Beilstein Journal of Organic Chemistry This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.

Friedel – Crafts acylation of benzene derivatives in tunable aryl alkyl ionic liquids (TAAILs)
Abstract An iron(III) chloride hexahydrate-catalyzed Friedel–Crafts acylation of benzene derivatives in tunable aryl alkyl ionic liquids (TAAILs) has been developed. Through optimization of the metal salt, reaction conditions and ionic liquids, we were able to design a robust catalyst system that tolerates different electron-rich substrates under ambient atmosphere and allows for a multigram scale. Beilstein J. Org. Chem. 2023, 19, 212–216. doi:10.3762/bjoc.19.20 (Source: Beilstein Journal of Organic Chemistry)
Source: Beilstein Journal of Organic Chemistry - February 23, 2023 Category: Chemistry Authors: Beilstein Journal of Organic Chemistry - Syndicated Feeds Tags: Friedel – Crafts acylation homogeneous catalysis ionic liquids iron catalysis TAAILs Full Research Paper Source Type: research

An accelerated Rauhut – Currier dimerization enabled the synthesis of ( ± )-incarvilleatone and anticancer studies
Abstract The total synthesis of racemic incarvilleatone has been achieved by utilizing unexplored accelerated Rauhut–Currier (RC) dimerization. The other key steps of the synthesis are oxa-Michael and aldol reactions in a tandem sequence. Racemic incarvilleatone was separated by chiral HPLC and the configuration of each enantiomer was determined by single-crystal X-ray analysis. In addition, a one-pot synthesis of (±)-incarviditone has been achieved from rac-rengyolone by using KHMDS as a base. We have also assessed the anticancer activity of all the synthesized compounds in breast cancer cells nonetheless, they...
Source: Beilstein Journal of Organic Chemistry - February 21, 2023 Category: Chemistry Authors: Beilstein Journal of Organic Chemistry - Syndicated Feeds Tags: dimerization incarviditone incarvilleatone oxa-Michael Rauhut – Currier Full Research Paper Source Type: research

Germacrene B – a central intermediate in sesquiterpene biosynthesis
Abstract Germacranes are important intermediates in the biosynthesis of eudesmane and guaiane sesquiterpenes. After their initial formation from farnesyl diphosphate, these neutral intermediates can become reprotonated for a second cyclisation to reach the bicyclic eudesmane and guaiane skeletons. This review summarises the accumulated knowledge on eudesmane and guaiane sesquiterpene hydrocarbons and alcohols that potentially arise from the achiral sesquiterpene hydrocarbon germacrene B. Not only compounds isolated from natural sources, but also synthetic compounds are dicussed, with the aim to give a rationale for the str...
Source: Beilstein Journal of Organic Chemistry - February 20, 2023 Category: Chemistry Authors: Beilstein Journal of Organic Chemistry - Syndicated Feeds Tags: biosynthesis configuration determination germacrene B structure elucidation terpenes Review Source Type: research

Sequential hydrozirconation/Pd-catalyzed cross coupling of acyl chlorides towards conjugated (2E,4E)-dienones
Abstract Dienones are challenging building blocks in natural product synthesis due to their high reactivity and complex synthesis. Based on previous work and own initial results, a new stereospecific sequential hydrozirconation/Pd-catalyzed acylation of enynes with acyl chlorides towards conjugated (2E,4E)-dienones is reported. We investigated a number of substrates with different alkyl and aryl substituents in the one-pot reaction and showed that regardless of the substitution pattern, the reactions lead to the stereoselective formation (≥95% (2E,4E)) of the respective dienones under mild conditions. It was found th...
Source: Beilstein Journal of Organic Chemistry - February 17, 2023 Category: Chemistry Authors: Beilstein Journal of Organic Chemistry - Syndicated Feeds Tags: cross coupling hydrozirconation palladium catalysis Schwartz ' s reagent terpenes Full Research Paper Source Type: research

Identification and determination of the absolute configuration of amorph-4-en-10 β -ol, a cadinol-type sesquiterpene from the scent glands of the African reed frog Hyperolius cinnamomeoventris
Abstract Hyperolid reed frogs are one of the few families of Anurans known to possess glands that emit volatile compounds used in chemical communication. Hyperolius cinnamomeoventris, a model species, possesses a gular gland on its vocal sac that emits chemicals, and sends visual and auditory signals during calling. Previous investigations have shown that the glandular compounds are typically macrocyclic lactones. However, in this work, we show that another major constituent of the male specific gland is (10R,1S,6R,7R,10R)-amorph-4-ene-10β-ol [(1R,4R,4aR,8aS)-4-isopropyl-1,6-dimethyl-1,2,3,4,4a,7,8,8a-octahydronaphtha...
Source: Beilstein Journal of Organic Chemistry - February 16, 2023 Category: Chemistry Authors: Beilstein Journal of Organic Chemistry - Syndicated Feeds Tags: Anura chiral gas chromatography enantioselective synthesis GC/MS semiochemicals Full Research Paper Source Type: research

Total synthesis of insect sex pheromones: recent improvements based on iron-mediated cross-coupling chemistry
In this report, we discuss the recent contributions brought by our groups in the field of iron-catalyzed cross-couplings applied to the synthesis of insect pheromones. The pivotal question of the development of sustainable synthetic procedures involving cheap, non-toxic and efficient additives is also discussed, as well as the mechanistic features guiding the reactivity of such catalytic systems. Beilstein J. Org. Chem. 2023, 19, 158–166. doi:10.3762/bjoc.19.15 (Source: Beilstein Journal of Organic Chemistry)
Source: Beilstein Journal of Organic Chemistry - February 14, 2023 Category: Chemistry Authors: Beilstein Journal of Organic Chemistry - Syndicated Feeds Tags: catalysis cross-coupling insect pheromones iron Perspective Source Type: research

Insight into oral amphiphilic cyclodextrin nanoparticles for colorectal cancer: comprehensive mathematical model of drug release kinetic studies and antitumoral efficacy in 3D spheroid colon tumors
This study was carried out to further elucidate oral camptothecin (CPT)-loaded amphiphilic cyclodextrin nanoparticles for the local treatment of colorectal tumors in terms of their drug release behavior and efficacy in 3-dimensional tumor models to predict the in vivo efficacy of different nanocarriers. The main objective was to build a bridge between formulation development and in vitro phase and animal studies. In this context, CPT-loaded polycationic-β-cyclodextrin nanoparticles caused reduced cell viability in CT26 and HT29 colon carcinoma spheroid tumors of mice and human origin, respectively. In addition, the re...
Source: Beilstein Journal of Organic Chemistry - February 13, 2023 Category: Chemistry Authors: Beilstein Journal of Organic Chemistry - Syndicated Feeds Tags: colorectal cancer camptothecin 3D spheroid cyclodextrin oral nanoparticle release kinetics Full Research Paper Source Type: research

Nostochopcerol, a new antibacterial monoacylglycerol from the edible cyanobacterium Nostochopsis lobatus
Abstract A new antibacterial 3-monoacyl-sn-glycerol, nostochopcerol (1), was isolated from a cultured algal mass of the edible cyanobacterium Nostochopsis lobatus MAC0804NAN. The structure of compound 1 was established by the analysis of NMR and MS data while its chirality was established by comparison of optical rotation values with synthetically prepared authentics. Compound 1 inhibited the growth of Bacillus subtilis and Staphylococcus aureus at MIC of 50 μg/mL and 100 μg/mL, respectively. Beilstein J. Org. Chem. 2023, 19, 133–138. doi:10.3762/bjoc.19.13 (Source: Beilstein Journal of Organic Chemistry)
Source: Beilstein Journal of Organic Chemistry - February 9, 2023 Category: Chemistry Authors: Beilstein Journal of Organic Chemistry - Syndicated Feeds Tags: antibacterial cyanobacterium edible monoacylglycerol Nostochopsis lobatus Letter Source Type: research

1,4-Dithianes: attractive C2-building blocks for the synthesis of complex molecular architectures
Abstract This review covers the synthetic applications of 1,4-dithianes, as well as derivatives thereof at various oxidation states. The selected examples show how the specific heterocyclic reactivity can be harnessed for the controlled synthesis of carbon–carbon bonds. The reactivity is compared to and put into context with more common synthetic building blocks, such as 1,3-dithianes and (hetero)aromatic building blocks. 1,4-Dithianes have as yet not been investigated to the same extent as their well-known 1,3-dithiane counterparts, but they do offer attractive transformations that can find good use in the assembly ...
Source: Beilstein Journal of Organic Chemistry - February 2, 2023 Category: Chemistry Authors: Beilstein Journal of Organic Chemistry - Syndicated Feeds Tags: 1,4-dithianes 1,4-dithiins 2,3-dihydro-1,4-dithiins heterocycles target synthesis Review Source Type: research

Synthesis and characterisation of new antimalarial fluorinated triazolopyrazine compounds
Abstract Nine new fluorinated analogues were synthesised by late-stage functionalisation using Diversinate™ chemistry on the Open Source Malaria (OSM) triazolopyrazine scaffold (Series 4). The structures of all analogues were fully characterised by NMR, UV and MS data analysis; three triazolopyrazines were confirmed by X-ray crystal structure analysis. The inhibitory activity of all compounds against the growth of the malaria parasite Plasmodium falciparum (3D7 and Dd2 strains) and the cytotoxicity against a human embryonic kidney (HEK293) cell line were tested. Some of the compounds demonstrated moderate antimalaria...
Source: Beilstein Journal of Organic Chemistry - January 31, 2023 Category: Chemistry Authors: Beilstein Journal of Organic Chemistry - Syndicated Feeds Tags: antimalarial characterisation DiversinateTM fluorine triazolopyrazine scaffold Open Source Malaria Full Research Paper Source Type: research

Practical synthesis of isocoumarins via Rh(III)-catalyzed C – H activation/annulation cascade
Abstract Herein, we report an unprecedented Rh(III)-catalyzed C–H activation/annulation cascade of readily available enaminones with iodonium ylides towards the convenient synthesis of isocoumarins. This coupling system proceeds in useful chemical yields (up to 93%) via a cascade C–H activation, Rh-carbenoid migratory insertion and acid-promoted intramolecular annulation. The success of gram-scale reaction and diverse functionalization of isocoumarins demonstrated the synthetic utility of this protocol. Beilstein J. Org. Chem. 2023, 19, 100–106. doi:10.3762/bjoc.19.10 (Source: Beilstein Journal of Organic Chemistry)
Source: Beilstein Journal of Organic Chemistry - January 30, 2023 Category: Chemistry Authors: Beilstein Journal of Organic Chemistry - Syndicated Feeds Tags: C – H activation enaminone iodonium ylide isocoumarin rhodium catalysis Letter Source Type: research

Revisiting the bromination of 3 β -hydroxycholest-5-ene with CBr4/PPh3 and the subsequent azidolysis of the resulting bromide, disparity in stereochemical behavior
Abstract Cholesterol reacts under Appel conditions (CBr4/PPh3) to give 3,5-cholestadiene (elimination) and 3β-bromocholest-5-ene (substitution with retention of configuration). Thus, the bromination of cholesterol deviates from the stereochemistry of the standard Appel mechanism due to participation of the Δ5 π-electrons. In contrast, the subsequent azidolysis (NaN3/DMF) of 3β-bromocholest-5-ene proceeds predominantly by Walden inversion (SN2) affording 3α-azidocholest-5-ene. The structures of all relevant products were revealed by X-ray single crystal structure analyses, and the NMR data are in ag...
Source: Beilstein Journal of Organic Chemistry - January 27, 2023 Category: Chemistry Authors: Beilstein Journal of Organic Chemistry - Syndicated Feeds Tags: Appel reaction azidolysis cholesterol crystal structure Walden inversion Full Research Paper Source Type: research

Organophosphorus chemistry: from model to application
Beilstein J. Org. Chem. 2023, 19, 89–90. doi:10.3762/bjoc.19.8 (Source: Beilstein Journal of Organic Chemistry)
Source: Beilstein Journal of Organic Chemistry - January 25, 2023 Category: Chemistry Authors: Beilstein Journal of Organic Chemistry - Syndicated Feeds Tags: organophosphorus chemistry Editorial Source Type: research

Preparation of β -cyclodextrin/polysaccharide foams using saponin
Abstract Cyclodextrins, cyclic oligosaccharides with a hydrophobic cavity that form inclusion complexes with nonpolar molecules, can be used to functionalize other polysaccharides. Xanthan gum, locust bean gum or chitosan can be crosslinked using citric acid in the presence of β-cyclodextrin to produce insoluble matrices. In this work, polymeric foams based on those polysaccharides and saponin have been prepared using a green synthesis method to increase the porosity of the matrices. The saponin of soapbark (Quillaja saponaria) has been used to obtain foams using different procedures. The influence of the synthesis pa...
Source: Beilstein Journal of Organic Chemistry - January 24, 2023 Category: Chemistry Authors: Beilstein Journal of Organic Chemistry - Syndicated Feeds Tags: chitosan cyclodextrin polymers green synthesis locust bean gum saponin sorption xanthan gum Full Research Paper Source Type: research

Catalytic aza-Nazarov cyclization reactions to access α -methylene- γ -lactam heterocycles
Abstract We have developed a catalytic aza-Nazarov reaction of N-acyliminium salts generated in situ from the reaction of a variety of cyclic and acyclic imines with α,β-unsaturated acyl chlorides to afford substituted α-methylene-γ-lactam heterocycles. The reactions proceed effectively in the presence of catalytic (20 mol %) amounts of AgOTf as an anion exchange agent or hydrogen-bond donors such as squaramides and thioureas as anion-binding organocatalysts. The aza-Nazarov cyclization of 3,4-dihydroisoquinolines with α,β-unsaturated acyl chlorides gives tricyclic lactam products 7 in up to 7...
Source: Beilstein Journal of Organic Chemistry - January 17, 2023 Category: Chemistry Authors: Beilstein Journal of Organic Chemistry - Syndicated Feeds Tags: α -methylene- γ -lactam aza-Nazarov reaction β -silicon effect heterocycles intramolecular cyclization Full Research Paper Source Type: research