                 
42 4-C.sub.6 H.sub.5 --C.sub.6 H.sub.4                                    
              4-Cl--C.sub.6 H.sub.4                                       
                        N  A      163-165                                 
43 4-Br--C.sub.6 H.sub.4                                                  
              C.sub.6 H.sub.5                                             
                        N  A      115-120                                 
44 4-Br--C.sub.6 H.sub.4                                                  
              4-Cl--C.sub.6 H.sub.4                                       
                        N  A      115-120                                 
45 4-Cl--C.sub.6 H.sub.4                                                  
              4-L--C.sub.6 H.sub.4                                        
                        N  A      112-117                                 
46 4-Cl--C.sub.6 H.sub.4                                                  
              4-Br--C.sub.6 H.sub.4                                       
                        N  A      115-119                                 
47 4-Cl--C.sub.6 H.sub.4                                                  
              4-Br--C.sub.6 H.sub. 4                                      
                        CH A      114-116                                 
48 4-Cl--C.sub.6 H.sub.4                                                  
              4-Br--C.sub.6 H.sub.4                                       
                        CH B      179-181                                 
49 2,4-Cl.sub.2 --C.sub.6 H.sub.3                                         
              4-Br--C.sub.6 H.sub.4                                       
                        CH A      135-139                                 
50 4-Cl--C.sub.6 H.sub.4                                                  
              4-F--C.sub.6 H.sub.4                                        
                        N  B      219-223                                 
51 4-Cl--C.sub.6 H.sub.4                                                  
              4-Br--C.sub.6 H.sub.4                                       
                        N  B      210-211                                 
52 2,4-Cl.sub.2 --C.sub.6 H.sub.3                                         
              4-Br--C.sub.6 H.sub.4                                       
                        N  A      108-110                                 
53 2,4-Cl.sub.2 --C.sub.6 H.sub.3                                         
              C.sub.6 H.sub.5                                             
                        CH A      Resin                                   
54 2,4-Cl.sub.2 --C.sub.6 H.sub.3                                         
              C.sub.6 H.sub.5                                             
                        CH B      118-121                                 
55 2,4-Cl.sub.2 --C.sub.6 H.sub.3                                         
              C.sub.6 H.sub.5                                             
                        N  A      Resin                                   
56 2,4-Cl.sub.2 --C.sub.6 H.sub.3                                         
              C.sub.6 H.sub.5                                             
                        N  B      Resin                                   
57 4-(SO.sub.2 --C.sub.6 H.sub.5)--C.sub.6 H.sub.4                        
              4-Cl--C.sub.6 H.sub.4                                       
                        CH A      193-195                                 
58 4-(SO.sub.2 --C.sub.6 H.sub.5)--C.sub.6 H.sub.4                        
              4-Cl--C.sub.6 H.sub.4                                       
                        CH B      204-205                                 
59 4-(SO.sub.2 --C.sub.6 H.sub.5)--C.sub.6 H.sub.4                        
              4-Cl--C.sub.6 H.sub.4                                       
                        N  A      132-135                                 
60 4-(SO.sub.2 --C.sub.6 H.sub.5)--C.sub.6 H.sub.4                        
              4-Cl--C.sub.6 H.sub.4                                       
                        N  B      175-177                                 
61 2,4-Cl.sub.2 --C.sub.6 H.sub.3                                         
              4-Cl--C.sub.6 H.sub.4                                       
                        N  A                                              
62 4-C.sub.6 H.sub.5 --C.sub.6 H.sub.4                                    
              4-Cl--C.sub.6 H.sub.4                                       
                        CH                                                
63 2-Cl--C.sub.6 H.sub.4                                                  
              4-Cl--C.sub.6 H.sub.4                                       
                        CH                                                
64 2-Cl--C.sub.6 H.sub.4                                                  
              4-Cl--C.sub.6 H.sub.4                                       
                        N                                                 
65 4-Cl--C.sub.6 H.sub.4                                                  
              3-Cl--C.sub.6 H.sub.4                                       
                        CH                                                
66 4-Cl--C.sub.6 H.sub.4                                                  
              3-Cl--C.sub.6 H.sub.4                                       
                        N                                                 
67 C.sub.6 H.sub.5                                                        
              3,4-Cl--C.sub.6 H.sub.3                                     
                        CH B      103-105                                 
68 C.sub.6 H.sub.5                                                        
              3,4-Cl--C.sub.6 H.sub.3                                     
                        N  A      Resin                                   
69 3,5-Cl.sub.2 --C.sub.6 H.sub.3                                         
              4-Cl--C.sub.6 H.sub.4                                       
                        CH                                                
70 3,5-Cl.sub.2 --C.sub.6 H.sub.3                                         
              4-Cl--C.sub.6 H.sub.4                                       
                        N                                                 
71 2-OCH.sub.3 --C.sub.6 H.sub.4                                          
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        CH                                                
72 2-OCH.sub.3 --C.sub.6 H.sub.4                                          
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        N                                                 
73 4-O--C(CH.sub.3).sub.3 --C.sub.6 H.sub.4                               
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        CH                                                
74 4-O--C(CH.sub.3).sub.3 --C.sub.6 H.sub.4                               
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        N                                                 
75 4-CH.sub.3 --C.sub.6 H.sub.4                                           
              C.sub.6 H.sub.5                                             
                        CH                                                
76 4-CH.sub.3 --C.sub.6 H.sub.4                                           
              C.sub.6 H.sub.5                                             
                        N                                                 
77 4-(O--C.sub.6 H.sub.5)--C.sub.6 H.sub.4                                
              4-Br--C.sub.6 H.sub.4                                       
                        CH                                                
78 4-(O--C.sub.6 H.sub.5)--C.sub.6 H.sub.4                                
              4-Br--C.sub.6 H.sub.4                                       
79 C.sub.6 H.sub.5                                                        
              4-NO.sub.2 --C.sub.6 H.sub.4                                
                        CH                                                
80 C.sub.6 H.sub.5                                                        
              4-NO.sub.2 --C.sub.6 H.sub.4                                
                        N                                                 
81 2-C.sub.10 H.sub.7                                                     
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        CH A      135                                     
82 2-C.sub.10 H.sub.7                                                     
              2,4-Cl.sub.2 --C.sub.6 H.sub.3                              
                        N  A      151                                     
83 4-Cl--C.sub.6 H.sub.4                                                  
              1-C.sub.10 H.sub.7                                          
                        CH                                                
84 4-Cl--C.sub.6 H.sub.4                                                  
              1-C.sub.10 H.sub.7                                          
                        N                                                 
85 4-Cl--C.sub.6 H.sub.4                                                  
              4-Cl--C.sub.6 H.sub.4                                       
                        CH A      115-120                                 
86 4-Cl--C.sub.6 H.sub.4                                                  
              4-Cl--C.sub.6 H.sub.4                                       
                        N  A      105-108                                 
87 2-C.sub.10 H.sub.7                                                     
              4-Cl--C.sub.6 H.sub.4                                       
                        CH A      140                                     
88 2-C.sub.10 H.sub.7                                                     
              4-Cl--C.sub.6 H.sub.4                                       
                        N  A      107                                     
89 2,4-Cl.sub.2 --C.sub.6 H.sub.3                                         
              4-C(CH.sub.3).sub.3 --C.sub.6 H.sub.4                       
                        CH B      142-143                                 
90 3,4-Cl.sub.2 --C.sub.6 H.sub.3                                         
              4-Br--C.sub.6 H.sub.4                                       
                        N  A      130-134                                 
91 4-Br--C.sub.6 H.sub.4                                                  
              4-F--C.sub.6 H.sub.4                                        
                        N  A      137                                     
92 4-Br--C.sub.6 H.sub.4                                                  
              4-F--C.sub.6 H.sub.4                                        
                        N  B      Oil                                     
93 4-Br--C.sub.6 H.sub.4                                                  
              4-F--C.sub.6 H.sub.4                                        
                        CH A      152                                     
94 C.sub.6 H.sub.5                                                        
              2-Cl--C.sub.6 H.sub.4                                       
                        N  A      158-159                                 
95 4-Cl--C.sub.6 H.sub.4                                                  
              2-Cl--C.sub.6 H.sub.4                                       
                        N  A      166                                     
96 C.sub.6 H.sub.5                                                        
              2-Cl--C.sub.6 H.sub.4                                       
                        CH A/B = 65:35                                    
                                  85-87                                   
97 4-Cl--C.sub.6 H.sub.4                                                  
              2-Cl--C.sub.6 H.sub.4                                       
                        CH A/B = 70:30                                    
                                  90-92                                   
__________________________________________________________________________
 
    
     Preferred compounds of the formula I are those in which A and B are each 3-chlorophenyl, 4-bromophenyl, 3-trifluoromethylphenyl, 2,6-dichlorophenyl, 4-tert-butylphenyl or in particular phenyl, 2-chlorophenyl, 4-chlorophenyl or 2,4-dichlorophenyl. 
     Antiviral agents can be prepared using either the pure diastereomers of enantiomers or their mixtures. 
     Conventional acids preferably used for the formation of physiologically tolerated salts are hydrohalic acids, eg. hydrochloric acid and hydrobromic acid, in particular hydrochloric acid, with which the novel compounds form particularly readily crystallizing salts, as well as phosphoric acid, nitric acid, sulfuric acid, monofunctional and bifunctional carboxylic acids and hydroxycarboxylic acids, such as acetic acid, oxalic acid, maleic acid, succinic acid, fumaric acid, tartaric acid, citric acid, salicylic acid, sorbic acid or lactic acid, and sulfonic acids, such as p-toluenesulfonic acid and naphthalene-1,5-disulfonic acid. 
     The compounds can be prepared by methods similar to those described in German Laid-Open Applications DOS Nos. 3,218,129 and 3,218,130. 
     For example, a compound of the formula II ##STR3## where A and B have the stated meanings and L is a leaving group which can be displaced by nucleophilic substitution, can be reacted with a compound of the formula III ##STR4## where Me is hydrogen or a metal atom and Z is a CH group or nitrogen. 
     Where Me is hydrogen, the reaction is carried out in the presence or absence of a solvent or diluent, with or without the addition of an inorganic base and with or without the addition of a reaction accelerator, at from 10° to 120° C. The preferred solvents or diluents include ketones, such as acetone, methyl ethyl ketone or cyclohexanone, nitriles, such as acetonitrile, esters, such as ethyl acetate, ethers, such as diethyl ether, tetrahydrofuran or dioxane, sulfoxides, such as dimethylsulfoxide, amides such as dimethylformamide, dimethylacetamide or N-methylpyrrolidone, and sulfolane, as well as mixtures of these. 
     Examples of suitable bases, which may also be used as acid acceptors in the reaction, are alkali metal hydroxides, such as lithium hydroxide, sodium hydroxide or potassium hydroxide, alkali metal carbonates, such as sodium carbonate, potassium carbonate, sodium bicarbonate or potassium bicarbonate, an excess of 1,2,4-triazole, pyridine or 4-dimethylaminopyridine. Other conventional bases may also be used. 
     Preferred reaction accelerators are metal halides, such as sodium iodide, potassium iodide, quaternary ammonium salts, such as tetrabutylammonium chloride, bromide or iodide or benzyltriethylammonium chloride or bromide, and crown ethers, such as 12-crown-4, 15-crown-5, 18-crown-6, dibenzo-18-crown-6 or dicyclohexano-18-crown-6. 
     The reaction is carried out in general at from 20° to 150° C. under atmospheric or superatmospheric pressure, continuously or batchwise. 
     Where Me is a metal atom, the reaction is carried out in the presence or absence of a solvent or diluent and with or without the addition of a strong inorganic or organic base, at from -10° to 120° C. The preferred solvents or diluents include amides, such as dimethylformamide, diethylformamide, dimethylacetamide, diethylacetamide, N-methylpyrrolidone, hexamethylphosphorotriamide, sulfoxides, such as dimethyl sulfoxide and finally sulfolane. 
     Examples of suitable bases, which may also be used as acid acceptors in the reaction, are alkali metal hydrides, such as lithium hydride, sodium hydride or potassium hydride, alkali metal amides, such as sodium amide or potassium amide, and sodium tert-butoxide, potassium tert-butoxide, triphenylmethyl-lithium, -sodium and -potassium and naphthalene-lithium, -sodium and -potassium. 
     The resulting compounds of the formula I are isolated by a conventional method, if necessary purified and, if desired, converted to their salts with physiologically tolerated acids. 
    
    
     The compounds of the formula I possess powerful antiviral activity, especially against herpes viruses, as shown in the Examples below (vibunazole is used as a comparative compound). 
     EXAMPLE A 
     Cell culture experiments 
     Herpes Simplex Virus (HSV) and human cytomegalovirus multiply readily in cultures of monkey kidney cells. The infections are distinguished by characteristic cytopathic effects (CPE) which occur about 8-12 hours after infection and can easily be observed and assessed. Antiviral properties of test substances which are non-toxic for the host cells or display their action against the infecting viruses in a concentration which is non-toxic for the cells can be readily characterized by the reduction of the cytopathic effect in this system. 
     The cells used were monkey kidney cells of the strain RC-37 Rita (Italodiagnostics, Rome), which were cultured in basal Eagle&#39;s medium (BME; Eagle, H., J. Exp. Med. 102, (1955), 595-601) until infection with the HSV-1 strains ANG (Schroder et al., Intervirology 6, (1976), 270-284) and WAL (Kirchner et al., J. Immunol. 117, (1978), 1753). On infection with the virus, the BME medium was replaced with medium 199 (Morgan et al., Proc. Soc. Exp. Biol., Med. 73 (1950), 1-8). The cells were infected after the formation of an almost confluent lawn with a multiplicity of two infectious virus particles [=2 PFU (plaque forming units)] per cell. The suspensions of the virus strains had titers of from 2×10 7  to 1×10 8  PFU/ml. The test substances were introduced in non-cytotoxic concentration into the medium of the infected cells at various times from 1 hour before to 2 hours after infection. The cytotoxicity limits were tested on the basis of growth curves and the colony-forming ability of isolated cells. The action of the substances was monitored in comparison with control cultures both by microscopic observation and by determining the progeny cell viruses. The virus titer was determined as described by Russell (Nature, London, 195 (1962), 1028-1029). 
     The compounds of the present invention exhibited substantially better inhibition of the CPE than vibunazole. The virus titer determined after application of the compounds I, in particular substance No. 3, was also substantially lower than in the case of the comparative compound. 
     EXAMPLE B 
     Testing the antiviral activity in the mouse model of the HSV infection 
     The experimental HSV infection of susceptible inbred strains of mice is today a well established, widely used experimental system for studying the pathogenicity of herpes viruses (Zisman et al., J. Immunol. 104 (1970), 1155-1159; Stevens and Cook, J. Epth. Med. 133 (1971), 19-38; Lopez, Nature London, 258 (1975), 152-153; Kirchner et al., Zeitsch. f. Immunitatsforsch. und exp. Therapie, 154 (1978), 147-154 and Kaerner et al., J. Virol., 46 (1983), 83-93). After peripheral (intraperitoneal) infection of mice with HSV-1, the infection initially spreads in the spleen; subsequently (from 3 to 4 days after infection), the virus attacks the central nervous system of the animals, passes into the brain and kills the mice about 8-10 days after infection by causing encephalitis. Compared with other peripheral methods of infection (eg. intravaginal, etc.), intraperitoneal infection has the advantage that metering can be carried out more exactly. 
     In the present tests, mice were infected intraperitoneally with with 10 6  PFU of HSV-1 WAL per animal. The substances to be tested were likewise administered intraperitoneally to the infected animals at various times after infection. The course of the disease was recorded. For all mice (both those which were killed and those which survived), the brains were examined for the presence of the infectious virus. 
     Administration of the compounds of the present invention, for example compound 3, resulted in a significant reduction in the mortality rate compared with the controls. The comparative compound had no effect in this respect. 
     EXAMPLE C 
     Testing the antiviral action in the guinea-pig (cutaneous infection model) 
     These tests were carried out essentially in accordance with the instructions given by Huber et al. (J. Invest. Dermatol. 62 (1974), 92-95). 
     Guinea-pigs weighing 400-500 g were epilated in the region of the rear flank, anesthetized with nembutal and infected intracutaneously with HSV-1 WAL (about 1×10 5  to 5×10 5  PFU/animal) using a Buntscheid multiple-needle gun. The substances to be tested were administered perorally by gavage at various times, (from 2 to 48 hours) after infection. The development and healing of virally caused lesions at the points of infection were monitored, and documented photographically. 
     While administration of the comparative compound had a statistically insignificant effect on the course of the infection compared with untreated controls, the compounds of the present invention, eg. compound 3, resulted in less pronounced development and more rapid healing of these virally caused lesions when used in the same dose. 
     The compounds of the formula I are therefore particularly useful for the enteral, parenteral and external treatment of DNA virus infections in humans and animals and thus constitutes a valuable enrichment of therapy. The following indications are specific examples of the application in humans: herpes labialis, herpes genitalis, herpes Zoster (shingles), varicella (chickenpox), keratoconjunctivitis herpetica, infectious mononucleosis and cytomegalovirus infections. Particular areas of use in veterinary medicine are pseudorabies virus infections in pigs and cattle, rhinotracheritis virus infections in cattle, rhinopneumonitis virus infections in horses and Marek&#39;s disease in hens. 
     The compounds can be used alone or together with other known active compounds, in particular antibiotics. 
     The chemotherapeutic agents or formulations are prepared in a conventional manner, in particular by mixing an appropriate dose with the conventional solid, semi-solid or liquid carriers or diluents and the conventional pharmaceutical auxiliaries, in accordance with the desired route of administration (cf. H. Sucker et al., Pharmazeutische Technologie, Thieme-Verlag, Stuttgart, 1978). 
     Examples of suitable forms for administration are tablets, coated tablets, capsules, pills, suppositories, aqueous solutions, suspensions and emulsions, and where appropriate sterile injectable solutions, non-aqueous emulsions, suspension and solutions, ointments, creams, pastes, lotions, etc. 
     The therapeutically active compound is preferably present in the pharmaceutical formulations in a concentration of from 0.5 to 90% by weight, based on the total mixture. 
     To achieve the desired results in the case of oral administration either in human or in veterinary medicine, the active compound or compounds can be administered in general in amounts of from about 0.1 to about 10.0, preferably from 0.2 to 6, mg/kg of body weight per day, preferably in the form of several single doses. However, is may be necessary to deviate from the stated doses, and to do this as a function of the nature and severity of the disorder, the type of formulation and the route of administration of the drug, as well as the period or interval between administrations. Thus, it may be sufficient in some cases to use less than the abovementioned amount of active compounds, while in other cases the above amount of active compound has to be exceeded. 
     Examples of pharmaceutical formulations: 
     EXAMPLE I 
     Tablets containing 250 mg of active compound Composition for 1000 tablets: 
     
         ______________________________________                                    
Active compound No. 3   250    g                                          
Potato starch           100    g                                          
Lactose                 50     g                                          
Gelatine solution (4% strength)                                           
                        45     g                                          
Talc                    10     g                                          
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     Preparation: 
     The finely powdered active compound, potato starch and lactose are mixed, the mixture is moistened thoroughly with the gelatine solution and then granulated to give fine particles, and the granules are dried. The dry granules are sieved and then mixed with talc, and the mixture is pressed in a rotary tableting machine to give tablets. The tablets are introduced into polypropylene containers which are closed tightly. 
     EXAMPLE II 
     Cream containing 1% of active compound 
     
         ______________________________________                                    
Active compound No. 3     1.0    g                                        
Glycerol monostearate     10.0   g                                        
Cetyl alcohol             4.0    g                                        
Polyethylene glycol-400 stearate                                          
                          10.0   g                                        
Polyethylene glycol sorbitan monostearate                                 
                          10.0   g                                        
Propylene glycol          6.0    g                                        
Methyl p-hydroxybenzoate  0.2    g                                        
Deionized water, to make up to                                            
                          100.0  g                                        
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     Preparation: 
     The very finely powdered active compound is suspended in propylene glycol, and the suspension is stirred into a melt, at 65° C., comprising glycerol monostearate, cetyl alcohol, polyethylene glycol-400 stearate and polyethylene glycol sorbitan monostearate. A solution, at 70° C., of methyl p-hydroxybenzoate in water is emulsified in this mixture, the emulsion is cooled, and the resulting cream is homogenized in a colloid mill and then introduced into tubes. 
     EXAMPLE III 
     Powder containing 1% of active compound 
     
         ______________________________________                                    
Active compound No. 3  1.0    g                                           
Zinc oxide             10.0   g                                           
Magnesium oxide        10.0   g                                           
Finely divided silica  2.5    g                                           
Magnesium stearate     1.0    g                                           
Talc                   75.5   g                                           
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     Preparation: 
     The active compound is micronized in a jet mill employing air, and is then mixed with the other components to give a homogeneous mixture. This is forced through a sieve of No. 7 mesh size and then introduced into polyethylene containers with a dusting attachment. 
     The Examples which follow illustrate the preparation of the compounds of the formula I. Preparation of the starting materials 
     Example a 
     63.6 g of potassium tert-butylate in 300 ml of dry methanol were introduced into a solution of 229 g of 2,4-dichlorobenzyltriphenylphosphonium chloride in 800 ml of dry methanol at 10° C., and 77.2 g of 4-chloroacetophenone were added after 0.5 hour. The reaction solution was refluxed for 3 hours, after which the precipitated salt was filtered off at room temperature and the filtrate was evaporated down under reduced pressure. By dispersing the residue with petroleum ether (50°-70° C.), triphenylphosphine oxide was separated off, and the solution was evaporated down under reduced pressure. The residue was taken up in 1 l of carbon tetrachloride, and the solution was refluxed with 81.7 g of N-bromosuccinimide and 4 g of 2,2&#39;-azobisisobutyronitrile. When the reaction was completed, the succinimide was filtered off, the filtrate was evaporated down under reduced pressure and the residue was recrystallized from methanol. 73.4 g (38.8%) of Z-1-(2,4-dichlorophenyl)-2-(4-chlorophenyl)-3-bromoprop-1-ene of melting point 128° C. were obtained. 
     Example b 
     58.9 g of Z-1-(2,4-dichlorophenyl)-2-(4-chlorophenyl)-3-bromo-prop-1-ene (cf. Example a) were refluxed with 52.3 g of 3-chloroperoxybenzoic acid in 590 ml of chloroform. When the reaction was complete, the chloroform phase was washed acid-free with aqueous sodium bicarbonate solution and water, dried with sodium sulfate and evaporated down under reduced pressure. When the residue was recrystallized from methanol, two crystalline fractions were obtained: 
     1. 41.3 g (70.2%) of 2-bromomethyl-2-(4-chlorophenyl)-3-(2,4-dichlorophenyl)-oxirane (isomer A) of melting point 98°-99° C. and 
     2. 12 g (20.4%) of 2-bromomethyl-2-(4-chlorophenyl)-3-(2,4-dichlorophenyl)-oxirane (isomer B) of melting point 93°-95° C. 
     Preparation of the end products 
     Example c 
     A solution of 10 g of 2-bromomethyl-2-(4-chlorophenyl)-3-(2,4-dichlorophenyl)-oxirane (isomer A; cf. Example b) in 50 ml of N,N-dimethylformamide was added dropwise, at 100° C., to a melt consisting of 15.6 g of imidazole and 1.37 g of sodium methylate, the methanol liberated having been distilled off from the melt beforehand. After 8 hours, the reaction solution was poured onto water and extracted with ethyl acetate, the organic phase was washed with water, dried over sodium sulfate and evaporated down under reduced pressure, and the residue was chromatographed over a silica gel column using a 100:2 methylene chloride/methanol mixture. The purified fractions were evaporated down, and the residue was crystallized from diisopropyl ether. 4.6 g (47.5%) of 2-(1H-imidazol-1-ylmethyl)-2-(4-chlorophenyl)-3-(2,4-dichlorophenyl)-oxirane (isomer A) of melting point 102°-103° C. were obtained. 
     The compounds listed on pages 3 to 6 can be prepared by methods similar to those described in Examples a to c.