GB981046A — Hexahydro-4ah-8,9c-iminoethano phenanthro-[4,5-b,c,d]-furan derivatives

USPTO Abstract

The invention comprises compounds of general formula <FORM:0981046/C2/1> wherein R is hydrogen, alkyl, hydroxyalkyl or alkoxyalkyl, R1 is hydroxy, halogen or O.CO-alkyl, R11 is hydrogen, alkyl or C.OOH (alkyl groups contain from 1 to 6 carbon atoms), and X=X1 and is oxygen or sulphur or X is NH and X1 is S and n is 0 or 1, and the preparation thereof by reacting a compound of general formula <FORM:0981046/C2/2> wherein R and R1 have the above meanings with a compound of formula HX.CHR11.(CH2)n.CHR11.X1H, where X, X1, R11 and n have the above meanings, in the presence of an acid catalyst, for example, toluene-p-sulphonic acid, boron trifluoride etherate, or in the case of cysteine hydrochloride no additional acid catalyst is added. The compounds of general Formula I in which R1 is halogen may be formed from those in which R1 is hydroxy by treatment with the appropriate phosphoryl halide in 1,2-dichloroethane and dimethylformamide and heating at 65 DEG to 75 DEG C. for several hours. In addition, in an example a b -hydroxyethoxy group is formed at the 3-position by treating the corresponding 3-hydroxy compound of the first general formula above with ethylene carbonate. Pharmaceutical compositions having analgesic activity contain as the active ingredient the compounds of the first general formula above. The compositions may be in the form of tablets, lozenges, or injectable preparations. 5,6,7,7a,8,9 - Hexahydro - 7a - acetoxy (or propionoxy) - 3 - methoxy - 12 - methyl - 5 - oxo - 4aH-8, 9c - iminoethanophenanthro - [4,5-b, c, d] furan is prepared by treating the 7a-hydroxy compound with acetic or propionic anhydride at 100 DEG C. for 5 hours. 5,6,7,7a,8,9 - Hexahydro - 3 - ethoxy - 7a - hydroxy - 12 - methyl - 5 - oxo - 4aH - 8,9C - iminoethanophenanthro - [4,5-b, c, d] - furan is prepared by treating the corresponding 3-hydroxy compound with ethyl iodide and sodium hydroxide. The Provisional Specification also refers to compounds of the first general formula above wherein R11 represents COO-Alkyl.