Haplophyton

Haplophyton cimicidum A. IX., Ang., a Mexican shrub, La hierbe de la cucaracha , used since the Aztec as an anticdcroach/insectic idal... 

O-Methylebumamine (CCCXL-A), found in Haplophyton cimicidum, was identified by loss of methanol to eburnamenine (CCCXLIII) and chromic acid oxidation to eburnamonine (CCCXLII, 113b). 

The Mexican cockroach plant, Haplophyton cimicidum A.DC. (Apocyanaceae), was first investigated by Snyder and his collaborators, who isolated two insecticidal alkaloids, haplophytine and cimicidine (1-4). Both alkaloids were reported to be toxic to a wide variety of insects, but most of the toxicity of the plant appeared to be owing to the haplophytine content (1). 

Haplophyton cimicidum thus joins the interesting group of plants which produce both the aspidospermine and the biogenetically intimately related eburnamine types of alkaloids. 

Since oxidized derivatives of secodine appear to be involved as late intermediates in the biosynthesis of the aspidospermidine and pseudoas-pidospermidine alkaloids, it is logical to begin with those secodine derivatives that have been found to occur naturally. Tetrahydrosecodine (1) occurs in the root bark of Aspidosperma marcgravianum Woodson (5) and has been detected in cell-suspension cultures of Rhazya stricta Decaisne (6) its demethoxycarbonyl derivative (2) also occurs in A. marcgravianum (5), and in Haplophyton crooksii L. Benson (7,8) and the roots of R. stricta (9). The two isomeric carbonyl derivatives, 2-ethyl-3-[2-(3-acetyl-V-piperidino)ethyl]indole (3) and crooksidine (4), occur, respectively, in A. marcgravianum (5) and H. crooksii (7,8). 

Crooksidine (4), the alkaloid of Haplophyton crooksii, has been synthesized by two groups of workers. The first of these (272) consists of a very straightforward route in which condensation of 2-ethyltryptamine with methyl 4-formylhexanoate gave the dihydropyridone derivative 425. Reduction followed by oxidation then gave crooksidine (4) (Scheme 3S). 

This insecticidal alkaloid (99, C3,H4q07N4) has been isolated from Haplophyton cimicidwn A.DC. (Apocynaceae). It contains two basic nitrogens and a phenolic hydroxy-group. Acid-catalysed cleavage leads to the base (100), whose structure follows from spectral data, and in particular from a comparison of its mass... 

Cimicine and cimicidine were reported from Haplophyton cimicidum A. DC. by Cava et al. in 1963 (55), and some of their chemistry has been described earlier in this series (Volume VIII, p. 451). More recently, a paper (59) has appeared on these alkaloids including data leading to the stereoformulas 110 and 111 for cimicine and cimicidine, respectively. 

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