Nucleophilic ring-opening reaction of benzoxazinones—access to o-amino-2,2,2-trifluoroacetophenones

Electron-Deficient Fluoroarene-Mediated Synthesis of Trifluoromethyl Ketones from Carboxylic Acids

Fluoroarene-mediated trifluoromethylation of carboxylic acids for the synthesis of trifluoromethyl ketones is disclosed. The fluoroarene activates the acid group and generates the fluoride source in situ for the trifluoromethylation reaction. The present protocol is safe and metal-free, operates under mild reaction conditions, and does not require any external additives to generate trifluoromethyl anion. The current transformation provides good functional group tolerance and also delivers 92% and 88% yields of trifluoromethyl ketones in batch and continuous flow, respectively.

Trifluoromethylation of Benzoic Acids: An Access to Aryl Trifluoromethyl Ketones

The trifluoromethylation of benzoic acids with TMSCF₃ was achieved through nucleophilic substitution with the use of anhydrides as an in situ activating reagent. Under the reaction conditions, a wide range of carboxylic acids including the bioactive ones worked well, thus providing a facile and efficient method for preparing aryl trifluoromethyl ketones from the readily available starting materials.

Recyclable Heterogeneous Palladium-Catalyzed Cyclocarbonylation of 2-Iodoanilines with Acyl Chlorides in the Biomass-Derived Solvent 2-Methyltetrahydrofuran

A highly efficient, green palladium-catalyzed cyclocarbonylation of 2-iodoanilines with acyl chlorides has been developed that proceeds smoothly in a biomass-derived solvent 2-methyltetrahydrofuran with N,N-diisopropylethylamine as base at 100 °C under 20 bar of carbon monoxide using an 2-aminoethylamino-modified MCM-41-anchored palladium acetate complex [2N-MCM-41-Pd(OAc)₂] as a heterogeneous catalyst, yielding a wide variety of 2-substituted 4H-3,1-benzoxazin-4-one derivatives in good to excellent yields. This supported palladium catalyst could be facilely obtained by a two-step procedure from easily available starting materials and readily recovered via a simple filtration process and recycled at least 8 times without any apparent decrease in catalytic efficiency. The developed methodology not only avoids the use of toxic solvents such as tetrahydrofuran and dimethylformamide but also solves the basic problem of expensive palladium catalyst recovery and reuse and prevents effectively palladium contamination of the desired product.

New Quinazoline-Sulfonylurea Conjugates: Design, Synthesis and Hypoglycemic Activity

BACKGROUND

Sulphonylureas are the oldest and commonly used to treat diabetic patients, but its efficacy declines by time. It was reported that quinazoline nucleus exhibits a potent hypoglycemic effect in diabetic animal models.

OBJECTIVE

The current study aimed to synthesize new quinazoline-sulfonylurea conjugates and evaluate their hypoglycemic effects in alloxan-induced diabetic rats.

METHODS

The conjugates were synthesized by bioisosteric replacement of 5-chloro-2-methoxybenzamide moiety in glibenclamide or 1,3-dioxo-3,4-dihydroisoquinoline moiety in gliquidone with 6,7-dimethoxy-4-oxoquinazoline moiety (compounds 4a-4d, 9b-9c and 10b-10d). Diabetes was induced in rats by a single i.p. administration of alloxan, followed by treatment with the synthesized conjugates (5mg/kg Body weight).

RESULTS

All conjugates showed hypoglycemic effects with different efficacy indicated by the reduction in blood glucose and elevation of insulin levels. Moreover, these conjugates up-regulated the expression of pancreatic glucose transporter 2, muscle glucose transporter 4, and insulin receptor substrate-1 genes, compared to the diabetic group. A normal pancreatic tissue pattern was noticed in diabetic rats treated with compounds 9b, 9c, and 10c.

CONCLUSION

Conjugation of sulfonylurea with quinazoline (especially 9b, 9c, 10c) possessed a significant hypoglycemic effect through improving blood insulin level and insulin action and consequently increased the glucose uptake by the skeletal muscles.

1-(2-Amino-5-chlorophenyl)-2,2,2-trifluoroethan-1-one

In the title compound, C8H5ClF3NO, the F—C—C=O grouping shows a syn conformation [torsion angle = 1.1 (3)°] and an intramolecular N—H...O hydrogen bond generates an S(6) ring. In the crystal, N—H...F and N—H...O hydrogen bonds link the molecules into [010] chains.

Synthesis, insecticidal activity, structure–activity relationship (SAR) and density functional theory (DFT) of novel anthranilic diamides analogs containing 1,3,4-oxadiazole rings

A series of anthranilic diamides analogs (5a–x) containing 1,3,4-oxadiazole rings were synthesized, and their insecticidal activities were evaluated. The density functional theory (DFT) studies was used to understand the various insecticidal activities.