Abstract
Cleavage reaction with metallic sodium or lithium in liquid ammonia was carried out on aporphine-type bases, (+)-O, O-dimethylcorytuberine (X) and (+)-glaucine (XIV), and the decomposition products were examined.
The starting compound, O, O-dimethylcorytuberine (X) was prepared by derivation of the quaternary base, magnoflorine iodide (IX) to its O, O-dimethyl compound and to the tertiary base (X) by the ethanolamine method. Glaucine (XIV) was also derived from the quaternary base, laurifoline iodide (XIII), by application of lithium aluminium hydride to its O, O-dimethyl compound.
Cleavage reaction of O, O-dimethylcorytuberine (X) in ether or tetrahydrofuran, using metallic alkali in liquid ammonia, gave two kinds of decomposition product. One of them was found to be the O-methyl compound of 2-methoxy-10-hydroxyaporphine (VI), obtained by the same cleavage reaction of O-methyldomesticine (V), i.e. 2, 10-dimethoxyaporphine (XI). The other was identified as 2-oxo-10-methoxy-1, 2, 3, 3a, 11b, 11c-hexahydroaporphine (XII).
The same reaction of (+)-glaucine (XIV) under the same conditions as above was found to form the entirely identical 2, 10-dimethoxyaporphine (XI) and the ketone compound (XII), as in the case of O, O-dimethylcorytuberine (X).
From the result of the foregoing experimental evidences, the absolute configuration of the steric structure of the starting bases used for this reaction, magnoflorine (IX), laurifoline (XIII), and O-methyldomesticine (V), can be related to (+)-glaucine (XIV) whose absolute configuration had already been clarified. These bases are now known to take the L-type configuration (S) as does (+)-glaucine.
