Colchicum ritchii

Two demethyl congeners of speciosine (1) were found in Colchicum ritchii from southern Jordan (4). The structures of these alkaloids, 2-demethylspeciosine (2), named speciocolchine, and 3-demethylspeciosine (3), named specioritchine, were elucidated by mass and H-NMR spectro-... 

Colchicum ritchii from southern Jordan afforded, on extraction of the bulbs and removal of the alkaloids, three nonnitrogenous compounds named colchicone (7), 3-demethylcolchicone (8), and comigerone (9) (12). Because of their close chemical relationship with colchicinoids they are discussed here and are listed in Table I. The structures of these ketones were elucidated mainly on the basis of H-NMR and MS analysis, as well... 

Colchicum autumnale 17). With the isolation of monophenol androbiphe-nyline (13) and the diphenol colchibiphenyline (14) from Colchicum ritchii from southern Jordan (72), two more representatives of this group of alkaloids became available. 

To the best of our knowledge few natural (-)-allocolchicinoids have been reported. As mentioned above, natural (-)-allocolchicine 1 was isolated from C. autumnale [3,4] and C. kesselringii [5]. 3-Demethyl-allocolchicine 6, identified previously as the methyl ester of 2-demethylcolchicinic acid, was also isolated from the latter plant [5], Other natural allocolchicinoids, also named dibenzocycloheptylamines, have been reported. Colchibiphenyline 7 was isolated from Colchicum ritchii R. Br. [28] and (—)-androbiphenyline 8 from Androcymbium palaestinum (Boiss.) Bak. [29], C. ritchii [28] and Colchicum decaisnei Boiss. [30]. The latter plant also produces (-)-jerusalemine 9, (-)-salimine and (-)-suhailamine [30], though the exact structure of salimine was later questioned [31] and suhailamine had a reported structure identical to that of allocolchicine. 

Of the simple phenethylisoquinoline alkaloids dysoxyline (8), (5)-(-t-)-homolaudanosine (9), and (-)-isoautumnaline (10), 8 and 9 were isolated from Dysoxylum lenticellare Gillespie (5). Alkaloid 10 was isolated from Colchicum ritchii R.B. (4). 

Colchicum ritchii R. Br. Israel Corms, whole leafy plant... 

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