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A new guaianolide artselenin (1) and a new dimeric guaianolide artselenoid (2), along with 10 known compounds, were isolated from the aerial parts of Artemisia selengensis. Their structures were elucidated by spectroscopic methods. Two-dimensional NMR techniques were used to make complete
Two new guaianolides artemanomalides A and B were isolated from the aerial parts of Artemisia anomala S. Moore. Their structures were characterized as 2-oxo-5α, 10α-dihydroxy-guaia-3-en-1α, 6β, 7α, 11β H-12, 6-olide (1) and 8α-acetoxy-2-oxo-5α, 10α-dihydroxy-guaia-3, 11(13)-dien-1α, 6β, 7αH-12,
Commercially available santonin was used to synthesize seven sesquiterpene lactones using a facile strategy that involved a high-yielding photochemical reaction. Three natural products from Artemisia gorgonum were synthesized in good yields, and in the case of two compounds, absolute configurations
Investigation of a Chinese folk medicine, Artemisia dubia (syn. Artemisia subdigitata), has resulted in the isolation of eight new guaianolides (artemdubolides A-H, 1-8), and nineteen known sesquiterpene lactones. Their structures were elucidated primarily on the basis of spectroscopic methods,
Five dimeric guaianolides, absinthins A-E, and seven known dimeric guaianolides were isolated from Artemisia absinthium. Their structures were elucidated based on 1D- and 2D-NMR experiments, including (1)H NMR, (13)C NMR, DEPT, (1)H-(1)H COSY, HSQC, HMBC, and NOESY, and through HRESIMS data
The aerial parts of Artemisia myriantha have afforded one new fulvenoguaianolide and four dimeric guaianolides in addition to seven known guaianolides. The structures of all the compounds were elucidated by 2D NMR. It is speculated that the dimeric guianolides are formed via Diels-Alder type
A new dimeric guaianolide (8) and a new glaucolide (3), a seco-guaiaretic acid (4), two guaianolides (6 and 7), and five known sesquiterpene lactones (1, 2, 5, 9, and 10) were isolated from the aerial part of Artemisia anomala. Their structures were determined on the basis of chemical and
11,13-Dehydro seco-guaianolides, a particular type of sesquiterpene lactones, were synthesized from the commercially available α-santonin (11) using a facile strategy involving a high-yielding photochemical reaction. Natural products 10 and 17 from Artemisia
This study was performed to investigate the guaianolides from the aerial parts of Artemisia myriantha. The chemical constituents were isolated by chromatographic columns over silica gel, Sephadex LH-20, and ODS, as well as Semi-prep HPLC methods, and their structures were identified by NMR and MS
An unusual dimeric guaianolide, artemilinin A (1) and a sesquiterpene-monoterpene lactone, isoartemisolide (2), were isolated from the leaves of Artemisia argyi. Their structures were elucidated on the basis of extensive spectroscopic analysis (IR, HR-ESIMS, 1D- and 2D-NMR), and the absolute
Artemisians A-D (1-4), the first examples of [4 + 2] Diels-Alder type adducts presumably biosynthesized from a rare 1, 10-4, 5-diseco-guaianolide and a guaianolide diene, along with their possible precursor 5, were isolated from the traditional Chinese medicine Artemisia argyi. The structures of 1-4
Artemisianins A-D (1-4), four stereoisomers of sesquiterpenoid dimers, forming via [4+2] cycloaddition from a 1, 10-seco-guaianolide dienophile and a guaianolide diene, along with two biosynthetically related precurors 5 and 6, were isolated from the famous traditional Chinese medicine Artemisia
Investigation into the chemical diversity of Artemisia argyi led to the discovery of four new (1-4) and one known (5) guaianolide sesquitenpenoid dimers linked via ester bond, and five other known mono-sesquiterpenoids (6-10). Their structures were determined via extensive spectroscopic data, and
A new member of 5αH,6βH,7αH,11αH-guaian-12,6α-olides, 11-epi-8α-hydroxyarborescin, together with a mixture of (24R)- and (24S)-cycloart-25-en-3b,24-diols, palmitic acid and 1-octacosanol were isolated from the leaves of Artemisia roxburghiana Bess. (Asteraceae) of Vietnam. Their structures were
A phytochemical reinvestigation of the aerial parts of Artemisia sieversiana gave a new guaianolide and two known flavones (chrysosplenetin and 5-hydroxy-3',4',6,7-tetramethoxyflavone). Antifungal fractions derived from the chloroform extract of A. annua afforded two cadinane derivatives (arteannuin