Haplophyllum foliosum

A somewhat more complex 4-methoxy-2-quinolone is the alkaloid foliosidine (VIII) (inp 141°-142°) from Haplophyllum foliosum Vved. (see Section VI). The 2,3-dihydroxyisopentyloxy side chain, also found in evoxine and maculosine, was shown to be present by periodic acid oxidation to acetone and an optically inactive aldehyde. 

An introductory chapter on the furoquinoline alkaloids with excellent coverage and leading references to the literature has been published as part of a general volume on alkaloids.1 A detailed chromatographic analysis of quinoline alkaloids in liquid-liquid systems with buffered aqueous phase and a polarographic method for the determination of dubinidine from Haplophyllum foliosum have been reported.2 From a pH-R f relationship, the optimum conditions for extraction and chromatography were developed.20... 

Foliosidine acetonide (2 R1 4- R2 = Me2C), isolated from Haplophyllum foliosum, may be an artifact.6 It was hydrolysed to foliosidine (2 R1 = R2 = H) which has also been isolated from the same species. Treatment of an acetone solution of the latter with sulphuric acid afforded foliosidine acetonide. The isolation of dictamnine and skimmianine from Haplophyllum suaveolens is of chemotaxonomic interest.7 Previously, kokusaginine (1 R1 = R2 = OMe, R3 = H) and khaplofoline (6) had been obtained from this species.12 The... 

Methoxy-l-methyl-2-quinolone (1) was isolated from Hesperethusa crenulata M. Roem. (12) and from the wood of Fagara boninensis (13). The alkaloid folimine from Haplophyllum foliosum Vved. (14) was identified as 4,8-dimethoxy-l-methyl-2-quinolone (2), which had been obtained earlier during the degradation of foliosine (Volume IX, p. 225). Folifidine from H. dubium Eug. Kor (15) and from H. foliosum (16) is the 8-hydroxy-2-quinolone 3. 

Alkaloids of this type have been described previously, and during the last ten years new sources of known alkaloids have been recorded. Thus, the simplest member of the group 309, previously obtained only from Balfourodendron riedelianum, has now been isolated from Haplophyllum foliosum (164). Graveoline (rutamine) (310), a characteristic alkaloid of... 

Folimidine was obtained from Haplophyllum foliosum and is assumed to have structure 313 on the basis of spectroscopic studies on the alkaloid and its O-methyl derivative (210). 

The Table summarizes recent isolation and structural elucidation work on quinoline and furoquinoline alkaloids of plant origin. The structure of folisine (4) from Haplophyllum foliosum was confirmed by synthesis. Heating the methiodide of dubinidine (11) yielded folisine. The alkaloid distribution in H. suaveolens was extensively examined in leaf, stem, fruit with seeds, and root kokusaginine (1 R = = OMe, R = H) was found to be the major component in all... 

Haplophyllum foliosum [16], Myrtopsis sellingii [44], Zanthoxylum integrifoliolum [16] ... 

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