Harmine, basicity

The numbering of the carboline system was later modified to that shown in 4, and the position of the basic nitrogen in the pyridine ring was designated by a Greek letter. Harmine thus became 8-methoxy-2-... 

The ionization constants of the first excited states of p-carboline and three of its derivatives - harmane. harmine, and 2-methylharmine - have been re-ported, and the fluorescence and phosphorescence spectra of harmine, harmaline, and 3-dehydroreserpines have been determined in neutral, acidic, and basic solution at 298 and 77 K. The photo-oxidation of 3-dehydroreserpines has also been examined in this work. The luminescence spectra of a series of indole alkaloids have also been reported by the same workers. The effect of pH on the absorption and fluorescence spectra of sanquinonine, a benzophenanthridine alkaloid, have been studied in detail. 

Harmaline, A substance forming yellowish prismatic crystals, obtained from the Peganum Harmala, a plant abounding in southern Russia. By oxidation it yields Harmine, a fine red dye-stuff, also possessing basic properties,... 

Ajmaline, berbamine, berberine, boldine, cinchonine, cinchonidine, ergometrine, harmalin, harmin, lobeline, norharman, papaverine, quinidine, quinine, sanguinarine, and solanine affect more than one of the basic... 

In the course of basic studies in the germination metabolites of Peganum harmala seeds, it was discovered that the alkaloidal constituents are located in the husk and the kernel yields 20% of oil comparable in its constants and constituents to those of cotton seed oil [9]. However, the economic viability of harmal seeds as a new source of edible oil would largely depend on the utilization of alkaloids from the husk which constitutes 50% of the whole seed and contain ca. 7% of the alkaloidal bases. In view of this fact, intensive studies have been undertaken on the chemistry of the two main alkaloids of harmala, namely harmine, harmidine, and their derivatives, and a whole series of new potentially pharmacophoric derivatives of these bases have been prepared [10]. 

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