TY - JOUR
T1 - Guaianolide sesquiterpene lactones from Centaurothamnus maximus
AU - Hussien, Taha A.
AU - Mohamed, Tarik A.
AU - Elshamy, Abdelsamed I.
AU - Moustafa, Mahmoud F.
AU - El-Seedi, Hesham R.
AU - Pare, Paul W.
AU - Hegazy, Mohamed Elamir F.
N1 - Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2021/4/1
Y1 - 2021/4/1
N2 - Centaurothamnus maximus (family Asteraceae), is a leafy shrub indigenous to the south-western Arabian Peninsula. With a paucity of phytochemical data on this species, we set out to chemically characterize the plant. From the aerial parts, two newly identified guaianolides were isolated: 3β-hydroxy-4α(acetoxy)-4β(hydroxymethyl)-8α-(4-hydroxy methacrylate)-1αH,5αH, 6αH-gual-10(14),11(13)-dien-6,12-olide (1) and 15-descarboxy picrolide A (2). Seven previously reported compounds were also isolated: 3β, 4α, 8α-trihydroxy-4-(hydroxymethyl)-lαH, 5αH, 6βH, 7αH-guai-10(14),11(13)-dien-6,12-olide (3), chlorohyssopifolin B (4), cynaropikrin (5), hydroxyjanerin (6), chlorojanerin (7), isorhamnetin (8), and quercetagetin-3,6-dimethyl ether-4’-O-β-D-pyranoglucoside (9). Chemical structures were elucidated using spectroscopic techniques, including High Resolution Fast Atom Bombardment Mass Spectrometry (HR-FAB-MS), 1D NMR;1 H,13 C NMR, Distortionless Enhancement by Polarization Transfer (DEPT), and 2D NMR (1 H-1 H COSY, HMQC, HMBC) anal-yses. In addition, a biosynthetic pathway for compounds 1–9 is proposed. The chemotaxonomic significance of the reported sesquiterpenoids and flavonoids considering reports from other Centaurea species is examined.
AB - Centaurothamnus maximus (family Asteraceae), is a leafy shrub indigenous to the south-western Arabian Peninsula. With a paucity of phytochemical data on this species, we set out to chemically characterize the plant. From the aerial parts, two newly identified guaianolides were isolated: 3β-hydroxy-4α(acetoxy)-4β(hydroxymethyl)-8α-(4-hydroxy methacrylate)-1αH,5αH, 6αH-gual-10(14),11(13)-dien-6,12-olide (1) and 15-descarboxy picrolide A (2). Seven previously reported compounds were also isolated: 3β, 4α, 8α-trihydroxy-4-(hydroxymethyl)-lαH, 5αH, 6βH, 7αH-guai-10(14),11(13)-dien-6,12-olide (3), chlorohyssopifolin B (4), cynaropikrin (5), hydroxyjanerin (6), chlorojanerin (7), isorhamnetin (8), and quercetagetin-3,6-dimethyl ether-4’-O-β-D-pyranoglucoside (9). Chemical structures were elucidated using spectroscopic techniques, including High Resolution Fast Atom Bombardment Mass Spectrometry (HR-FAB-MS), 1D NMR;1 H,13 C NMR, Distortionless Enhancement by Polarization Transfer (DEPT), and 2D NMR (1 H-1 H COSY, HMQC, HMBC) anal-yses. In addition, a biosynthetic pathway for compounds 1–9 is proposed. The chemotaxonomic significance of the reported sesquiterpenoids and flavonoids considering reports from other Centaurea species is examined.
KW - Asteraceae
KW - Biosynthesis
KW - Centaurothamnus maximus
KW - Chemotaxonomy
KW - Flavonoids
KW - Guaianolides
UR - http://www.scopus.com/inward/record.url?scp=85105171060&partnerID=8YFLogxK
U2 - 10.3390/molecules26072055
DO - 10.3390/molecules26072055
M3 - Article
C2 - 33916714
AN - SCOPUS:85105171060
SN - 1420-3049
VL - 26
JO - Molecules
JF - Molecules
IS - 7
M1 - 2055
ER -