scholarly journals A simple route to deuterated polystyrene block copolymers by reverse iodine transfer polymerisation

2015 ◽  
Vol 6 (17) ◽  
pp. 3236-3244 ◽  
Author(s):  
Trevor Gavin Wright ◽  
Harald Pasch

For the first time, deuterated polystyrene block copolymers were synthesized by RITP and analysed by advanced fractionation and spectroscopic methods.

2011 ◽  
Vol 6 (11) ◽  
pp. 1934578X1100601 ◽  
Author(s):  
Jaroslaw Moldoch ◽  
Barbara Szajwaj ◽  
Milena Masullo ◽  
Lukasz Pecio ◽  
Wieslaw Oleszek ◽  
...  

A new C-6 flavone glycoside (6), together with seven known compounds, cryptochlorogenic acid (1), chlorogenic acid (2), 2- O- trans-caffeoylhydrocitric acid (3), isovitexin 7-β-D-glucopyranoside (4), 7,4′-dihydroxy-5-methoxyflavone-6- C-β-D-glucopyranoside (5), 3,5- O-dicaffeoylquinic acid (7) and 4,5- O-dicaffeoylquinic acid (8), were isolated from the aerial parts of Knautia arvensis. Their structures were elucidated by extensive spectroscopic methods including 1D- (1H, 13C and TOCSY) and 2D-NMR (DQF-COSY, HSQC, HMBC) experiments, as well as ESIMS analysis. Compounds 1, 3-5 and 8 are reported for the first time in Knautia arvensis.


2001 ◽  
Vol 56 (7-8) ◽  
pp. 521-525 ◽  
Author(s):  
Denata Kasaj ◽  
Liselotte Krenn ◽  
Sonja Prinz ◽  
Antje Hüfner ◽  
Shi Shan Yuc ◽  
...  

The detailed investigation of a methanolic extract of aerial parts of Achillea pannonica SCHEELE. within a chemotaxonomic study led to the isolation of 6 flavonoid glycosides. Besides rutin, apigenin-7-O-glucopyranoside, luteolin-7-O-glucopyranoside, apigenin-7-O-rutinoside and acacetin-7-O-rutinoside, an unusual flavondiglucoside was isolated. Its structure was established by UV, 1HNMR and 13C NMR spectroscopic methods including 2D-NMR techniques and ESI-MS as luteolin-7,4′-O-β-diglucoside. This substance is reported for the first time in the genus Achillea. Chemotaxonomic aspects are discussed briefly


2011 ◽  
Vol 76 (9) ◽  
pp. 1133-1139 ◽  
Author(s):  
Pham Thi Nhat Trinh ◽  
Nguyen Cong Hao ◽  
Phan Thanh Thao ◽  
Le Tien Dung

From the ethanol extract of Drynaria fortunei (KUNZE) J. Sm., a new phenylpropanoid glycoside, fortunamide (1), was isolated and characterized by spectroscopic methods. Together with a new glycoside, 9 known compounds, including three curcuminoids (2–4), two isoprenylated flavonoids (5, 6), two flavonoids (7, 8), one monoterpenoid (9) and one phenolic acid (10) were isolated and identified by spectral data analysis from the rhizomes of Drynaria fortunei (KUNZE) J. Sm. Eight of them were isolated from Drynaria fortunei (KUNZE) J. Sm. for the first time.


2022 ◽  
Vol 12 ◽  
Author(s):  
Robin Huber ◽  
Laurence Marcourt ◽  
Alexey Koval ◽  
Sylvain Schnee ◽  
Davide Righi ◽  
...  

In this study, a series of complex phenylpropanoid derivatives were obtained by chemoenzymatic biotransformation of ferulic acid, caffeic acid, and a mixture of both acids using the enzymatic secretome of Botrytis cinerea. These substrates were incubated with fungal enzymes, and the reactions were monitored using state-of-the-art analytical methods. Under such conditions, a series of dimers, trimers, and tetramers were generated. The reactions were optimized and scaled up. The resulting mixtures were purified by high-resolution semi-preparative HPLC combined with dry load introduction. This approach generated a series of 23 phenylpropanoid derivatives, 11 of which are described here for the first time. These compounds are divided into 12 dimers, 9 trimers (including a completely new structural scaffold), and 2 tetramers. Elucidation of their structures was performed with classical spectroscopic methods such as NMR and HRESIMS analyses. The resulting compound series were analyzed for anti-Wnt activity in TNBC cells, with several derivatives demonstrating specific inhibition.


2019 ◽  
Vol 57 (2) ◽  
pp. 162
Author(s):  
Quan Minh Pham ◽  
Hoai Van Thi Tran ◽  
Lam Tien Do ◽  
Phuong Lan Doan ◽  
Inh Thi Cam ◽  
...  

Urena lobata L. is used in Vietnamese traditional medicine for the treatment of several diseases. Tree roots are used to treat rheumatism, dysentery, poor digestion, flu, tonsils, malaria, asthma, goiter. Flowers are used to treat chickenpox, fever, and mental disorders. Branches, leaves or whole trees used to treat injuries bruises, rheumatism, mastitis, bites. Phytochemical investigation of the n-hexan and ethyl acetate extract of Urena lobata L. led to the isolation of β-sitosterol (1), β-sitosterol-3-O-β-D-glucopyranoside (2), a-acetylamino-phenylpropyl a-benzoylamino-phenylpropanoate (3), quercetin (4), and trans-tiliroside (5). Their chemical structures were determined by spectroscopic methods including MS, 1D, 2D NMR and comparing with those reported in previous papers. Two compounds 3, 5 were isolated for the first time from Urena lobata plant.


Planta Medica ◽  
2018 ◽  
Vol 85 (03) ◽  
pp. 225-230 ◽  
Author(s):  
Xinhui Wang ◽  
Dujuan Wang ◽  
Xue Wang ◽  
Manana Khutsishvili ◽  
Kamilla Tamanyan ◽  
...  

AbstractPhytochemical investigation of Camphorosma lessingii has resulted in the isolation of four previously unreported isoflavones (1–4) and eight known compounds (5–12). Nine of these compounds (1–6, 8–10) are reported for the first time from members of the family Amaranthaceae. The structures of all isolated compounds were determined by spectroscopic methods, primarily one-dimensional and two-dimensional nuclear magnetic resonance and mass spectrometry. The absolute configuration of 6 was confirmed by circular dichroism. Inhibition of the organic anion transporters, OAT1 and OAT3, by the isolated compounds was evaluated. Among them, 7, 2′-dihydroxy- 6,8-dimethoxyisoflavone (1), 2′-hydroxy-6,7,8-trimethoxyisoflavone (2), 6,2′-dihydroxy-7,8-dimethoxyisoflavone (3), and 7-methoxyflavone (5) showed a significant inhibitory effect on 6-carboxyfluorescein uptake mediated by OAT1 and OAT3.


2013 ◽  
Vol 8 (8) ◽  
pp. 1934578X1300800 ◽  
Author(s):  
Hsu-Ming Chung ◽  
Wei-Hsien Wang ◽  
Tsong-Long Hwang ◽  
Yang-Chang Wu ◽  
Ping-Jyun Sung

Three natural clovane-related sesquiterpenoids, 2β-acetoxyclovan-9α-ol (1), 9α-acetoxyclovan-2β-ol (2) and clovan-2β,9β-diol (3), were isolated from the gorgonian coral Rumphella antipathies. The structures of clovanes 1–3 were elucidated by spectroscopic methods and by comparison of the spectral data with those of known clovane analogues. This is the first time that clovanes 1–3 have been isolated from a natural source. Clovanes 1 and 2 displayed inhibitory effects on the generation of superoxide anions and the release of elastase by human neutrophils.


2016 ◽  
Vol 11 (5) ◽  
pp. 1934578X1601100
Author(s):  
Wei Luo ◽  
Yaya Wen ◽  
Yanbei Tu ◽  
Hongjian Du ◽  
Qin Li ◽  
...  

Ten flavonoids (1–10), including a new glycoside (nevadensin-7-sambubioside, 7), together with a phenylpropanoid glycoside (11) were isolated from Lysionotus pauciflorus. Their structures were elucidated by a combination of spectroscopic methods and comparing with literature data. Five compounds (1, 3, 4, 8, and 9) were obtained from the family Gesneriaceae for the first time. The new compound was evaluated in vitro for anticholinesterase activities against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), but was found to be inactive.


Molecules ◽  
2019 ◽  
Vol 24 (3) ◽  
pp. 620 ◽  
Author(s):  
Xiaowei Sun ◽  
Huijiao Yan ◽  
Yujie Zhang ◽  
Xiao Wang ◽  
Dawei Qin ◽  
...  

Seven diterpene lactones, andrographolide (1), isoandrographolide (2), neo-andrographolide (3), 14-deoxy-11,12-didehydroandrographolide (4), 14-deoxyandrographiside (5), 14-deoxy-11,12-didehydroandrographiside (6), 3,14-dideoxyandrographolide (10), and three flavones, andrographidine C (7), andrographidine A (8), 5-hydroxy-7,8-dimethoxyflavanone (9) have been successfully and efficiently isolated from A. paniculata using an off-line two dimensional (2D) high-speed counter-current chromatography (HSCCC) method for the first time. For the first dimension HSCCC separation, petroleum ether-ethyl acetate-methanol-water 3:7:5:5 (v/v) was employed to isolate 14.4 mg of compound 1, 3.1 mg of compound 2, 7.8 mg of compound 3, and 18.0 mg of compound 4 from 200 mg of the A. paniculata extract. For the second dimension HSCCC separation, petroleum ether-ethyl acetate-methanol-water 2:8:1:9 (v/v) and 5:5:6:4 (v/v) were employed to isolate the collected fractions ranged from 55 to 79 min and the flow out fraction, respectively, which led to 5.1 mg of compound 5, 4.4 mg of compound 6, 2.4 mg of compound 7, 3.3 mg of compound 8, 4.0 mg of compound 9, 7.0 mg of compound 10. The structures of these diterpene lactones and flavones were elucidated by extensive spectroscopic methods.


2010 ◽  
Vol 5 (2) ◽  
pp. 1934578X1000500
Author(s):  
Yanhong Gao ◽  
Yanfang Su ◽  
Shilun Yan ◽  
Zhenhai Wu ◽  
Xiao Zhang ◽  
...  

Two flavonoids with an unusual 2′,4′,5′-trisubstituted B-ring (1 and 2), four myricetin derivatives (3-methylmyricetin-3′-O-β-D-xylopyranoside (3), myricetin-3-O-α-L-rhamnopyranoside, myricetin-3-O-β-D-galactopyranoside, and 3-methylmyricetin), and myricetin were isolated from the roots of Pteroxygonum giraldii Damm. & Diels. Their structures were elucidated using various spectroscopic methods and acid hydrolysis. Compound 1 was a new flavonoid and the NMR spectroscopic data of compounds 2 and 3 are reported for the first time.


Sign in / Sign up

Export Citation Format

Share Document