H. antidysenterica

A new alkaloid, holacetine (la), has been isolated in 0.04% yield from the root bark of Holarrhena antidysenterica, together with the known component cones-sine.1 Acetylation of holacetine gave an O-acetyl derivative (lb), vigorous acid-catalysed hydrolysis of which yielded the (20S)-20-amino-pregnane (lc). The identity of the latter, and hence of holacetine, was established by its conversion via standard methods into the known alkaloid funtumafrine C (2), and by its preparation from (20S)-3/3-hydroxypregn-5-ene-20-carboxylic acid.1 Conessine has been identified in tissue cultures of H. antidysenterica.2... 

A-Methylholarrhimine (LXXV) and 20-A methylholarrhimine (LXXVI) were found in the bark of H. antidysenterica by Tschesche and... 

This alkaloid was isolated as a chromatographically homogeneous substance (mp 95°-100° [a]]) +27° in EtOH), from the, bark of H. antidysenterica (77). Although crystalline, it resisted all attempts at recrystallization from a variety of solvents. Its structure was indicated by mass spectrometry showing a fragmentation pattern characteristic of the A -methylpyrrolidine moiety of the conanine type (peaks at m/e 71, M-15) and of a primary amino group in position 3 (peak at m/e 56). 

This alkaloid was isolated from the mixture of methylated alkaloids from the bark of H. antidysenterica (66, 67). It also occurs in the bark as a natural alkaloid (67). 

This base was isolated from the methylated alkaloid mixture from the bark of H. antidysenterica and proved to be identical with the minor product of hydrogenation of conkuressine (CXVI). Its presence in the nonmethylated alkaloid mixture was evidenced by thin-layer chromatography but the pure alkaloid could not be isolated (67). 

The presence of this base in the bark of H. antidysenterica was indicated by chromatographic evidence but the alkaloid could not be isolated in pure condition (88). 

Holonamine was isolated from the bark of H. antidysenterica from a fraction of sparingly soluble perchlorates 88). 

It is pertinent to note that the two groups are mutually related by common types. In the one case kurcholessine, which contains a methyl group in position 4, was isolated from H. antidysenterica in the other, Voticky and Tomko demonstrated the presence of the simple pregnane derivative irehine in B. sempervirens (51). The occurrence of such anomalous types may indicate the operation of aberrant biogenetic pathways in some species. 

Steroidal alkaloids have been encountered only in one Malaysian species, viz., Hoiarrhena curlisii, from which holacurtine (36), the first aminoglycosteroid was obtained [45]. Previous studies of African and Indian Hoiarrhena showed that these plants provided mainly steroidal alkaloids of the aminopregnane-type [46-48]. The Indian species H antidysenterica in particular has received considerable attention since the plant has a long history of being used in the treatment of dysentery [49,50]. A second study of the Malaysian H. curlisii was prompted by the observation that the chloroform and ethanol extracts of the leaves showed significant leishmanicidal activity which was subsequently traced lo the basic fraction derived from these extracts. Further fractionation led to the isolation of several aminoglycosteroids, holacurtine... 

The extracts of the plants of the genus Holarrhena have been used in the Ayurvedic medicine for over 1500 years in the Indian subcontinent for the treatment of parasitic infections. An important plant of this class is H. antidysenterica, whose bark has been used to treat amoebic dysentery in man. The extract of the bark of this plant, called kurchi, conessi or telicherry bark, contains several alkaloids of which the major one is conessine (8) [32,33]. This alkaloid has been used in the treatment of intestinal and extraintestinal amoebiasis in humans [34,35]. However, neither conessine nor its structural analogues find use in the modern therapy of human amoebiasis [36]. 

Holantosine-C (30), the a-L-glycoside of anhydro-holantogenin and of a new amino-sugar, L-holantosamine, 4-amino-4-deoxy-L-oleandrose, has been isolated from Indian H. antidysenterica ... 

The researches in this genus prior to 1918 are adequately reviewed by Ulrici (78), who isolated his conessine, C24H40N2, from H. africana A. DC. and showed that it was identical with the conessine (wrightine) already reported from H. antidysenterica Wall. These results were shortly verified... 

Both 1-hydroxy-11-methoxy- (24) and 11-hydroxy-1-methoxycanthin-6-one (25) have been isolated from the wood of B. antidysenterica (26, 47). In addition, 24 has been isolated from its root bark (47) and 25 from Soulamea pancheri (28). The UV spectrum of 24 shows a bathochromic shift on addition of alkali, and its mass spectrum shows the molecular ion at mlz 266 (M, 100%). These facts support the supposition that 24 is a canthin-6-one alkaloid which has a hydroxyl and a methoxyl substituent. Since the H-NMR spectrum shows aromatic proton signals, a pair of vicinal protons at H-4 and H-5, a singlet at H-2, and three protons from H-8 through H-10, it is assumed that this compound is either 24 or 25. The H-NMR spectrum of 24 is not the same as that of 25, and irradiation of... 

Repeated preparative HPLC of Ae B. antidysenterica extract [11] gave bruceanol-G (20) and -H (21). Both were colorless needles. Bruceanol-G (20) and -//(21) were evaluated against three cancer cell lines, SK-MEL-5 (melanoma), COLO-205 (colon cancer), and KB (nasopharynx carcinoma). 

Jokela and Lounasmaa presented and C-NMR exact spectral data for seven types of ajmaline-type alkaloids from various species of the Dogbane family. These alkaloids are as follows ajmaline, 17-O-acetylajmaline, iso-ajmaline, isosandwichine, rauflorine, vincamajine, and vincamedine. Four steroidal alkaloids (conessine, holadysenterine, isoconessimine, and kurchessine) were found in the stem bark of Holarrhena antidysenterica Eleven indole alkaloids were isolated from the stem bark of Kopsia hainanensis Tsiang, which is a species of Kopsia, endemic in China. They are (—)-kopsinine, (—)-kopsinnic acid, (—)-kopsinoline, kopsinilam, kopsanome, (-h)-5,22-dioxokopsane, ebumamenine, (-i-)-ebumamine, (—)-isoebumamine, (-i-)-tubotaiwine, and (-i-)-kopsoffine. Moreover, from... 

Imamura K, Fukamiya N, Nakamura M, Okano M, Tagahara K, Lee KH (1995) Bruceanols G and H, cytotoxic quassinoids from Brucea antidysenterica. J Nat Prod 58 1915-1919... 

In 1858 Haines 1 isolated from the bark of Holarrhena (Wrightia) antidysenterica Wall., known in India as kurchi, the alkaloid conessine. It was prepared from the seeds of the same plant by Stenhouse, who named it wrightine, and by Warnecke, in a crystalline condition from the same source. It was also obtained by Polstorlf and Schirmer from the African species H. africana D.C., by Pyman from H. congolensis Stapf., together with a second alkaloid, holarrhenine, by Henry and Brown from H. Wulfsbergii, and by Siddiqui et from H. febrifuga Klotsch. 

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