Four New Compounds from the Australian Brown Alga Cystophora brownii

1998 ◽  
Vol 51 (12) ◽  
pp. 1157 ◽  
Author(s):  
Baohong Bian ◽  
Ian A. van Altena
Keyword(s):  
Brown Alga ◽  
Two Dimensional ◽  
Chemical Methods ◽  
New Compounds

Two new steroids, (20S)-3β,20-dihydroxyergosta-5,24(28)-dien-16-one (7) and 3β-hydroxyergosta-5,24(28)-dien-16-one (9), and two new diastereoisomeric meroditerpenes, compounds (10) and (11), † have been isolated from the brown alga Cystophora brownii (Cystoseiraceae). Their structures were elucidated by one- and two-dimensional n.m.r. and other spectrometric and chemical methods.

Regioselective synthesis of new 7,8-dichlorobenzofuro[3,2-c]quinoline-6,9,10(5H)-triones from reactions of 4-hydroxy-2-quinolones with 3,4,5,6-tetrachloro-1,2-benzoquinone

2020 ◽  
Vol 44 (7-8) ◽  
pp. 388-392
Author(s):  
Ashraf A Aly ◽  
Alaa A Hassan ◽  
Nasr K Mohamed ◽  
Lamiaa E Abd El-Haleem ◽  
Stefan Bräse
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Elemental Analysis ◽  
Mass Spectra ◽  
Regioselective Synthesis ◽  
Two Dimensional ◽  
New Compounds ◽  
Nuclear Magnetic

A novel series of 7,8-dichlorobenzofuro[3,2- c]quinoline-6,9,10(5 H)-triones was obtained regioselectively in good yields. The products were formed by the reactions of the 4-hydroxy-2(1 H)-quinolinones with 3,4,5,6-tetrachloro-1,2-benzoquinone in tetrahydrofuran as the solvent. Infrared, nuclear magnetic resonance (two-dimensional nuclear magnetic resonance), mass spectra and elemental analysis were used to elucidate the structures of new compounds.

Physical Properties of New Compounds RMg2Ni9(R=La, Ce, Pr, Nd and Gd) with a Two Dimensional Rare Earth Arrangement

1998 ◽  
Vol 67 (7) ◽  
pp. 2201-2204 ◽  
Author(s):  
Hidetaka Fukuda ◽  
Karim Kadir ◽  
Yasuyoshi Matsumoto ◽  
Takashi Suzuki ◽  
Hironobu Fujii ◽  
...  
Keyword(s):  
Rare Earth ◽  
Physical Properties ◽  
Two Dimensional ◽  
New Compounds

Spectral and bonding properties of bis(N,N-disubstituted-dithiocarbamato)iron(III)dihalide complexes studied by experimental and EHMO quantum-chemical methods

1985 ◽  
Vol 63 (11) ◽  
pp. 3249-3255 ◽  
Author(s):  
George A. Katsoulos ◽  
Constantinos A. Tsipis ◽  
Fotios D. Vakoulis
Keyword(s):  
Magnetic Susceptibility ◽  
Thermogravimetric Analysis ◽  
Quantum Chemical ◽  
Analysis Data ◽  
Spectroscopic Methods ◽  
Chemical Methods ◽  
Magnetic Systems ◽  
Quantum Chemical Methods ◽  
Bonding Properties ◽  
New Compounds

A new series of homobinuclear iron(III) halobisdithiocarbamate complexes antiferromagnetically coupled through a molecular halogen bridging unit has been synthesised and studied. The complexes have been characterized chemically and by spectroscopic methods and magnetic susceptibility measurements. The volatility characteristics and thermogravimetric analysis data for the new compounds are also studied. Finally, quantum-chemical calculations have been used to provide a qualitative guide to the possible pathways for the superexchange processes observed in these molecular magnetic systems, as well as to interpret their electronic spectra.

scholarly journals Novel Ecdysteroids fromSerratula wolffii

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Attila Ványolós ◽  
Zoltán Béni ◽  
Miklós Dékány ◽  
András Simon ◽  
Mária Báthori
Keyword(s):  
Methanolic Extract ◽  
Spectroscopic Techniques ◽  
Two Dimensional ◽  
Nmr Methods ◽  
New Compounds ◽  
Ponasterone A

Two new and one known ecdysteroids were identified in the methanolic extract of the roots ofSerratula wolffii. The new compounds isolated were ponasterone A-22-apioside (1) and 3-epi-shidasterone (3), together with the known 3-epi-22-deoxy-20-hydroxyecdysone (2). The structures of compounds1–3were determined by extensive spectroscopic techniques, including one- and two-dimensional NMR methods.

Terpenoids From the Brown Alga Cystophora moniliformis

1988 ◽  
Vol 41 (1) ◽  
pp. 49 ◽  
Author(s):  
IA Vanaltena
Keyword(s):  
Brown Alga ◽  
Major Metabolite ◽  
New Compounds

The alga Cystophora moniliformis contains two new bisnorsesquiterpenes, (5E,9E)-5,6-epoxy-6,10,14-trimethylpentadeca-9,13-dien-2-one (3) and its cyclized derivative (4), and the (2E) and (2Z) isomers of geranylgeranal epoxide, (5) and (6), respectively. The structures of the new compounds were deduced by spectroscopic means. Geranylacetone (1) was the major metabolite present in the alga.

scholarly journals Dibromopyrrole Alkaloids from the Marine Sponge Acanthostylotella sp

2009 ◽  
Vol 4 (1) ◽  
pp. 1934578X0900400 ◽  
Author(s):  
Sherif Saeed Ebada ◽  
RuAngelie Edrada-Ebel ◽  
Nicole J. de Voogd ◽  
Victor Wray ◽  
Peter Proksch
Keyword(s):  
Natural Products ◽  
Carboxylic Acid ◽  
Methyl Ester ◽  
Marine Sponge ◽  
Two Dimensional ◽  
New Compounds

Fourteen dibromopyrrole alkaloids were isolated from the marine sponge Acanthostylotella sp. collected in Indonesia. In addition to the known compounds 4,5-dibromo-N-(methoxy-methyl)-1 H-pyrrole-2-carboxamide (7), 4,5-dibromo-1 H-pyrrole-2-carboxamide (8), mukanadin D (9), (±)-longamide B methyl ester (10), (±)-longamide B (11), (±)-longamide (12), 3,4-dibromo-1 H-pyrrole-2-carboxamide (13), 2-cyano-4,5-dibromo-1 H-pyrrole (14), six compounds were isolated that proved to be new natural products including acanthamides A – D (1 – 4), methyl 3,4-dibromo-1 H-pyrrole-2-carboxylate (5) and 3,5-dibromo-1 H-pyrrole-2-carboxylic acid (6). The structures of the new compounds were unequivocally identified based on one and two dimensional NMR and on HRFTMS as well as by comparison with the literature.

New Phenolic Glycosides and Lignans from the Roots of Lilium dauricum

Planta Medica ◽  
2021 ◽  
Author(s):  
Xiao Xia ◽  
Jiao Zhang ◽  
Xiao-Jiang Wang ◽  
Yan Lu ◽  
Dao-Feng Chen
Keyword(s):  
Inhibitory Activity ◽  
Phenolic Glycosides ◽  
Anticomplementary Activity ◽  
Chemical Methods ◽  
Electronic Circular Dichroism ◽  
Circular Dichroism Analysis ◽  
Ic50 Values ◽  
The Absolute ◽  
New Compounds ◽  
Circular Dichroïsm

AbstractThree new phenolic glycosides, carvacrol-2-O-β-D-apiofuranosyl-(1 → 6)-β-D-glucopyranoside (1), 1-methyl-3-isopropylphenol-4-O-β-D-apiofuranosyl-(1 → 6)-β-D-glucopyranoside (2), p-methoxythymol-5-O-β-D-apiofuranosyl-(1 → 6)-β-D-glucopyranoside (3), and a pair of new 8-O-4′ neolignan enantiomers (5a/5b), together with 26 known compounds (4, 6 – 30) were isolated from the roots of Lilium dauricum. The structures of the new compounds were elucidated based on extensive spectroscopic and chemical methods, and the absolute configurations of 5a and 5b were established by electronic circular dichroism analysis. Nine compounds (1, 3, 4, 8, 9, 17, 25, 29, and 30) exhibited potent α-glucosidase inhibitory activity with IC50 values ranging from 73.4 µM to 988.2 µM. Besides, compound 19 displayed strong anticomplementary activity (CH50: 71.6 µM).

Diterpenoid Hydroperoxides from the Far-Eastern Brown Alga Dictyota dichotoma

2009 ◽  
Vol 62 (9) ◽  
pp. 1185 ◽  
Author(s):  
Sophia A. Kolesnikova ◽  
Ekaterina G. Lyakhova ◽  
Anatoly I. Kalinovsky ◽  
Pavel S. Dmitrenok ◽  
Sergei A. Dyshlovoy ◽  
...  
Keyword(s):  
Cell Lines ◽  
Brown Alga ◽  
Human Cancer ◽  
Algal Species ◽  
Human Cancer Cell ◽  
Dictyota Dichotoma ◽  
Human Cancer Cell Lines ◽  
New Compounds ◽  
Far Eastern ◽  
First Time

Two new compounds, dictyohydroperoxide 1 and hydroperoxyacetoxycrenulide 2, (Scheme 1) containing hydroperoxyl groups rarely found in algal terpenoids were isolated from the Russian population of brown alga Dictyota dichotoma. The known compounds acetoxycrenulide 4 and squalene were also found in this algal species for the first time. Some of the isolated compounds showed moderate cytoxicity against human cancer cell lines.

scholarly journals New 3-Hydroxyquinaldic Acid Derivatives from Cultures of the Marine Derived Actinomycete Streptomyces cyaneofuscatus M-157

Marine Drugs ◽  
2018 ◽  
Vol 16 (10) ◽  
pp. 371 ◽  
Author(s):  
Francisco Ortiz-López ◽  
Elsa Alcalde ◽  
Aida Sarmiento-Vizcaíno ◽  
Caridad Díaz ◽  
Bastien Cautain ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
2D Nmr ◽  
Two Dimensional ◽  
Amino Acid Residues ◽  
Trace Level ◽  
One Dimensional ◽  
2D Nmr Spectra ◽  
Ic50 Values ◽  
New Compounds ◽  
Tof Ms

Fractionation of the bioactive extract of a culture of the marine derived actinomycete Streptomyces cyaneofuscatus M-157 led to the isolation of the known 3-hydroxyquinaldic acid (4), its amide (5) and three new derivatives (1–3) containing different amino acid residues. The structures of the new molecules (1–3), including their absolute configuration, were determined by the analysis of their ESI-TOF MS and one-dimensional (1D) and two-dimensional (2D) NMR spectra and advanced Marfey’s analysis of their hydrolyzation products. Compound 3 spontaneously dimerized in solution to give the disulfide derivative 6. Unfortunately, none of the new compounds isolated confirmed the antimicrobial activity found in the bacterial extract, perhaps indicating that such antibacterial activity might be due to presence in the extract at the trace level of larger bioactive 3-hydroxyquinaldic acid derivatives from which compounds 1–3 are biosynthetic precursors. Cytotoxicity tests confirmed the moderate and weak IC50 values of 15.6 and 51.5 µM for compounds 5 and 1, respectively.

Monomers, chains, ladders, and two-dimensional sheets: Structural diversity in six new compounds of Zn(II) with 4,4′-bipyridine

Polyhedron ◽  
2006 ◽  
Vol 25 (13) ◽  
pp. 2605-2615 ◽  
Author(s):  
Jonathan D. Woodward ◽  
Rénal V. Backov ◽  
Khalil A. Abboud ◽  
Daniel R. Talham
Keyword(s):  
Structural Diversity ◽  
Two Dimensional ◽  
New Compounds
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