Showing papers on "Indole alkaloid published in 1982"

Detection of Pericine, a New CNS-active Indole Alkaloid from Picralima nitida Cell Suspension Culture by Opiate Receptor Binding Studies

Abstract: Successive fractionation of a crude methanolic extract of cultured PICRALIMA NITIDA cells accompanied by opiate receptor binding studies led to the detection and isolation of two compounds with opioid activity. The substances were identified as the indole alkaloids pericalline and pericine, the latter, as yet, not described. Half-maximal inhibition (IC 50 ) by the alkaloids was 2.3 μMol/l for pericalline and 0.6 μMol/l for pericine, values which lie within the micromolar range of the weak analgetic codeine (IC 50 : 3.6 μMol/l).

Studies on Plants containing Indole Alkaloids. VIII Indole Alkaloid Glycosides and Other Constituents of the Leaves of Uncaria rhynchophylla MIQ.

Abstract: A new glycoindole alkaloid, rhynchophine, was isolated from the leaves of Uncaria rhynchophylla MIQ. and its structure was elucidated as 6'-feruloyl vincoside lactam (IV). A partial synthesis was achieved by the use of vincoside lactam as the starting material. Five known compounds were also newly isolated from the same plant, namely, vallesiachotamine, vincoside lactam, strictosamide, hyperin and trifolin.

Structure of ngouniensine: an indole alkaloid of a new type from Strychnos ngouniensis

Abstract: The isolation and structure of ngouniensine (1), an indole alkaloid of a new type, are described.

The configuration of (+)-evodiamine: a long-standing problem in the chemistry of indole alkaloids

Abstract: The absolute configuration (S) of the long-known indole alkaloid (+)-evodiamine (1) has been established by correlation with (S)-tryptohpan via(7S,13bS)- carboxyevodiamine (2).

Evolution of Indole Alkaloids in Apocynaceae

Abstract: The indole alkaloids are outstanding among secondary plant metabolites in their structural intricacy and diversity. Tryptophan and secologanin, through their condensation product vincoside (code I, Table 9.1) as intermediate, are responsible for the biosynthesis of three indole alkaloid groups, characterized by different basic carbon skeletons, the corynanthe (codes prefixed I → V), aspidosperma (codes prefixed VI →, except for VI.3 →), and iboga (codes VI.3 types. The code of each skeleton of the indole alkaloids (Table 9.1) indicates its position on a biogenetic map. Comments on the construction of such maps, as well as their use in the determination of specialization values (S) for skeleta, together with rules for the determination of oxidation values (O) of compounds, are presented in Chapter 6. With reference to the latter topic, the point value for a carboxyl, which is of course (oxy- + oxo-functions) 3, is included even for skeletons which have lost this group during their biosynthesis, since such loss does not imply diminution of oxidation level (cf. Chap. 5).