Alkaloids, continued tropane

This group of alkaloids continues to attract some attention, and the contributions published during the period under review range in emphasis from the purely pharmacological to the purely mechanistic aspects of organic chemistry. As well as reports on the isolation of new alkaloids, attempts to find new pharmaceuticals, and improved methods of assay, the recent publications include studies in which tropane derivatives have been used as a convenient vehicle for conformational and mechanistic studies. 

Altogether 139 tropane alkaloids sensu stricto) have been isolated from different plant sources. The intensity of the search for new tropane alkaloids can be expected to continue. Although chemical syntheses have been developed for the basic tropane alkaloids, most of the pharmaceutically important alkaloids are more economically obtained in an industrial scale by extraction from plant material. This will probably be true in the immediate future as well. 

According to the well estabhshed use of these compounds in medicine, the demand for them is continuous [11-13, 36]. For this reason, much effort has been invested in the development of cost -effective strategies for tropane alkaloids production. 

The tropane alkaloids are a large important class of natural products which have variety of chemical structures and interesting pharmacological activities. These alkaloids are characteristic secondary metabolites for the families Solanaceae, Convolvulaceae, Erythroxylaceae, Proteaceae, and Rhizophoraceae, and they have been used as chemotaxonomical markers. The intensive investigations in the branch of tropane alkaloid chemistry continue and by the use of modem physical detection techniques, the number of new compounds steadily increases. 

Table 3.1 Occurrence of the most frequent types of pyrrolidine, tobacco, and tropane alkaloids in the Solanaceae proved by isolation or chromatographic methods (PC, TLC, GC/MS) tropanes mainly based on data of Lounasmaa and Tamminen (1993 and references therein). Classification according to Fig. 2.2 (continued)... 

Table 3.7 Occurrence of pyrrolidine, tobacco, and tropane alkaloids in both large Solanales families compared with the occurrence out of the Solanales. Data on tropanes based on Lounasmaa and Tamminen (1993), Griffin and Lin (2000) and references therein data concerning the Convolvulaceae based on the literature given in Table 3.2 (continued)... 

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