alkaloid, curine. The latter was shown by Spath^^ to be identical with 

 bebeerine. Spathll later suggested the correct formula, for v/hich Kingl2 

 gave experimentiil evidence in 1939. This involved a two- stage Hofmann 

 degradation of dimethyl bebeerine to the methyl bebeerilene, subsequent 

 oxidation to the two acidic fractions shovm, and finally the synthesis 

 of both of these molecules for comparison. 



The most direct way of attacking our problem would be to purchase some 

 bebeerine and to test its activity against marine borers. Unfortunately, 

 the matter was not quite so simple, as there were no suppliers. 



The best source for bebeerine still appeared to be pareira brava. However, 

 the bebeerine content of this material varies from about 3o;> of the crude 

 alkaloids to little or no bebeerinelO, and the bebeerine obtained can be 

 the levorotatory, the dextrorotatory, or the racemic form. 13 



Some pareira brava was obtained and the alkaloids were extracted esentially 

 according to the procedure employed by Kingl'^, which is shovm in Figure 5. 



According to previous vrorkers, ^ -^^ ^ the ether-soluble alkaloids are 

 dissolved in methyl alcohol, and, on standing, crystals of bebeerine 

 separate. Hov^ever, the pareira brava which we extracted contained little 

 or no bebeerine, The crude alkaloids were separated into a large number 

 of fractions, none of which, according to their pi^operties, contained 

 bebeerine. 



Similar results were obtained v/ith a second shipment of pareira brava from 

 a different supplier, 



/Jfter much letter writing a firm in Scotland was located v/hich had available 

 a one pound quantity of commercial "Bebeerine Hydrochloride." From this 

 black material we obtained the free bases vfhich virere conspicuously similar 

 to those which we isolated from pareira brava. In fact, it tuxned out 

 that the "Bebeerine Hydrochloride" did consist of the hydrochlorides of 

 the total alkaloids from the root of pai'eira brava. 



The crude bases from the "Bebeerine Hydrochloride" were extracted successively 

 with benzene, methylene chloride, and methyl alcohol. The total solids from 

 the benzene extract were dissolved in methyl alcohol, j/hen the solution 

 was cooled, a v/hite precipitate (12?^ based on the crude alkaloids) melting 

 at 28^° was obtained. The material remaining in solution was separated by 

 the process of "fractional crystallization" into eight amorphous fractions, 

 which according to their properties consisted of four or more compounds. 

 The methyl alcohol extract was similarly separated into six fractions con- 

 sisting again of four or more compounds. 



The material melting at 285° v^as recrystallized from methyl alcohol and^ 

 chromatographed on alumina to give crystalline isochondrodendrine, melting 

 at 302°, The material had the exijected physical and chemical propertie| 

 and its identity was confirmed by the preparation of the dimethiodide«15 



N - U 



