METHOD OF PRODUCING 2,3-POLYMETHYLENE-4-OXO-4N-PYRIDO-/1,2-A/-PYRIMIDINES OR THEIR TERTIARY SALTS

Pharmaceutical intermediates, morphine potentiators and other compounds have the formula wherein R is hydrogen, halogen, C1-4 alkyl, hydroxy, nitro, amino, carboxy or a carboxylic acid derivate radical, R1 is hydrogen or a C1-4 alkyl, R2 is hydrogen or C1-4 alkyl, R3 is hydrogen, R4 is hydrogen or C1-4 alkyl, R5 is hydrogen R6 is hydrogen or R3 and R4 and/or R5 and R6 form a chemical bond, X is oxygen or imino, m is 1, 2, 3 or 4, n is 0, 1, 2 or 3, and if n is 1, then the dotted lines can stand for bonds, with the proviso that if m=1 and n=1 and if in the 2,3-, 6,7-, 8,9- and 1,10-positions double bonds are present, and R1 and R2 are hydrogen, then R is other than 9-hydroxy or 9-methyl; if m=2 and n=1 and R2 is hydrogen, then at least one of R and R1 is other than hydrogen; and if m=2 and n=2 and R2 is hydrogen and the molecule is a 2,3,4,6,7,8,9,10-octahydro derivative, then at least one of R and R1 is other than hydrogen or an acid-addition or quaternary salt thereof.