Catharanthus roseus vindoline from

Salutaridinol 7-0-acetyltransferase catalyzes the conversion of the phenanthrene alkaloid salutaridinol to salutaridinol-7-Oacetate, the immediate precursor of thebaine along the morphine biosynthetic pathway in P. somniferum (Fig. 10.7).26 Acetyl CoA-dependent acetyltransferases have an important role in plant alkaloid metabolism. They are involved in the synthesis of monoterpenoid indole alkaloids in medicinal plant species such as Rauwolfia serpentina. In this plant, the enzyme vinorine synthase transfers an acetyl group from acetyl CoA to 16-epi-vellosimine to form vinorine. This acetyl transfer is accompanied by a concomitant skeletal rearrangement from the sarpagan- to the ajmalan-type (reviewed in2). An acetyl CoA-dependent acetyltransferase also participates in vindoline biosynthesis in Catharanthus roseus, the source of the chemotherapeutic dimeric indole alkaloid vinblastine (reviewed in2). Acetyl CoA deacetylvindoline 4-O-acetyltransferase catalyzes the last step in vindoline biosynthesis. A cDNA encoding acetyl CoA deacetylvindoline 4-0-acetyltransferase was recently successfully isolated.27... 

Leurosine (75) (Scheme 20) is the most abundant of the dimeric antitumor alkaloids isolated from Catharanthus roseus G. Don. Several species of Strep-tomyces produced a common metabolite of the alkaloid, and S. griseus (UI1158) was incubated with 400 mg of leurosine sulfate to obtain 28 mg of pure metabolite (180). The metabolite was identified as 76 primarily on the basis of its H-NMR spectrum. The mass spectrum indicated that the metabolite contained one oxygen atom more than 75. The H-NMR spectrum contained all of the aromatic proton signals of the vindoline portion of the molecule, and aromatic proton signals for the Iboga portion of the compound occurred as a doublet of doublets... 

Other examples of natural drugs may be pointed out streptozotocin (from streptomyces achromogenes), bleomycin (from streptomyces verticillus), adriamy-cin and daunomycin (from streptomyces pencetius), mitomycin C (from streptomyces caesipitosus), vincristine, vinblastine and vindoline (from catharanthus roseus or vinca rosea L.). 

Vincamine, vinblastine and vincristine are very important clinic alkaloids. They are produced naturally by plants vincamine by Vinca minor, and vinblascine and vincristine by Madagascar periwinkle Catharanthus roseus). The vindoline synthesis pathway starts with strictosidine and, via dehydrogeissoschizine, preakuammicine, stemmadenine and tabersonine, is converted to vindoline and vincristine (Figure 42). Conversion from vindoline to vinblastine is based on the NADH enzyme activity. Vinblastine and vincristine are very similar alkaloids. The difference is that vincristine has CHO connected to N, whereas vinblastine in the same situation has only CO3. This synthetic structural differences influence their activity. Vinblastine is used to treat Hodgkin s disease (a form of lymphoid cancer), while vincristine is used clinically in the treatment of children s leukaemia. Vincristine is more neurotoxic than vinblastine. 

Vindolicine (vindoline 10,10 -dimer) and fourteen bisindole alkaloids of the vinblastine group have been isolated from the aerial parts of Catharanthus ovalis.ny These include leurosine, 21 -hydroxyleurosine, vinblastine, 20 -deoxy-leurosidine, 20 -deoxyvinblastine, pleurosine, Catharine, catharinine, vincristine, and vincathicine. A new alkaloid is 21 -oxoleurosine (198), which has also been found recently in Catharanthus roseus.U8 The three remaining alkaloids are vincovaline (199) and vincovalinine (16 -desmethoxycarbonyl-leurosine), whose structures119 have now been confirmed, and vincovalicine, which has... 

Within the natural products field, the investigation of complete biosynthetic pathways at the enzyme level has been especially successful for plant alkaloids of the monoterpenoid indole alkaloid family generated from the monoterpene gluco-side secologanin and decarboxylation product of tryptophan, tryptamine [3-5]. The most comprehensive enzymatic data are now available for the alkaloids ajmalicine (raubasine) from Catharanthus roseus, and for ajmaline from Indian Rauvolfia serpentina [6] the latter alkaloid with a six-membered ring system bearing nine chiral carbon atoms. Entymatic data exsist also for vindoline, the vincaleucoblastin (VLB) precursor for which some studies on enzymatic coupling of vindoline and catharanthine exist in order to get the so-called dimeric Catharanthus indole-alkaloids VLB or vincristine [7-9] with pronounced anti-cancer activity [10, 11]. 

DE LUCA, V., BALSEVICH, J TYLER, R.T., EILERT, U PANCHUK, B.D., KURZ, W.G.W., Biosynthesis of indole alkaloids Developmental regulation of the biosynthetic pathway from tabersonine to vindoline in Catharanthus roseus. J. Plant Physiol., 1986,125, 147-156. 

DE CAROLIS, E., DE LUCA, V., Purification, characterization, and kinetic analysis of a 2-oxoglutarate-dependent dioxygenase involved in vindoline biosynthesis from Catharanthus roseus. J. Biol. Chem., 1993,268,5504-5511. 

Extensive studies to quantitate the production of indole alkaloids in Catharanthus roseus hairy root cultures have revealed that they accumulate several compounds including ajmalicine, serpentine, catharanthine, tabersonine, horhammericine, and lochnericine.27, 28 The presence of tabersonine in hairy roots has raised speculations that this intermediate in vindoline biosynthesis, together with catharanthine, is transported from this potential site of biosynthesis through the vasculature to the stem and to the leaves where tabersonine is further elaborated into vindoline within laticifers and/or idioblasts.26 However, oxidized derivatives of tabersonine, such as horhammericine and lochnericine, are present at 5 to 15 times the levels of tabersonine in hairy roots,27 and presumably this prevents their transport and/or use for vindoline biosynthesis. In this context, it would be interesting to... 

Quaternary ammonium compounds are important as osmoprotectants in times of water deficiency and cold stress, as well as being constituents of membrane phospholipids, p-Alanine and phosphoethanolamine are each methylated three times on their nitrogens to produce the products P-alanine betaine and phosphocholine, respectively (Fig. ll.l).24"27 An example of O-methylation and N-methylation occurring on the same molecule can be found in the indole alkaloid vindoline from Catharanthus roseus (Fig. 11.1) 28,29... 

A number of alkaloids with the aspidospermine skeleton occur in the genus Vinca and are dealt with in detail in Chapter 12. They include the very important base vindoline (CIII) which not only occurs as the free base in Vinca rosea (= Lochnera rosea = Catharanthus roseus) but also as part of the dimeric alkaloids vinblastine (vincaleucoblastine) and leurosine, whereas the Aa-formyl analog, CIV, forms part of the dimeric alkaloid leurocristine (5, 72a). These dimeric alkaloids have been used successfully for the treatment of certain forms of cancer in man (5). Vindolinine (CVI) has also been isolated from V. rosea and its dihydro-decarbomethoxy derivative, tuboxenin (CVI-A), which is the parent member of the series, occurs in a Pleiocarpa species (53). ( + )-Vincadif-formine (XCIII, 6, 74) has already been mentioned as the racemic form of (— )-6,7-dihydrotabersonine (Section II, O). It has been found in V. difformis and in Rhazya stricta (51b) where the (+) form also occurs. 

Endo T, Goodbody A, Vukovic J, Misawa M. Enzymes from Catharanthus roseus cell suspension cultures fiiat couple vindoline and cafiiaranthine to form 3, 4 -anhydrovinbastine. Phytochemistry 1988 27 2147-2149. 

If the C-15, C-16 bond is oxidatively cleaved, the secodine skeleton results (the proposed progenitor of the Aspidosperma and the iboga systems) through alternative Diels-Alder type cyclizations to afford tabersonine and catharanthine. The bisindole alkaloids of Catharanthus roseus reflect the union of vindoline and catharanthine to afford anhydrovinblastine modification affords the clinically significant alkaloids, vinblastine (VLB) and vincristine (VCR Fig. 39). The alkaloids, particularly VCR, are important as anticancer agents and have led to the development of the semisynthetic derivatives vindesine and vinorelbine (Fig. 40). Synthetic approaches are available to join the monomeric precursors. The enzymatically controlled sequence of reactions from tabersonine to vindoline has been elucidated. 

This reaction has been extensively studied in the case of the chlopromazine radical (R -mediated aminopyrine (S) oxidation [41], a typical reaction for xenobiotics, as well as in the case of the vindoline radical (R -mediated catharanthine (S) oxidation [42], a key reaction in the biosynthesis of the anticancer drugs, vinblastine and vincristine, which are obtained from Catharanthus roseus. 

Terpenoid Indole Alkaloids.—Crude preparations from Catharanthus roseus seedlings and from tissue cultures have been shown to be capable of synthesizing in good yield from tryptamine (110) and secologanin (111) with added co-factors, geisso-schizine (112) and ajmalicine (113), representatives of the first major class of terpenoid indole alkaloids (Corynanthe). Geissoschizine was metabolized to ajmalicine and several other unidentified alkaloids (for reviews of biosynthesis in intact plants see ref. 106). The catabolic turnover of vindoline and catharanthine in C. roseus has been studied. ... 

Vincristine is the nonproprietary name for the alkaloid originally called leurocris-tine. It is obtained from the plant Vinca rosea Linn. (Catharanthus roseus G. Don) of the family Apocynaceae(Madagascar periwinkle). Vincristine sulfate is the 1 1 sulfate salt of vincristine. The structure of vincristine differs from that of vinblastine- only by the substituent at the anilino-nitrogen in the vindoline portion of the molecule. Thus it is des-Na-methyl-Na-formyl vinblastine. It is also known by the code numbers NSC-67571 and 372313 and is abbreviated to VCR and VCR sulfate. Elucidation of the molecular structure, stereochemistry, and absolute configuration of this compound is found in the literature ... 

Catharine, first isolated in 1961 from Catharanthus roseus, was subsequently stated, correctly, to possess an intact vindoline component.The second component has only recently been elucidated it contains an unusual enamide function, presumably derived from the oxidative fission of the piperidine ring in a velbanamine derivative. Catharine is thus closely related to vinblastine, and its complete structure, elucidated by the X-ray method, is (224). 

C46HjgN40 Mr 810.99, cryst., mp. 216°C, [alp +42 (CHCI3) a dimeric indole alkaloid from Catharanthus roseus (see Vinca alkaloids), composed of two parts vindoline and catharanthine with a 10,3 -linkage. V. is a cytostatically active trace alkaloid and is accompanied by demethylated, deformylated, and deacety-lated alkaloids. V. also occurs in other Catharanthus species such as C. ovalis. C. longifolius, C. trichophyl-lus. It is one of the most important monoterpenoid indole alkaloids. 

The products of cell culture of Catharanthus roseus are many and varied (Ellis, 1988) bisindole alkaloids and other products from cultures of this plant have been reviewed (Blasko and Cordell, 1990). Some lines fail to produce any of the alkaloids normally found in the whole plant. Ajmali-cine (7) and serpentine (8) (class 1 or Corynanthe-Xype alkaloids) often are the principal alkaloids produced in Catharanthus roseus tissue cultures (Blasko and Cordell, 1990 Ellis, 1988 Knobloch et al. 1982, Kurz et al. 1980). Taber-sonine (24) (a class 3 or Aspidosperma alkaloid) and catharanthine (10) (a class 5 or iboga alkaloid) have been found in relatively low yields in tissue cultures (DeLuca et al. 1986). Vindoline (9) (a class 3 or Aspidosperma alkaloid), a major alkaloid in Catharanthus roseus plant material, has never been found in plant tissue cultures. The pathways leading to vindoline appear to occur in the shoots of Catharanthus roseus plants, but are not known to occur in roots (DeLuca et al., 1986). 

Both vindoline (9) and catharanthine (10) are of great importance, as coupling of these two compounds (possibly via an iminium intermediate) leads to 3, 4 -anhydrovinblas-tine (57), a direct precursor to both vinblastine (57) and vincristine (56) (Fig. 34.15) (Blasko and Cordell, 1990 Stuart et al., 1978). Enzymes from cell-free systems of Catharanthus roseus have been demonstrated to carry out this coupling (Endo et al., 1988). The reaction also can be catalyzed by horseradish peroxidase (Goodbody et al, 1988) or... 

Piperine (54) and antiepilepsirine (55), piperidine alkaloids that occur in Piper species (Piperaceae), are MAOIs with greater selectivity for MAO-B [173], yet they have not been studied extensively for therapeutic potential in PD. Some Vinca alkaloids, including vincristine, vinblastine, leurosine, and vindoline from Catharanthus roseus (L.) G.Don (Apocynaceae), are reported as selective MAO-B inhibitors, but cytotoxicity limits their development as potential drug candidates for PD [174, 175] (see Sect. 6) (Scheme 42.14). 

When LEE is used, it is advisable to do either very quickly or from only a moderately alkaline aqueous solution, which was basified by sodium carbonate or ammonia. The Catharanthus alkaloids was prepared by LEE from the 75 % ethanol extract at pH 3.5, then adjusted the basic to pH 12 and finally extracted by chloroform [7]. Three major alkaloids, vinblastine and its monomeric precursors (vindoline and catharanthine), were monitored in transformed root cultures of Catharanthus roseus, after rapid sample preparation by LEE in our previous work [8]. The extraction method was the same as above. Other Catharanthus alkaloids, such as vindoline, catharanthine, and anhydrovinblastine, were prepared by LEE from the methanol extraction [9]. 

Ionic liquid-based ultrasound-assisted extraction (ILUAE) was successfully applied to the extraction of three alkaloids, vindoline, catharanthine, and vinblastine from Catharanthus roseus. Twelve ionic liquids, with different cations and anions were investigated in this work. In addition, ultrasound extraction parameters, including soak time, solid-liquid ratio, ultrasound power and time, and the number of extraction cycles, were optimized. ILUAE offered short extraction times (from 0.5 to 4 h) and remarkable efficiency. Therefore, the use of ionic hquids in the ultrasound-assisted extraction of key chemicals from medicinal plants shows great potential [12]. 

Fig. 34.3 Total ion chromatogram (a) and extracted ion chromatogram (b) of a standard mixture solution, and extracted ion chromatogram (c) of Catharanthus roseus extract by CE-MS. CE conditions capillary, 65 cm length and 50 pm i.d, buffer 20 mM s ammonium acetate aqueous with 1.5 % acetic acid, temperature room temperature, sample, 50 mbar for 5 s injection MS-conditions ESI positive, sheath gas 4 psi dry gas 6 L/min dry temperature 130 °C capillary voltage 3.5 kV sheath liquid methanol/water = 1/1, with 0.1 % acetic acid flow rate of sheath liquid 4 pL/min. Peak identification 1 vinblastine 2 catharanthine 3 vindoline (From Ref. 8)... 

Yang L, Wang H, Zu Y, Zhao C, Zhang L, Chen X, Zhang Z (2011) Ultrasound-assisted extraction of the three terpenoid indole alkaloids vindoline, catharanthine and vinblastine from Catharanthus roseus using ionic liquid aqueous solutions. Chem Eng J 172 705-712... 

Geraniol 10-hydroxylase (CYP76B6) from Catharanthus roseus is a key regulatory enzyme in the synthesis of the terpene indole alkaloid vindoline [51]. Alkaloids such as vincristine and vinblastine (derived from vindoline) are used in modem medicine as anti-neoplastic agents (Fig. 3). 

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