7-Oxo-dehydroabietamide (XI) derived from l-abietic acid (III) was converted to methoxycyano acid (XVI) via cyano lactone (XIII) and the intramolecular cyclization of XVI gave the expected 11-methoxy-7-oxo-dehydroabietonitrile (XVII). The cyclized compound (XVII) was converted to some 11-methoxy-dehydroabietic acid derivatives, which could be regarded as potential intermediates for synthesis of natural products having 11-hydroxyabietane skeleton.
