Alkaloids tryptophan

Analytical applications of pyrazolones have been reviewed by Busev et al. (65RCR237). Organic bases are easily characterized by formation of highly crystalline salts with picrolonic acid (l-(4-nitrophenyl-3-methyl-4-nitro-5-hydroxypyrazole). The last-named compound is used as a reagent for alkaloids, tryptophan, phenylalanine and for the detection and estimation of calcium (B-76MI40404). 

Indole alkaloids Tryptophane decarboxylase Catharanthus roseus Camptotheca acuminata... 

Use As reagent for alkaloids, tryptophan, phenylalanine, and for the detection and estimation of calcium. 

Biosynthesis In plants the quinoline system can be formed by several different biogenetic routes (biochemical convergence). In the Cinchona alkaloids tryptophan acts as the precursor while simple quinolines, furoquinolines, and acridines originate from an-thranilic acid. The second biosynthetic parmer is often a hemiterpene (for furoquinolines) or an iridoid monoterpene (secologanin, see secoiridoids) for Cinchona alkaloids. 

In these organisms, precursors of the ergot alkaloids tryptophan and mevalonic acid are the same as in Claviceps. Composition of the media and the cultivation conditions are rather specific for the production of the alkaloids by these strains. 

During the biosynthesis of ergoline alkaloids, tryptophan is decar-boxylated, isoprenylated at the 4 position, and methylated at the amino nitrogen. Neither tryptamine (Baxter et al., 1961 Floss and Groger, 1963) nor A"-methyltryptamine (Floss and Groger, 1963) was incorporated into the alkaloids. This ruled out decarboxylation as the first step. The tritium label from N -[side c/zam- C,m r/zj/- H]methyltryptophan was lost (Floss and Grdger, 1964). Only the tryptophan part was incorporated, the A-methyl... 

Bisindole Alkaloids from Tryptophan. There are two widely different types of alkaloids derived from two tryptophan (26) units. The first is a rather small group of compounds based simply on the dimers of tryptophan which includes compounds such as calycanthine (113) (Table 10),... 

Miscellaneous Alkaloids. Stukimic acid (57) is a precursor of anthranihc acid (28) and, in yeasts and Escherichia coli (a bacterium), anthranHic acid (o-aminobenzoic acid) is known to serve as a precursor of tryptophan (26). A similar but yet unknown path is presumed to operate in higher plants. Nonetheless, anthranHic acid itself is recognized as a precursor to a number of alkaloids. Thus damascenine [483-64-7] (134), C qH NO, from the seed coats of JSHgella damascena has been shown (95) to incorporate labeled anthranHic acid when unripe seeds of the plant are incubated with labeled precursor. 

The preferred formation of 261 over 260 is in accord with the well-known positional order 3 > 2 for reactivity of unsubstituted indole. Aiming at total synthesis of leptosin alkaloids, an application of this methodology to the 1-hydroxy-L-tryptophan derivatives seems to be promising. 

No 1 -hydroxytryptamine or -tryptophan alkaloid that lacks a stabilizing group on the indole nucleus has been reported yet. However, isolation of37,38a, 38b, HUN-7293 (293) (96MI69), and apicidin (301) (96TL8077) offers indirect evidence for the existence of 1-hydroxytryptamines and/or 1-hydroxytryptophans in living organisms. We believe their isolation will be reported in the near future. 

Wiesler U-M, Weil T, Mullen K (2001) Nanosized Polyphenylene Dendrimers. 212 1-40 Williams RM, Stocking EM, Sanz-Cervera JF (2000) Biosynthesis of Prenylated Alkaloids Derived from Tryptophan. 209 97-173 Wirth T (2000) Introduction and General Aspects. 208 1-5 Wirth T (2003) Introduction and General Aspects. 224 1-4... 

Williams RM, Stocking EM, Sanz-Cervera JF (2000) Biosynthesis of Prenylated Alkaloids Derived from Tryptophan. 209 97-173... 

Rebek, J., Jr., Tai, D.R, Shue, Y.K. (1984) Synthesis of Ergot Alkaloids from Tryptophan. Journal of the American Chemical Society, 106, 1813-1819. 

These epipolythiodiketopiperazine alkaloids, together with the calycanthaceous alkaloids (Fig. 9.1b), form a superfamily of natural products termed the dimeric hexahydropyrroloindole alkaloids [6-8]. The main dichotomy within this superfamily arises from the biogenetic elaboration of tryptamine versus tryptophan building blocks. The tryptamine-based calycanthaceous alkaloids, boasting members such as chimonanthine (7), calycanthine (9), and folicanthine (8), are largely plant derived and have a long and rich history in the context of natural product synthesis [7, 9]. 

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