Process for the preparation of therapeutically useful 6-ester derivatives of 4a, 5,9,10,11,12-hexahydro-11-methyl-6H-benzofuro 3a, 3,2-ef 2 benzazepine-3,6-diol

摘要

A compound of the formula (II) CHEM wherein R1 is hydrogen, (C1-C12)alkylcarbonyl, (C1-C12)alkoxycarbonyl, mono(C1-C12)alkylaminocarbonyl or di(C1-C8)alkylaminocarbonyl; R2 hydrogen, nitrogen containing heterocyclyloxy, or nitrogen containing heterocyclylcarbonyloxy; wherein the heterocyclyl groups are selected from 5 or 6 membered saturated or partially unsaturated rings, optionally fused to another saturated, unsaturated or aromatic ring; R3 is hydrogen, halo or (C1-C4)alkyl; R4 is hydrogen or (C1-C6)alkyl; with the proviso that R1 and R2 are not both hydrogen when R3 and R4 are hydrogen; all geometric, and optical and stereoisomers thereof, or a pharmaceutically acceptable addition salt thereof.