Kurchi alkaloids

Lettocine, Cj7H2502N, is a pale brown microcrystalline powder, m.p. 350-2° it yields a crystalline hydriodide, B. HI, m.p. 256° dec.) picrate, m.p. 198°, and is recovered unchanged from boiling acetic anhydride. Bertho suggested that it may be a condensed form of a Kurchi alkaloid (p. 742). 

Addendum. In a recent paper Bertho et al. have described a new process for the isolation of kurchi alkaloids. From the final residue a new base, C23H34N2, m.p. 129 5°, was isolated as the carbonate, m.p. 91° it provides the following salts B, 2HI, 2H2O, dec.) 174° B, 2HCIO4, 2.5H2O, m.p. 283°, and a mono-acetyl derivative, m.p. 254°. In a second paper Bertho, Schonberger and Kaltenbom describe further products obtained in the oxidation of conessine by chromic acid and by potassium permanganate. ... 

Kurchi bark is principally used in India as a remedy for amoebic dysentery, and in recent years there has been a revival of medical interest in the drug in this eonneetion. It is generally used in the form of a bark extract but, in imitation of emetine bismuth iodide, kurchi bismuth iodide, consisting of the bismuth iodides of the mixed alkaloids of the bark, has also been used. On the pharmaceutical side Datta and Bal have studied the pharmacognosy of the bark and a method of alkaloidal assay has been devised by Schroff and Dhir, who have also described a process for the preparation of kurchi bismuth iodide, a product for which they, and also Mukherjee and Dutta, have provided methods of assay. 

This alkaloid (LXVII) is isomeric with kurchiline and shows close similarity to it in spectral data except for those pertaining to the ketone group. The position of the carbonyl band in the IR-spectrum (1748 cm i) demonstrated the keto group to be a part of a five-membered ring. This fact, in conjunction with strong negative optical rotation shown by the base, led to location of the ketone group in position 16. Both kurchi-... 

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]. 

Labler, Sorm, Coif. Czech. Chem. Commun. 28, 2345 (1963). Synthesis by methylation of kurchamine Tschesche, Wiensz, Ber. 91t 1504 (1958)- Structure Tables Somi, he. cit, Possible identity with sarcodinine from Sara-cococo pruniformis LindU Euphorbiaeeae Chatterjee et oi> Tetrahedron Leiiers 1965, 67. Related alkaloids, kurchiline, kurchiphytline, kurchiphyltamine7 from Kurchi Leaves Janot et ai, Bull. Soc. Chim. France 1964, 2158. 

LIblbr and Cern [105, 106] have worked in detail on the Kurchi-or Holarrhena alkaloids, including conessine which contains a pyrrolidine ring, and on their derivatives and various aminopregnanes and -cholestanes. Benzene or diethyl ether, saturated with concentrated aqueous ammonium hydroxide, were satisfactory solvents used on silica gel containing gypsum. The systematic study yielded informative data about the relation of structure and chromatographic behaviom this has been already discussed in section IV. 

Steroidal alkaloids of the group of pseudoalkaloids have been found in the bark and fruit of Holarrhena spp. (Apocynaceae), distributed in Asia and Africa (23). They are sometimes referred to as Kurchi alkaloids (80). 

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. 

Irani has isolated from an alcoholic extract of kurchi seeds a crystalline gluco-alkaloid, which froths at 65°, melts at 200° (dec.), forms a benzoyl derivative and gjves a dark-green colour with ferric chloride. When a saturated solution of picric acid is added to an aqueous solution of the gluco-idkaloid hydrolysis occurs, the products t ing conessine picrate, a second piorate, m.p. 113-6°, and galactose. 

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