4th EucheMs chemistry congress

Poster Session 1
s1086
chem. Listy 106, s587–s1425 (2012)
Poster session 1 - organic chemistry
P - 0 4 4 9
SyntheSiS of new fLuoreSCent BuiLdinG
BLoCK BASed on ChoLeSteroL,
PhenyLALAnine And CouMArine
L. SKorPiLovA 1 , M. JurASeK 1 , P. drASAr 1 ,
z. wiMMer 2
1 Institute of Chemical Technology in Prague, Chemistry of
Natural compounds, Prague 6, Czech Republic
2 Institute of Experimental Botany AS CR v.v.i., Isotope
Laboratory, Prague 4, Czech Republic
Cholesterol as a fundamental steroidal unit remains in
interest of both organic chemists and biochemists. It is known,
that cholesterol derivatives represent model and emerging class
of chiral liquid crystals. Moreover, this highly lipophilic
compound may serve as molecule which helps to deliver certain
pharmacophore to targeting tissue. In this labor as a central linker
4-azido or 4-iodo L-phenylalanine were used. The α-amino group
of L-Ala was derived in both cases by fluorescent coumarine
marker, aromatic azide was introduced into Huisgen
1,3-dipolar cycloaddition and iodo derivative into Sonogashira
cross-coupling reaction with propargylated cholesterol. These
compounds themselves may well be interesting from both, the
supramolecular point of view, as well as, subsequent
derivatization which is enabled due to the carboxylic acid
functionality remains the only non-derived unit in the molecule.
Acknowledgment: Grant P503/11/0616 (GACR) and
MSM6046137305 (MSMT).
Keywords: cholesterol; fluoprescence; click chemistry; cross
coupling;
4 th EucheMs chemistry congress
P - 0 4 5 0
effiCient SyntheSiS of new
PoLyhydroxyLAted fLAvon-3-oLS
J. L. C. SouSA 1 , A. M. S. SiLvA 1
1 University of Aveiro, Department of Chemistry & QOPNA,
3810-193 Aveiro, Portugal
The flavonoids are prominent components of citrus fruits,
seeds, olive oil, tea, red wine and other food sources. They are
part of the human diet and can show important beneficial effects
on human health [1] . The flavonols are a subclass of this
family of low molecular weight compounds, which have a
3-hydroxyflavone backbone. These oxygen heterocyclic
compounds have been identified as fulfilling most of the
necessary criteria to present a strong antioxidant activity, because
they present a C2 = C3 double bond conjugated with the 4-keto
group, an ortho-dihydroxy-substitution on ring B and free
OH groups at the C-3 and C-5 positions [2] . Examples of some
well-known naturally occurring flavonols are quercetin,
kaempferol, myricetin, among others.
In the present work, 3-hydroxyflavones were prepared
through a two-step synthetic route, namely an aldol condensation
of appropriate 2'-hydroxyacetophenones and benzaldehydes [3] and
an Algar-Flynn-Oyamada reaction [4] , ending with the cleavage of
the protecting groups. The experimental procedures and results of
this study as well as the structural characterization of the new
compounds will be presented and discussed in this
communication.
Acknowledgements: Thanks are due to the University of Aveiro,
Fundacio para a Ciencia e a Tecnologia (FCT, Portugal) and
FEDER for funding the Organic Chemistry Research Unit
(project PEst-C/QUI/UI0062/2011) and the Portuguese
National NMR Network. J.L.C. Sousa is also grateful to FCT for
her PhD grant (SFRH/BD/76407/2011).
references:
1. Middleton Jr., E.; Kandaswami, C.; Theoharides, T.C.,
Pharmacol. Rev. 2000, 52, 673-751.
2. Gomes, A.; Neuwirth, O.; Freitas, M.; Couto, D.; Ribeiro,
D.; Figueiredo, A.G.P.R.; Silva, A.M.S.; Seixas, R.S.G.R.;
Pinto, D.C.G.A.; Tomé, A.C.; Cavaleiro, J.A.S.;
Fernandes, E.; Lima, J.L.F.C., Bioorg. Med. Chem. 2009,
17, 7218-7226.
3. De la Torre, M.D.L.; Rodrigues, A.G.P.; Tomé, A.C.;
Silva, A.M.S.; Cavaleiro, J.A.S., Tetrahedron 2004, 60,
3581-3592.
4. Dahlén, K.; Wallén, E.A.A.; Gr?tli, M.; Luthman, K.,
J. Org. Chem. 2006, 71, 6863-6871.
Keywords: Antioxidants; Cyclization; NMR spectroscopy;
Oxygen heterocycles; Protecting groups;
AUGUst 26–30, 2012, PrAGUE, cZEcH rEPUbLIc