b
), chair-bath type
15
D
5
,
1
D
14
(
с
) and
bath-chair type
15
D
5
,
1
D
14
(
d
) [4]. In
trans-jointed nonlinear melampolides
in a ten-membered ring, only type (
c
)
and
type
(
d
)
were
found
experimentally. In structure
1
, cycle A
adopts the chair-bath conformation of
the
15
D
5
,
1
D
14
type (
c
).
The
lactone
ring
takes
the
conformation of a somewhat distorted
7α-envelope (
С
S
7
=3.9
).
The cycles in 1 are articulated in the trans-type (torsion angle H6C6C7H7 = 159
o
).
References
1. P. Singh, A. Sharma, K. Joshi, J. Jakupovic,F. Bohlmann.
Phytochemistry
,
1985
,
24
, 2023-2028.
2.A. Rustaiyan, K. Zare, M. Ganj, H. Sadri.
Phytochemistry
,
1989
,
28
, 1535-1536.
3. A.F. Beechman.
Tetrahedron
,
1972
,
28
, 5543-5554.
4. Z. Samek, J. Harmatha.
Coll. Czech. Chem. Commun,
,
1978
,
43
, 2779- 2799.
Poster presentation
48
NOVEL FLAVONOID FROM SERRATULA CUPULIFORMIS
L.N.Zibareva, О.А.Kotelnikov, V.S.Sidelnikov, D.I. Kazantseva, S.I. Konnova
National Research Tomsk State University, Russia, 634050, Tomsk region, Tomsk,
Lenin Ave., 36.
Previously, the species
Serratula cupuliformis
Nakai & Kitag. was recommended as
a new plant source of ecdysteroids - 20-hydroxyecdysone, ecdysone, 2-deoxy-20-
hydroxyecdysone and polypodin B (Zibareva et al., 2017).
The plant material was grown from seeds obtained from the Botanical garden of Jena
(Germany) and successfully introduced in the Siberian Botanical Garden of Tomsk
State University. Now this species is presented as a rich source of flavonoids.
In the process of isolation by selective extraction of secondary metabolites from the
ethanol extract of the aboveground part of
S.cupuliformis
, chloroform, ethyl acetate,
butanol fractions were obtained, the yield of which was, respectively, 0.16; 1.61; 1.97%
of the mass of raw materials. The composition of flavonoids of the ethyl acetate fraction
was studied, some of which were identified based on HPLC data and comparison with
the characteristics of standards. The presence of at least 20 flavonoids with different
absorption maxima – 270/335, 267/344, 251/351, 252/366 nm - was found in the
aboveground part. The structure of the individual flavonoid isolated by column
chromatography was established by HPLC-MS and
1
H and
13
C NMR methods. The
value of m/z 315.0 corresponds to the molecular ion [M-H]-, m/z 300.0 corresponds to a
fragmentary ion formed by the cleavage of a methyl group from a molecular ion. The
mass spectrum of the sample according to the molecular ion and the nature of
fragmentation corresponds to a substance with the gross formula С
16
H
12
O
7
.
Fig.
13
C-NMR spectrum of the studied flavonoid
According to the results of the studies conducted by liquid chromatography-mass
spectrometry and NMR spectroscopy, by the mass of the molecular ion, the nature of
fragmentation, the number of signals and areas of chemical shifts it was found that the
compound under study corresponds to the substance 2-(2,4-dihydroxyphenyl)-5,7-
dihydroxy-3-methoxy-4H-chromene-4-one. This flavonoid was isolated for the first
time.
Poster presentation
49
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