Cularine absolute configuration

The absolute configuration of cularine and its relatives has been determined by chemical correlation to L(S)-romneine (57) which had previously been related to L-(S)-laudanosine. The new configuration (58) is in contradiction to that previously assigned 75). 

The proaporphine, promorphinane, and cularine alkaloids can be reconverted into the benzyltetrahydroisoquinoline bases with sodium in liquid ammonia, a process which permits correlation of the absolute configurations of the benzyltetrahydroisoquinoline, proaporphine, aporphine, promorphinane, and cularine alkaloids (375). 

The absolute configuration of naturally occurring (+ )-cularine (55) has been firmly established by its chemical correlation with ( + )-romneine (56) of established absolute configuration. ... 

Originally the absolute configuration of (+)-cularine (11) was suggested to be R) by optical rotatory dispersion measurements of its sodium-liquid ammonia... 

The absolute configuration of cularine has been shown to be d = R from the optical rotatory dispersion of its hydrogenolysis product (V). The hydrochloride, methiodide, and 0-acetate of V showed complete reversal of the long w avelength Cotton effect and circular dichroism... 

Kametani T, Honda T, Shimanouchi H, Sasada Y (1972) Absolute configuration of the alkaloid cularine an X-ray structure determination. Chem Commun 1072-1073... 

Kunitomo J, Morimoto K, Yamamoto K, Yoshikawa Y, Azuma K, Fujitani K (1971). The absolute configuration of cularine A chemical correlation to L(S)4audanosine. Chem Pharm Bull (Japan) 19 2197-2199... 

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