Nerine bowdenii

The availability of the enantiomeric alkaloids vittatine (284) and crinine in labeled form through separate feeding experiments with labeled 343 in Pancratium maritimum L. and Nerine bowdenii, respectively, provided experiments which indicated the absolute configuration of narciclasine. Thus, the two alkaloids were obtained from [3, 5 -3H2]-O-methylnorbelladine. Experiments with multiply labeled 343 have previously shown that no 3H loss takes place during the biosynthesis,... 

This tertiary base, containing one methoxyl and the methylenedioxy function, has been isolated from Grinum moorei (70), Nerine bowdenii (66), N. corusca (85), and N. flexwsa (85). Analytieal data provided the molecular formula Ci7HigN05. Acetylation of the alkaloid under mild conditions afforded both a mono- and a diacetyl derivative. The results of this acetylation and the similarity in infrared spectra of crinamidine and powelline led Boit and Ehmke to consider the alkaloid to be a hydroxypowelline. Such a structure is inadmissible for several reasons. 

Results of experiments with labelled crinine (86), and less conclusively with oxovittatine, indicate that the two naturally occurring enantiomeric series, represented in Figure 9 by crinine (86) and vittatine (39), are not interconvertible in Nerine bowdenii (127). 

Narcissus tazetta var.florepleno and var. panizzianus Nerine bowdenii... 

Bowdensine (CXXXIV R, Ri = CH3CO) and its 0,0-deacetyl derivative have been isolated from Nerine bowdenii (21). Bowdensine has not been isolated in crystalline form but is concentrated in the crude alkaloid fraction forming chloroform-soluble hydrochlorides. Bowdensine ([aJu + 17.3° in CHCI3) forms a methiodide (mp 284°-285° decomp. ... 

The negative incorporations must be interpreted with caution, since solubility aspects and transport of the radioactive precursors to the site of biosynthesis may be extremely important 45, 47, 166). The last compound cited in Table III was incorporated into galantha-mine with no randomization (presumably via isovanillin), yet isovanillin was not utilized for alkaloid formation in either the Narcissus Deanna Durbin or in Nerine bowdenii 45, 47). Phenylalanine, an established precursor of the C-6—C-1 fragment of the alkaloids when injected into the leaves, flower stems, or bulbs, is not incorporated into alkaloids when introduced via root absorption from a hydroponic solution containing the radioactive amino acid 166). 

Mann et al. isolated a cateehol-O-methyltransferase from the Amaryllidaceae Nerine bowdenii bulbs that catalyzed the highly regiospeeifie methylation of norbelladine at the para position at a yield of more than 90% but it also methylated a wide range of catechol substrates [73], Additionally, protein extracts from leaves of L. vemum showed specific activity with regiospecificities favoring the 4 position of norbelladine over the 3 position in a 18 1 ratio [28] and transcript sequences for OMTs were deteeted in the transcriptome of L. radiata [41]. 

Cahlikova L, Zavadil S, Macakova K, Valterova I, Kulhankova A, Hostalkova A, Kunes J, Opletal L (2011) Isolation and cholinesterase activity of Amaryllidaceae alkaloids liom Nerine bowdenii. Nat Prod Commun 6 1827... 

Boit, H.-G., and H. Ehmke Alkaloids from Nerine bowdenii, Crinumpowellii, Amaryllis belladonna, and Pancratium maritimus. Chem. Ber. 89, 2093 (1956). 

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