Lophocereus schottii

Schottenol (sterol) Lophocereus schottii (Senita cactus) [Precursor for fruit fly... 

In agreement with the results obtained in Lophocereus schottii on the origin of the C5 unit (C-1,T,2, 3, 4 ) in lophocerine (62), a specific incorporation of [3, 4- C]mevalonic acid and [2- " C]leucine was obtained into this alkaloid in Pachycereus marginatus. Degradation revealed a labelling pattern consistent with an equal distribution between C-T and C-4 plus C-3 from the experiment... 

Lophocereine (5), a related compound with a five-carbon unit inserted into the nitrogen-containing ring, is found in another cactus species, Lophocereus schottii. The usual carbonyl precursor probably is 4-methyl-2-oxopentanoic acid (6), an entity that probably arises by transamination of leucine (Geissman and Grout, 1969) (Fig. 32.2). However, feed-... 

In a separate series of experiments, working with intact Lophocereus schottii (Engelm.) Britt. Rose plants, it was demonstrated again by means of [ C]-labeling that the five-carbon unit in lophocerine probably arises independently from both leucine and mevalonic acid by the pathways indicated below. In this instance, no a-keto acid is involved in the Mannich cyclization. ... 

The alkaloids of the sinita cactus Lophocereus schottii and other Lophocereus species are unique in having an isobutyl substituent at carbon-1. These plants mainly contain the trimeric pilocereine, but the monomeric lophocerine has also been isolated (Djerassi et al. 1954). 

O Donovan DG, Barry E (1974) Biosynthesis of lophocerine in Lophocereus schottii, part II. J Chem Soc Perkin Trans 1. 2528-2529... 

Villotti, "The Neutral Constituents of the Cactus Lophocereus schottii," J. Amer. Chem. Soc. 80 6284 (1958). 

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