ISOLATION AND CRYSTAL STRUCTURE OF 8α,14- DIHYDROXY-11,13-DIHYDROMELAMPOLIDE K.M. Turdybekov 1 , A.S. Serik 1 , R.I. Jalmakhanbetova 2 , Y.M. Suleimen 3 , Kristofer Van Hecke 4 1 E.A. Buketov Karaganda University, st. University, 28, Karaganda, Republic of Kazakhstan 2 L.N. Gumilyov Eurasian National University, st. Satbaeva, 2, Nur-Sultan, Republic of Kazakhstan 3 Sh. Ualikhanov Kokshetau University, st. Temirbekova, 30, Kokshetau, Republic of Kazakhstan 4 XStruct, Department of Chemistry, Ghent University, Ghent B-9000, Belgium 8α,14-Dihydroxygermacra-1(10)E,4E-dien-6β,7α,11βH-12,6-olide
(8α,14-
Dihydroxy-11,13-dihydromelampolide)] (
1) , C
15
H
23
O
4
, was isolated from the
Artemisia sublessingiana [1,2]. Compounds
1 was isolated from
Artemisia species for the first
time.
To establish the spatial structure, an X-ray diffraction study 1 was carried out, the
general view of which is shown in the figure. The configuration of the C6, C7, C8, and
C11 chiral centers is correlated with that known in germacranolides [3]. The Fleck
parameter was -0.04(7).
According to the conformational analysis carried out in 1(10)Z,4E-germacranolides
(melampolides), the ten-membered
ring
A
can
take
four
main
conformations:
chair-chair
type
15
D
5
,
1
D
14
(
а ), bath-bath type
15
D
5
,
1
D
14
(
