Secologanin derivative

Treatment of the sodium salt of malondialdehyde with the monoacetal 3 (5°C, 48 hr), followed by the addition of (Z)- or ( )-l-methoxy-l-butene provides 4 and 5, respectively. The secologanin derivative 5 possesses the relative configuration typical of the secoiridoids.97... 

As in acidic hydrolysis, secologanin (1) and 7-substituted bakankosine derivatives (e. g. 13) underwent fragmentation (see later), and sweroside (31a) was destroyed without giving a well defined product, Af-methyl bakankosine (17a) and its dihydro derivative (17b) were selected as model compounds for investigation of the acidic deglucosylation of secologanin derivatives. In the stable educts, C-l and C-ll had been inactivated by lactamization [24]. 

The synthesis of dihydromeroquinene derivatives from secologanin (268) affords a new and convenient stereoconservative synthesis of the Cinchona alkaloids. Two routes were developed (Scheme 44) both resulted in the conservation of the easily epimerised centre at C-2 in the secologanin derivatives. The first route resulted in the formation of dihydromeroquinene (cincholoipon) hydrochloride (269), which was identified by conversion into methyl N-benzoyldihydromeroquinenate (270) the other afforded methyl dihydro-meroquinenate (271), which has previously been converted into quinine. 

Monoterpenoid indole alkaloids (MIAs) are derived from tryptophan metabolism. MIAs are one of the most structurally diverse class of compounds with over 2,000 structures. They are mostly found in the Apocynaceae, Loganiaceae, and Rubiaceae family of plants [12]. Similar to BIA biosynthesis, the committed step of MIA biosynthesis begins with the condensation of tryptamine (derived from tryptophan) and secologanin (derived from terpene biosynthesis) to form strictosidine... 

Yohimbine (104), also from the bark of C.johimbe K Schum. and from the roots of R. serpentina (1. ) Benth. has a folk history (unsubstantiated) of use as an aphrodisiac. Its use has been confirmed experimentally as a local anesthetic, with occasional employment for rehef ia angiaa pectoris and arteriosclerosis, but is frequently contraindicated by its undesired renal effects. Yohimbine and some of its derivatives have been reported as hahuciaogenic (70). In addition, its pattern of pharmacological activities ia a variety of animal models is so broad that its general use is avoided. All ten carbon atoms of secologanin (102) as well as the entire skeleton of tryptamine (98, R = H) are clearly seen as iatact portions of this alkaloid. 

Contin, A. et al.. The iridoid glucoside secologanin is derived from the novel triose phosphate/pyruvate pathway in a Catharantus roseus cell culture, FEES Lett., 434, 413, 1998. 

Indole alkaloids from Tabernaemontana plants are all biogenetically derived from tryptophan (tryptamine) and secologanine, which constitute the indole and terpenic portions, respectively, and can be classified into nine main types depending on the structural characteristics of their skeleton (Fig. 1). 

Leonard, J. 1999. Recent progress in the chemistry of monoterpenoid alkaloids derived from secologanin. Nature Product Reports, 16 319-338. 

Systematic nomenclature of vitamin D derivatives utilizes the obvious relationship to steroids, and the term seco (ring opened) is incorporated into the root name (compare secologanin as a... 

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