scholarly journals Efficient Total Synthesis of Lissodendrin B, 2-Aminoimidazole Marine Alkaloids Isolated from Lissodendoryx (Acanthodoryx) fibrosa

Marine Drugs ◽  
2019 ◽  
Vol 18 (1) ◽  
pp. 36
Author(s):  
Xianfeng Wei ◽  
Xuelong Hu ◽  
Rilei Yu ◽  
Shengbiao Wan ◽  
Tao Jiang
Keyword(s):  
Total Synthesis ◽  
Triple Bond ◽  
Coupling Reactions ◽  
Sonogashira Coupling ◽  
Marine Alkaloids ◽  
Reaction Conditions ◽  
The Core ◽  
Analog Synthesis ◽  
Biological Studies ◽  
Synthesis Approach

Lissodendrin B is a 2-aminoimidazole alkaloid bearing a (p-hydroxyphenyl) glyoxal moiety that was isolated from the Indonesian sponge Lissodendoryx (Acanthodoryx) fibrosa. We reported the first efficient total synthesis of Lissodendrin B. The precursor 4,5-disubstituted imidazole was obtained through Suzuki coupling and Sonogashira coupling reactions from 4-iodoimidazole. C2-azidation and reduction of the azide then provided the core structures of Lissodendrin B. Subsequent triple-bond oxidation, demethylation, and deacetylation gave the final product. The synthesis approach consists of ten steps with an overall yield of 1.1% under mild reaction conditions, and it can be applied for future analog synthesis and biological studies.

scholarly journals Synthesis of 9-arylalkynyl- and 9-aryl-substituted benzo[b]quinolizinium derivatives by Palladium-mediated cross-coupling reactions

2018 ◽  
Vol 14 ◽  
pp. 1871-1884 ◽  
Author(s):  
Siva Sankar Murthy Bandaru ◽  
Darinka Dzubiel ◽  
Heiko Ihmels ◽  
Mohebodin Karbasiyoun ◽  
Mohamed M A Mahmoud ◽  
...  
Keyword(s):  
Emission Intensity ◽  
Binding Constants ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
Sonogashira Coupling ◽  
Reaction Conditions ◽  
Quadruplex Dna ◽  
Cross Coupling Reactions ◽  
Sonogashira Coupling Reaction

9-Arylbenzo[b]quinolizinium derivatives were prepared with base-free Suzuki–Miyaura coupling reactions between benzo[b]quinolizinium-9-trifluoroborate and selected benzenediazonium salts. In addition, the Sonogashira coupling reaction between 9-iodobenzo[b]quinolizinium and the arylalkyne derivatives yielded four novel 9-(arylethynyl)benzo[b]quinolizinium derivatives under relatively mild reaction conditions. The 9-(N,N-dimethylaminophenylethynyl)benzo[b]quinolizinium is only very weakly emitting, but the emission intensity increases by a factor >200 upon protonation, so that this derivative may operate as pH-sensitive light-up probe. Photometric and fluorimetric titrations of duplex and quadruplex DNA to 9-(arylethynyl)benzo[b]quinolizinium derivatives revealed a significant binding affinity of these compounds towards both DNA forms with binding constants ofKb= 0.2–2.2 × 105M−1.

PEPPSI-SONO-SP2: a new highly efficient ligand-free catalyst system for the synthesis of tri-substituted triazine derivatives via Suzuki–Miyaura and Sonogashira coupling reactions under a green approach

2016 ◽  
Vol 40 (6) ◽  
pp. 5135-5142 ◽  
Author(s):  
Motakatla Venkata Krishna Reddy ◽  
Peddiahgari Vasu Govardhana Reddy ◽  
Cirandur Suresh Reddy
Keyword(s):  
Palladium Catalyst ◽  
Cross Coupling ◽  
Catalyst System ◽  
Coupling Reactions ◽  
Sonogashira Coupling ◽  
Reaction Conditions ◽  
Cross Coupling Reactions ◽  
Green Approach ◽  
Ligand Free ◽  
Triazine Derivatives

Consecutive Suzuki–Miyaura and Sonogashira cross coupling reactions catalyzed by a new competent palladium catalyst PEPPSI-SONO-SP2 under mild and green reaction conditions.

An Unprecedented Cyano-Induced Sodium Nitrite-Catalyzed C(sp3)-H and C(sp2)-H Coupling Reaction

2018 ◽  
Vol 15 (7) ◽  
pp. 989-994 ◽  
Author(s):  
Ling Li ◽  
Bo Su ◽  
Yuxiu Liu ◽  
Qingmin Wang
Keyword(s):  
Sodium Nitrite ◽  
Oxidative Coupling ◽  
High Resolution Mass Spectrometry ◽  
Coupling Reaction ◽  
13C Nmr Spectroscopy ◽  
Coupling Reactions ◽  
Reaction Conditions ◽  
1H And 13C Nmr ◽  
Oxidative Coupling Reaction ◽  
Oxidative Coupling Reactions

Aim and Objective: During the investigation of sodium nitrite-catalyzed oxidative coupling reaction of aryls, an unprecedented C(sp2)-H and C(sp3)-H coupling of substituted 2-aryl acetonitrile was found. Materials and Methods: The structure of the coupled product was confirmed by 1H and 13C NMR spectroscopy and high-resolution mass spectrometry (HRMS), and comparison of its derivatives with known compounds. The effects of methoxy group in the benzene ring on the reaction were evaluated. Results: The optimized reaction conditions are summarized as follows: CF3SO3H/substrate = 1.5 equiv., NaNO2/substrate = 0.3 equiv., CH3CN as solvent. 2-(4-Methoxyphenyl)acetonitrile and 2-(3,4,5- trimethoxyphenyl)acetonitrile could also generate C(sp2)-H and C(sp3)-H coupling. The coupling reaction occurred as a typical radial mechanism. Conclusion: An unprecedented cyano-induced, NaNO2-catalyzed oxidative C(sp3)-H and C(sp2)-H coupling was reported. The reaction proceeded under very mild conditions, using O2 in the air as terminal oxidant. The unique oxidative manner might provide more inspiration for the development of intriguing oxidative coupling reactions.

Solvent-free and efficient synthesis of bicyclic 2-pyridone derivatives for endoplasmic reticulum imaging

2021 ◽  
Author(s):  
Xiaoyun Ran ◽  
Qian Zhou ◽  
Jin Zhang ◽  
Shanqiang Wang ◽  
Gui Wang ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Citric Acid ◽  
Core Structure ◽  
Solvent Free ◽  
Efficient Synthesis ◽  
The Core ◽  
Catalyst Free ◽  
Synthesis Approach ◽  
Ethylenediamine Derivatives

Started from citric acid (CA) and ethylenediamine derivatives, a solvent-free, catalyst-free and highly yield synthesis approach for bicyclic 2-pyridones was presented. Continuing to modify the core structure, a series of...

Sign in / Sign up

Export Citation Format

Share Document