Alkaloids monoterpene indole

Syntheses targeting an advanced core structure for the construction of closely related natural products are frequently reported. The discovery of common scaffolds, however, and its application in the synthesis of structurally diverse natural products in the so-called collective total synthesis is much less present in the literature. In the following section some of the most elegant collective syntheses of indole and bisindole natural products are presented. 

3 COLLECTIVE TOTAL SYNTHESIS OF TRYPTOPHAN-DERIVED ALKALOIDS 

SCHEME 14.2 MacMillan s synthesis of five members of natural indole alkaloids. 

Collective total synthesis has been gathering more and more attention recently. Prof Jieping Zhu s divergent synthesis toward five members of Aspidosperma alkaloids represent one of the most recent advancement (Fig. 14.14) [49]. The advantages in Prof Zhu s synthesis plan include (i) to construct the indole unit at a late stage of the synthesis instead 

FIGURE 14.14 Prof. Jieping Zhu s synthetic plan toward monoterpene indole alkaloids. 

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During the past two decades a great number of papers have been published on the isolation, structure elucidation, synthesis and transformation, biogenesis, chemotaxonomy, and pharmacology of indole alkaloids. In this chapter we summarize the new results that appeared from 1968 to mid 1984 for the cory-nantheine-yohimbine group of monoterpene indole alkaloids with greater emphasis on their chemistry, excluding the related oxindoles and heteroyohimbines. 

Geissoschizine (30) (7) is one of the most widely investigated monoterpene indole alkaloids. Since the first structure elucidation, carried out by Rapoport... 

This review of the biosynthesis of the bisindole alkaloids of C. roseus is organized along a developing biosynthetic pathway, as far as possible, and relies on the notion that the most sophisticated studies are those utilizing the purified enzyme systems. Biosynthetic studies on the other monoterpene indole alkaloids are not reviewed here. 

This is the latest volume in the series "The Alkaloids Chemistry and Biology and covers a group of alkaloids comprising the carbazole nucleus. Single-topic volumes in this series have been rare, and the last one discussed antitumor alkaloids and was published as Volume 25 in 1985. This is the first volume dedicated to a single alkaloid structure type since Volume 8, which dealt with the monoterpene indole alkaloids over 40 years ago. 

Keywords alkaloid biosynthesis alkaloid genes nicotine tropane alkaloids pyrrolizidine alkaloids benzylisoquinoline alkaloids monoterpene indole alkaloids ergot alkaloids acridone alkaloids purine alkaloids taxol betalains... 

Stereospecific condensation between tiyptamine and seco-loganin in a Mannich-like reaction is carried out by the enz)une (S)-strictosidine s)m-thase and results in the formation of the glucoalkaloid, (S)-strictosidine, from which most monoterpene indole alkaloids are derived (Figs. 2.1 and 2.9). 

Figure 2.13 Putative localization and intercellular trafficking of monoterpene indole alkaloids in Catharanthus roseus. (After Facchini and De Luca, 2008 Murata et a ., 2008.)...

Buriat, V., Oudin, A., Courtois, M., Rideau, M. and St. Pierre, B. (2004) Co-expression of three MEP pathway genes and geraniol-lO-hydroxylase in internal phloem parenchyma of Catharanthus roseus implicates multicellular location of intermediates during the biosynthesis of monoterpene indole alkaloids and isoprenoid-derived primary metabolites. Plant., 38,131 1. 

Schiel, O., Witte, L. and Berlin, J. (1987) Geraniol-lO-hydroxylase activity and its relation to monoterpene indole alkaloid accumulation in cell suspension cultures of Catharanthus roseus. Z. Naturforsch., 42c, 1075-81. 

Strictosidine synthase has a wide distribution among plants, although it is functionally expressed in a small group of taxa producing monoterpene indole alkaloids (see arrow in Fig. 7.17b). Related genes occur in animals and... 

The largest group of alkaloids is the monoterpene indole alkaloids, distributed in the Apocynaceae (mutual exclusion with cardenolides) and in the... 

Strictosidine is produced, stereospecifically, from tryptamine and secologanin by strictosidine synthase, isolated from several species producing monoterpene indole alkaloids. The enzyme was cloned and can be expressed in large quantity (Fig. 37). 

Several monoterpene-indole alkaloids are known in which 3-hydroxylation of the indole system has been followed by cyclisation on to the a-position [e.g., (64)]. 

Adina cordifolia has yielded a pair of jS-carboline acids, cordifoline" " (43) and adifoline (44), which are closely related to the vincosides in structural type. In both compounds the carboxy-group of precursor tryptophan is retained very few monoterpene indole alkaloids have been obtained which do still retain this feature, though of course, classical methods of alkaloid isolation would automatically lose such compounds in discarded acidic fractions. 

Sri Lankan plants of the families Apocynaceae and Rubiaceae are rich sources of monoterpene indole alkaloids. A number of plants with claims of medicinal uses have been investigated, and a variety of alkaloids isolated. To date over 100 indole alkaloids have been isolated from Sri Lankan plants, about one-fourth of which are new records. Several alkaloids have been evaluated for their biological activities. However, the majority of... 

The aerial parts of Melodinus celastroides (Apocynaceae), as well as yielding several monoterpene indole alkaloids, including tabersonine (110),... 

The occurrence of venoterpine (12) in the Apocynaceae (1) has substantially broadened, although the artifactual nature in certain instances is clear. Venoterpine (12) was isolated from Striga hermonteca, its first isolation from the family Scrophulariaceae (164), and also from the aerial parts of Vinca major (Apocynaceae) together with several monoterpene indole alkaloids (165). The same alkaloid ([ ]D +25°) was obtained from an... 

If we look beyond the cleavage of the cyclopentane ring, there is an analogous alkaloid. Although not a simple monoterpene alkaloid, but rather a monoterpene indole alkaloid, deppeaninol (381) from Deppea blumena-... 

The Aspidosperma alkaloids are a group of more than 100 monomeric and dimeric monoterpene indole alkaloids with aspidospermidine (228) representing a key member of the class and sometimes considered to be the parent [68]. Numerous total syntheses of this pentacyclic compound have been reported. Our own contributions in the area were prompted by the discovery of a new method for preparing indoles via a palladium-catalysed Ullmann cross-coupling reaction that proceeds especially efficiently at close to room temperature [69] and which we felt could serve as the centrepiece in developing a new synthesis of compound 228 and, in the longer term, syntheses of dimeric members of the indole alkaloid class such as the clinically significant alkaloids vinblastine and vincristine. 

Peduncularine was obtained from Aristotelia peduncularis (Labill.) Hook f. by Bick et al who postulated an indole-pyrrolizidine structure (44) for this alkaloid. On the basis of more extensive spectroscopic studies (including C n.m.r. spectroscopic data) and degradative work, a revised structure (45) has been proposed by Ros et al which shows that peduncularine belongs to the class of monoterpene indole alkaloids, and has no connection with pyrrolizidine alkaloids. 

Huang X, Li Y, Su YF, Chai X, Yan SL. Monoterpene indole alkaloids and mono-terpene diglycosides from the roots of Triosteum pinnafitidum. Phytochem Lett 2014 7 30-4. 

Kerber VA, Passos CS, Verli H, Fett-Neto AG, Quirion JP, Henriques AT. Psychol-latine, a glucosidic monoterpene indole alkaloid from Psychotria umbellate. J Nat Prod 2008 71(4) 697-700. 

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