| abstract |
Compounds of the formulan in which R and R, are the same or different and each can be hydrogen, alkyl of from 1 to 3 carbon atoms, cycloalkyl- C-C 3 -alkyl, wherein the cycloalkyl radical has 3 - carbon atoms, or aralkyl having up to 8 carbon atoms, X and Y are the same or different and each can be chlorine, bromine, fluorine, alkoxy or alkyl, each of from 1 to 3 carbon atoms, hydroxy, or trifluoromethyl, m is the integer 0,1 or 2, n is the integer 0,1,2 or 3, the optical antipodes thereof, physiologically acceptable salts thereof, and pharmaceutical compositions containing them. They are prepared by the cyclisation of compounds of the formulan with a compound of the formula |