L-Methoxycanthin-6-one

The root bark of Ailanthus altissima Swingle contains the known alkaloids canthin-6-one (22), l-methoxycanthin-6-one, canthin-6-one A-oxide, and 1-acetyl-4-methoxy-/ -carboline, together with three new alkaloids, identified as 1-methoxy-canthin-6-one A-oxide, l-(2-hydroxyethyl)-4-methoxy-/ -carboline, and 1(1,2-dihydroxyethyl)-4-methoxy-/ -carboline.21... 

Hagen TG, Narayanan K, Names J, Cook JM (1989) DDQ oxidations in the indole area. Synthesis of 4-alkoxy-beta-carbolines including the natural products crenatine and l-methoxycanthin-6-one. J Org Chem 54 2170-2178 Hajos ZG, Parrish DR (1974) Asymmetric synthesis of bicyclic intermediates of natural product chemistry. J Org Chem 39 1615-1621... 

Similarly, Crespi-Perellino et al. (13,15), using cell cultures of A. altissima and providing L-, D-, and D,L-[w(7Av/cz c- C lryptophan as the precursor, carried out tracer experiments and proved the biosynthetic pathway to canthin-6-one alkaloids to be as follows (Scheme 7) tryptophan )8-carboline-l -propionic acid — 4,5-dihydrocanlhin-6-one (29) canthin-6-one (1)—> l-hydroxycanthin-6-one (10) l-methoxycanthin-6-one (11) —> l-methoxycanthin-6-one 3-oxide (12). In the biosynthetic pathway to canthin-6-one alkaloids, oxidation proceeds stepwise. The hydroxyl group at position 1 of canthin-6-one is methylated, and 11 is readily formed this formation is considered to be a transmethylation promoted by a specific enzyme. 

The biosynthetic route of l-methoxycanthin-6-one was studied [6], and it was clarified that the methoxyl moiety of this alkaloid was introduced after the canthin-6-one skeleton was formed. 

Some of the plants that contain canthin-6-one (30) and its relatives are used medicinally. l-Methoxycanthin-6-one... 

Cultures of Ailanthus altissima and Brucea javanica produced canthin-6-one (30) and l-methoxycanthin-6-one (31) as well as a number of minor, related alkaloids (Ellis, 1988 Liu et al., 1990). 

Ailanthus altissima is a tall deciduous tree of Chinese origin. A study of the wood extractives has revealed the presence of three alkaloids canthin-6-one, can-thin-6-one-3-oxide, and l-methoxycanthin-6-one (118). Another member of the same family, Simarouba amara, contains 5-hydroxycanthine-6-one (93). The root bark of Ailanthus excelsa contains four canthine derivatives canthin-6-one, 1 -methoxycanthin-6-one, 5-methoxycanthin-6-one, and 8-hydroxanthin-6-one (27). 

---