Lobinine group

LELOBINE AND LOBININE GROUPS. These include the minor alkaloids of lobelia isolated from factory residues accumulated during the manufacture of lobeline. Their isolation and separation involve complicated processes of fractionation for which the original paper should be consulted. Their inter-relationships (Table A, p. 23 and general formula, I, p. 24) are similar to those among members of the lobeline group, but the effect of the presence of three or more asymmetric carbon atoms is more evident, thus there are already known six forms of the basic dihydric alcohol, lelobaiiidine. 

Exhaustive Methylation. As in the lobeline group it is the diketo-bases, lelobanines (p. 30) in the lelobine series and lobinanines (p. 31) in the lobinine group, which give methiodides amenable to this mode of degradation. They are decomposed by alkali yielding an unsaturated neutral oil, which is hydrogenated and then, if necessary, oxidised to the saturated open chain diketone, e.g., see under lelobanine. 

The chief descriptive characters and reaction products of the lelobine series are recorded in Table B, and those of the lobinine group in Table C. The constitutional formulas assigned to the principal members of each group are shown on p. 32. 

Lobinanidines, CigH2702N (XXII). Four of these substances are known two, lobinanidine and uolobinanidine, occur naturally and, two, -lobinanidine and -isolobinanidine, are produced by the reduction of lobinine and isolobinine respectively witli sodium amalgam in acetic acid, the carbonyl group (as in XX) being reduced without saturation of the nuclear ethylenic linkage. For descriptive characters, see Table C. 

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