3198
X. Dong et al. / Bioorg. Med. Chem. Lett. 19 (2009) 3196–3198
In summary, the synthesized prenylflavonoids had been charac-
terized as agents with remarkable vasorelaxant and significant
neuroprotective effects. Some common structural features shared
in potent agents were found, such as the existence of prenyl group
at A-ring and 20,40-(OH)2 substitution at B-ring of prenylflavonoids.
( )Leachianone G 1b, the most potent one, would be a promising
structural template for the development of novel and more effi-
cient vasorelaxant and neuroprotective agents.
Further studies of ( )Leachianone G 1b are in progress in order
to clarify the precise mechanism of its vasorelaxant and neuropro-
tective effects.
Acknowledgements
Figure 1. Effects of potent prenylflavonoids (1a, 1b, 1e, 3a and 4b) together with
( )Homoeriodictyol on relaxation in aortic rings with endothelium pre-contracted
with 1 lM phenylephrine (PE) in concentration-dependent manner. Results are
expressed as mean SD (n = 3–4).
The authors are grateful to the support provided by National
Undergraduate Innovative Training program (No. G2008029), and
supports from School of Medicine, Zhejiang University for carrying
out vasorelaxant effect assays.
activities. The results were consistent with previous studies which
indicated prenyl groups contributed greatly to various biological
activities of flavonoids.11–13
Supplementary data
Supplementary data associated with this article can be found, in
Probe on different substituent groups at B-ring of prenylflavo-
noids was followed after the discussion on the effects of molecular
skeleton and prenyl groups. The results indicated that both of the
optimal vasorelaxant and neuroprotective effects were also inten-
sely associated with the presence of hydroxyl groups (Emax and cell
viability: 1a–b, 1e > 1f–g), while three contiguous hydroxyl groups
at B-ring attenuated the activities (Emax and cell viability: 1b,
4b > 1d, 4d). For example, ( )Leachianone G 1b which bear 8-pre-
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Figure 2. Neuroprotective effects of prenylflavonoids 1b, 1e and 4b on OGD-
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cell viability. Date are reported as mean SD (n = 4–6), *P < 0.05 versus OGD alone.