Showing papers on "Indole alkaloid published in 1999"

Highly Efficient, Enantioselective Total Synthesis of the Active Anti-Influenza A Virus Indole Alkaloid Hirsutine and Related Compounds by Domino Reactions.

Abstract: A very short reaction sequence consisting of a domino Knoevenagel/hetero-Diels-Alder reaction with subsequent solvolysis and hydrogenation, provides the indole alkaloid hirsutine, which greatly inhibits the growth of influenza A viruses, and related compounds in enantiomerically pure form (see reaction scheme). The facial differentiation of the cycloaddition can be reversed by simple variation of the substituents on the indole nitrogen atom (H/tBuOCO). Cbz=benzyloxycarbonyl.

Induction of alkaloid diversity in hybrid plant cell cultures

Abstract: The treatment of Rauwolfia serpentina x Rhazya stricta somatic hybrid cell suspension culture with 100 μM of methyl jasmonate led to a general increase in indole alkaloid content and to qualitative changes in the alkaloid pattern. The content of Six alkaloids were investigated with respect to their content in both the cell biomass and nutrition medium. Intracellular 17-O-acetyl-norajmaline content on the 5th day after treatment had increased about 40-fold compared with the control culture. The respective concentrations of the other alkaloids increased by a factor of two to five. In total 26 indole alkaloids were identified in extracts of the methyl jasmonate-treated culture by TLC, UV, MS and NMR data and comparison with reference alkaloids. The identification of macrophylline, yohimbine oxindole and yohimbine pseudoindoxyl has not been reported before in Rauwolfia serpentina or Rhazya stricta plants nor in cell cultures derived from these plants.

Absolute Configuration of the Indole Alkaloid (‐)‐Mehranine Hydrobromide

Abstract: The structure including the absolute configuration of the indole alkaloid (-)-mehranine hydrobromide (1·HBr) has been assigned by X-ray analysis. This result gave the possibility to assign the absolute configurations of some related alkaloids

Dippinine A, A New Alkaloid of the Chippiinetype From A Malayan Tabernaemontana

Abstract: A new indole alkaloid, dippinine A, belonging to the chippiine group was obtained from the leaf extract of Tabenaemontana corymbosa and its structure established by spectral analysis.

Synthesis of the ABCD-Rings of the Insecticidal Indole Alkaloid Nodulisporic Acid.

Abstract: Lewis acid mediated cyclization of the aldehyde 7 leads to 8, 9 and 10, of which 10 contains the structural and stereochemical elements of the ABC-rings of nodulisporic acid 1.

Synthesis of an analogue of the naturally occuring aristotelia indole alkaloid, fruticosoline

Abstract: A synthesis of an analogue of the rare Aristotelia indole alkaloids is reported. The monoterpene, Pule gone, 1 on nitromethylation give nitromethylpulegone, 2, which on reduction with LiAlfu and as well as with NaBfu yield the compounds 3, 4 and S. The amino-alcoholS is condensed with indolyloxalyl chloride 6 to furnish the a-ketoamide 7, which is converted to the corresponding monoterpenoid indole alkaloid 8, an analogue of fruticosoline 9.

Genetic Transformation of Catharanthus roseus (Periwinkle)

Abstract: Catharanthus roseus (L.) G. Don (= Vinca rosea L.), the Madagascar periwinkle, is a pantropical erect subshrub, belonging to the family Apocynaceae. The plant accumulates more than 100 indole alkaloids, mainly the monomeric alkaloids ajmalicine, serpentine, vindoline, and catharanthine. Ajmalicine is an antihypertensive drug used in the treatment of circulatory diseases. Vindoline and catharanthine are the precursors of dimeric alkaloids, such as vinblastine and vincristine, the importance of which in the treatment of acute leukemia was established in the 1960s (Van Tellingen et al. 1992). Indeed, these two alkaloids were the first plant products to be approved by the FDA for cancer treatment (Noble 1990). They accumulate in aerial parts of the plant but only in very low amounts; thus they are very costly.

Tronoharine, a Novel Hexacyclic Indole Alkaloid from a Malayan Tabernaemontana.

Abstract: A novel hexacylic indole alkaloid, tronoharine, was obtained from the stem-bark extract of Tabernaemontana corymbosa and its structure elucidated by spectral analysis.

First Synthesis of Hunterioside, a Novel Disaccharide Carrying Monoterpenoid Indole Alkaloid, by Assembly of Three Components, Tryptamine, Secologanin, and a Newly Developed Glucosyl Donor.

Abstract: The novel structure of hunterioside, the first example of monoterpenoid indole alkaloids carrying a disaccharide, was confirmed by chemical synthesis starting from tryptamine, secologanin, and a newly-developed gulucosyl donor, which selectively gives α-gluco type glycosidic linkage in the reaction with a secologanin derivative.

Indole alkaloid type compound 0089-D

Abstract: The present invention relates to compound 0089-D having excellent antitumor activity and antimicrobial activity, represented by the general formula (I): ##STR1## or pharmaceutically acceptable salts thereof.