Synergistic Pd/Ni Dual-Catalyzed Cross-Coupling of Azaaryl Acetates with -Difluorinated Cyclopropanes.

We herein report the development of a novel Pd/Ni dual-catalyzed ring-opening functionalization of -difluorinated cyclopropanes (-FCPs) with azaaryl acetates. This bimetallic catalytic strategy streamlines the diversity-oriented synthesis (DOS) of α-quaternary 2-fluoroallylic azaaryl acetates with features of a broad scope and excellent functional group tolerance, which enables the efficient late-stage transformation of natural product-derived -FCPs. The resulting α-quaternary azaaryl acetates could serve as a valuable platform to prepare other different fluoroallylic azaaryl scaffolds.

Discovery of New Anti-MRSA Agents Based on Phenoxyethanol and Its Mechanism.

Methicillin-resistant (MRSA) poses a severe threat to public health and safety. The discovery and development of novel anti-MRSA drugs with a new mode of action are a challenge. In this study, a class of novel aryloxyethyl propiolates and their homologues as anti-MRSA agents have been designed and synthesized based on phenoxyethanol, of which compound showed high inhibitory activity against MRSA with an MIC of 0.

Modular Approach for Diversity-Oriented Synthesis of β-Fluoroalkylated Arenes via Pd/Norbornene Cooperative Catalysis.

A novel approach towards the efficient assembly of β-fluoroalkylated arenes is presented here based on Pd/norbornene cooperative catalysis, which features an excellent functional group tolerance, as well as a broad ipso termination scope. The mild reaction conditions enabled the diversity-oriented synthesis (DOS) of the 13 and 14-membered fluorinated macrolactones which is extremely challenging otherwise. This new abstract could be used instead of our old version.

Synthesis of novel 2-methyl-3-furyl sulfide flavor derivatives as efficient preservatives.

Foodborne microbial infestation seriously threatens food security, and the development of low-risk food preservatives is highly needed in food production. For discovering novel flavor molecules with antiseptic function, novel 2-methyl-3-furyl sulfide flavor derivatives were synthesized and evaluated. A wide range of 2-methyl-3-furyl sulfide derivatives were synthesized by reactions of 2-methyl-3-furyl disulfide with cyclic ethers, amides, ketones, and epoxides.

Diversity-Oriented Synthesis of Fluoromethylated Arenes via Palladium-Catalyzed C-H Fluoromethylation of Aryl Iodides.

Herein we report the first versatile and expeditious method for the site-selective C-H fluoromethylation of aryl iodides via Pd/norbornene cooperative catalysis, which could work as a robust toolbox for the diversity-oriented synthesis (DOS) of fluoromethylated arenes. This methodology features the use of the low-cost industrial raw material CHIF as the fluoromethyl source, an excellent functional group tolerance, and a broad termination scope and can be expanded to the late-stage modification of biorelevant molecules.

Functional Application of Sulfur-Containing Spice Compounds.

Sulfur-containing spice compounds possess diverse biological functions and play an important role in food, chemicals, pharmaceuticals, and agriculture. The development of functional spices has become increasingly popular, especially for medicinal functions for dietary health. Thus, this review focuses on the properties and functions of sulfur-containing spice compounds, including antioxidant, anti-inflammatory, antiobesity, anticancer, antibacterial, and insecticidal functions, among others.

Synthesis and bioactivity of phenyl substituted furan and oxazole carboxylic acid derivatives as potential PDE4 inhibitors.

In this present study, a series of 5-phenyl-2-furan and 4-phenyl-2-oxazole derivatives were designed and synthesized as phosphodiesterase type 4 (PDE4) inhibitors. In vitro results showed that the synthesized compounds exhibited considerable inhibitory activity against PDE4B and blockade of LPS-induced TNF-α release. Among the designed compounds, Compound 5j exhibited lower IC value (1.

Selective C-H dithiocarbamation of arenes and antifungal activity evaluation.

This paper discloses a transition metal-free selective C-H dithiocarbamation of drug skeletons using disulfiram (DSF) in the presence of KI/K2S2O8 in DMF/H2O. Drug skeletons, including 5-aminopyrazoles, indoles, pyrroloquinoline, and Julolidine, underwent C-H dithiocarbamation smoothly to afford a variety of drug-like molecules in moderate to good yields. It was found that the in situ formed 5-aminopyrazole iodide is the key intermediate for the dithiocarbamation.

Synthesis and biological evaluation of 1,3,4-thiadiazole derivatives as type III secretion system inhibitors against Xanthomonas oryzae.

Xanthomonas oryzae pv. oryzae (Xoo) infection directly leads to a severe disease known as leaf blight, which is a major cause of yield loss of rice. Use of traditional bactericides has resulted in severe resistance in pathogenic bacteria.

Synthesis and fungicidal activity of novel pyrazole derivatives containing 5-Phenyl-2-Furan.

Pyrazole constitutes an important heterocyclic family covering a broad range of synthetic as well as natural products that exhibit numerous chemical, biological, agrochemical and pharmacological properties. In order to explore compounds with good fungicidal activity, a series of new pyrazole derivatives containing 5-phenyl-2-furan were designed and synthesized. In vitro and in vivo fungicidal activities were evaluated and the compound ethyl-1-(5-phenylfuran-2-carbonyl)-5-propyl-1H-pyrazole-3-carboxylate (I8) displayed significant fungicidal activity against various fungi, especially against P.

Direct thiocarbamation of imidazoheterocycles via dual C-H sulfurization.

A copper-catalyzed DTBP oxidative dual C-H sulfurization has been developed for the direct thiocarbamation of imidazopyridines using a combination of elemental sulfur and formamides as carbamothioyl surrogates. NBS (bromo succinimide) was found to promote the thiocarbamation in good yields. This dual C-H sulfurization strategy enables access to a wide range of carbamothioyl imidazoheterocycles without the use of highly toxic phosgene.

Synthesis and bioactivity of 1,3-thiazolidine-2-thione derivatives against type III secretion system of Xanthomonas oryzae.

Targeting virulence factors of bacterial without affecting their growth and survival, has been an initiative strategy for the development of novel anti-microbial agents. The type III secretion system (T3SS), one of essential and highly conserved virulence factors in most Gram-negative pathogenic bacteria, has been regarded as an effective target that developed new anti-microbial drugs. Xanthomonas oryzae pv.

Iodine-promoted radical alkyl sulfuration of imidazopyridines with dialkyl azo compounds and elemental sulfur.

Dialkyl azo compounds were found to be effective alkyl radical sources for direct alkyl sulfuration with imidazopyridines using elemental sulfur under metal-free conditions. Iodine, an inexpensive and mild reagent, could promote alkyl sulfuration. A variety of quaternary cyanoalkyl radicals were successfully coupled with elemental sulfur.

DMSO-mediated palladium-catalyzed cyclization of two isothiocyanates C-H sulfurization: a new route to 2-aminobenzothiazoles.

DMSO was found to activate arylisothiocyanates for self-nucleophilic addition. A subsequent intramolecular C-H sulfurization catalyzed by PdBr enables access to a wide range of 2-aminobenzothiazole derivatives in moderate to good yields. This is the first example of a DMSO-mediated Pd-catalyzed synthesis of 2-aminobenzothiazoles through cyclization/C-H sulfurization of two isothiocyanates.

Sulfite-Promoted Synthesis of N-Difluoromethylthioureas via the Reaction of Azoles with Bromodifluoroacetate and Elemental Sulfur.

A sulfite-promoted transformation of azoles into N-difluoromethylthioureas through N-difluoromethylation and sulfuration has been developed. In this reaction, inexpensive ethyl bromodifluoroacetate and nontoxic elemental sulfur were used as the difluoromethylation and sulfuration reagents, respectively. A variety of azoles, including benzimidazoles, imidazoles, and triazoles, performed well to afford a broad range of azole thioureas in moderate to good yields.

HFIP-Promoted Bischler Indole Synthesis under Microwave Irradiation.

1,1,1,3,3,3-Hexafluoropropan-2-ol (HFIP) was found to be effective for the Bischler indole synthesis under microwave irradiation in the absence of a metal catalyst. Under the catalysis of HFIP, a wide range of α-amino arylacetones were successfully transformed into indole derivatives with moderate to good yields.

Remote C-H Activation of Various N-Heterocycles Using a Single Template.

A single and simple ortho-sulfonyl benzonitrile template was developed to achieve remote C-H olefination of six different classes of N-heterocycles. We demonstrate that, by varying precatalysts and conditions, the same template can be applied to the remote C-H activation of six structurally distinct heterocyclic scaffolds, and the site-selectivity can be predicted based on distance and geometry. Furthermore, this new development shows that template-directed remote C-H activation is possible through macrocyclopalladation processes with smaller ring sizes.

Oxidative dual C-H thiolation of imidazopyridines with ethers or alkanes using elemental sulphur.

Dual C-H thiolation reactions using elemental sulphur remain a challenge. This communication discloses an oxidative radical dual sp/sp C-H thiolation strategy for the coupling of imidazopyridines with ethers or alkanes using elemental sulphur.

Isothiocyanation of amines using the Langlois reagent.

The Langlois reagent was found to be effective for the isothiocyanation of primary amines in the presence of copper iodide and diethyl phosphonate.

Palladium-catalyzed oxidative carbamoylation of isoquinoline N-oxides with formylamides by means of dual C-H oxidative coupling.

A new palladium-catalyzed oxidative carbamoylation reaction of isoquinoline N-oxides with formylamides for the synthesis of isoquinoline-1-carboxamides is established. The method represents the first example of the carbamoylation of isoquinoline N-oxides with formylamides to furnish arylamides using the dual C-H oxidation strategy.

Copper-catalyzed ring expansion of 2-aminobenzothiazoles with alkynyl carboxylic acids to 1,4-benzothiazines.

A new ring expansion of 2-aminobenzothiazoles with alkynyl carboxylic acids was developed, which allows for one-pot synthesis of 1,4-benzothiazines in moderate to excellent yields. The cascade reaction was achieved through decarboxylative coupling, nucleophilic ring-opening reaction and intramolecular hydroamination process.

A novel Pd-catalyzed N-dealkylative carbonylation of tertiary amines for the preparation of amides.

A novel and convenient protocol for the formation of amides via palladium-catalyzed N-dealkylative carbonylation of alkyl tertiary amines has been developed. In the presence of PdCl2(PhCN)2, CuO, PhCN and CO, a range of substituents on both aryl iodides and alkyl tertiary amines were compatible with the reaction to afford a series of N,N-disubstituted amides in moderate to excellent yields.

Pd(II)-catalyzed meta-C-H olefination, arylation, and acetoxylation of indolines using a U-shaped template.

meta-C-H olefination, arylation, and acetoxylation of indolines have been developed using nitrile-containing templates. The combination of a monoprotected amino acid ligand and the nitrile template attached at the indolinyl nitrogen via a sulfonamide linkage is crucial for the meta-selective C-H functionalization of electron-rich indolines that are otherwise highly reactive toward electrophilic palladation at the para-positions. A wide range of synthetically important and advanced indoline analogues are selectively functionalized at the meta-positions.

Conformation-induced remote meta-C-H activation of amines.

Achieving site selectivity in carbon-hydrogen (C-H) functionalization reactions is a long-standing challenge in organic chemistry. The small differences in intrinsic reactivity of C-H bonds in any given organic molecule can lead to the activation of undesired C-H bonds by a non-selective catalyst. One solution to this problem is to distinguish C-H bonds on the basis of their location in the molecule relative to a specific functional group.