Drupacine

Pest Manag Sci. 2013 Sep;69(9):1026-33.

Nematotoxicity of drupacine and a Cephalotaxus alkaloid preparation against the plant-parasitic nematodes Meloidogyne incognita and Bursaphelenchus xylophilus.[Pubmed: 23785026 ]

METHODS AND RESULTS:
Species of Cephalotaxus (the plum yews) produce nematotoxic compounds of unknown identity. Consequently, bioassay-guided fractionation was employed to identify the compound(s) in Cephalotaxus fortunei twigs and leaves with activity against plant-parasitic nematodes. A crude alkaloid extract, particularly Drupacine, was responsible for much of the nematotoxicity. The ED50 of Drupacine for Bursaphelenchus xylophilus was 27.1 μg mL⁻1, and for Meloidogyne incognita it was 76.3 μg mL⁻1. Immersion of M. incognita eggs in 1.0 mg mL⁻1 crude alkaloid extract (the highest tested concentration) reduced hatch by 36%; immersion of second-stage juveniles (J2) resulted in 72-98% immobility. Crude alkaloid extract and Drupacine suppressed protease activity in extracts of the microbivorous nematode Panagrellus redivivus by 50% and 80%, respectively. Application of 0.02-0.5 mg mL⁻1 crude alkaloid extract to soil with M. incognita inoculum did not significantly reduce pepper plant shoot length or weight, compared with nematode-inoculated, water-treated controls, but the number of eggs and J2 per root system respectively decreased by 69% and 73% at 0.5 mg mL⁻1.
CONCLUSIONS:
Drupacine and a crude alkaloid extract suppress nematode hatch, activity of mixed life stages, and population numbers on plant roots. This is the first demonstration of nematotoxicity of crude Cephalotaxus alkaloids and Drupacine.

Yao Xue Xue Bao. 2003 Dec;38(12):919-23.

Synthesis and antitumor activity of the derivatives of cephalotaxine and drupacine.[Pubmed: 15040085]

To make full use of cephalotaxus plant resources and search for antitumor agents with higher activities and lower side effects.
METHODS AND RESULTS:
The C3 hydroxy groups of the cephlotaxine and Drupacine were acylated by taxol side chain and its isomers to give a series of derivatives of cephlotaxine and Drupacine. Six novel alkaloid esters were designed and synthesized. The pharmacological screening results showed that VIIIa, VIIIb, IXa and IXc exhibited significant activities on KB, HCT and Bel in vitro.
CONCLUSIONS:
Novel alkaloid esters are worthy to be intensively studied.

J Chromatogr A. 2009 May 29;1216(22):4663-7.

Completed preparative separation of alkaloids from Cephaltaxus fortunine by step-pH-gradient high-speed counter-current chromatography.[Pubmed: 19393155 ]

Cephalotaxine-type alkaloids are the anti-cancer components in twigs, leaves, roots and seeds of Cephalotaxus fortunine. It is very important to use the limited resource by finding an efficient purification technology of the alkaloids.
METHODS AND RESULTS:
Separation of cephalotaxine-type alkaloids in Cephalotaxus fortunine by step-pH-gradient high-speed counter-current chromatography (step-pH-gradient HSCCC) was studied in this paper. The step-pH-gradient HSCCC was performed on a HSCCC instrument equipped with a 400-mL column, using the upper phase of ethyl acetate-n-hexane-water, with added 0.01% trifluoroacetic acid (TFA) as stationary phase, and the lower phase of ethyl acetate-n-hexane-water, with added 2% NH(4)OH, 0.2% NH(4)OH and 0.05% TFA as mobile phase. For each separation, 800mg of extract of cephalotaxine-type alkaloids was separated to yield 9.3mg of Drupacine, 15.9mg of wilsonine, 130.4mg of cephalotaxine, 64.8mg of epi-wilsonine, 12.8mg of fortunine and 35.6mg of acetylcephalotaxine with purities 81.2%, 85.7%, 95.3%, 97.5%, 89.1% and 96.2%, respectively.
CONCLUSIONS:
The recovery of each alkaloid was more than 90%. The structures of the six alkaloids were identified by electrospray ionization mass spectrum (ESI-MS) and (1)H and (13)C NMR.