A Versatile Method for the Synthesis of Benzimidazoles from o-Nitroanilines and Aldehydes in One Step via a Reductive Cyclization

Cascade palladium catalysis: a predictable and selectable regiocontrolled synthesis of N-arylbenzimidazoles

By choice: The palladium-catalyzed cascade reaction of 2-chloroaryl sulfonates with arylamine and amide nucleophiles provides direct access to N-arylbenzimidazoles. This strategy selectively produces the heterocycles based on chemoselective oxidative addition. 2-Chloroaryl triflates (Tf) produce one regioisomer and the corresponding 2-chloroaryl mesylates (Ms) deliver the other in a selectable manner.

Boric Acid Catalyzed Convenient Synthesis of Benzimidazoles in Aqueous Media

Synthesis of benzimidazoles has been developed by theo-phenylenediamine with aldehydes using boric acid an efficient catalyst under mild reaction conditions in aqueous media. The product is applicable to aryl and heteroaryl aldehydes. This reaction led to the formation of benzimidazoles new derivatives in good yields. The FT-IR,19F-NMR,1H-NMR,13C-NMR spectra and elemental analysis confirm the structure of compounds.

Synthesis of benzimidazoles by PIDA-promoted direct C(sp2)-H imidation of N-arylamidines

A metal-free synthesis of diversified benzimidazoles from N-arylamidines through a phenyliodine(III) diacetate (PIDA) promoted intramolecular direct C(sp(2))-H imidation has been developed. The reaction proceeds smoothly at 0 °C or ambient temperature to provide the desired products in good to excellent yields. The synthesis of 2-alkyl- or 2-alkyl-fused benzimidazoles, which are generally inaccessible by similar Pd- or Cu-catalyzed approaches, can also be achieved.

Structure-activity relationship study of selective benzimidazole-based inhibitors of Cryptosporidium parvum IMPDH

Cryptosporidium parasites are important waterborne pathogens of both humans and animals. The Cryptosporidium parvum and Cryptosporidium hominis genomes indicate that the only route to guanine nucleotides is via inosine 5'-monophosphate dehydrogenase (IMPDH). Thus the inhibition of the parasite IMPDH presents a potential strategy for treating Cryptosporidium infections. A selective benzimidazole-based inhibitor of C. parvum IMPDH (CpIMPDH) was previously identified in a high throughput screen. Here we report a structure-activity relationship study of benzimidazole-based compounds that resulted in potent and selective inhibitors of CpIMPDH. Several compounds display potent antiparasitic activity in vitro.

Imidazole as a parent π-conjugated backbone in charge-transfer chromophores

Research activities in the field of imidazole-derived push-pull systems featuring intramolecular charge transfer (ICT) are reviewed. Design, synthetic pathways, linear and nonlinear optical properties, electrochemistry, structure-property relationships, and the prospective application of such D-π-A organic materials are described. This review focuses on Y-shaped imidazoles, bi- and diimidazoles, benzimidazoles, bis(benzimidazoles), imidazole-4,5-dicarbonitriles, and imidazole-derived chromophores chemically bound to a polymer chain.

Synthesis, characterization and ethylene oligomerization behavior of 2-benzoimidazol-8-ethoxyquinolylnickel dihalides

A series of 2-benzoimidazol-8-ethoxyquinolines (L1-L6) and the nickel dihalides thereof (C1-C12) were synthesized and characterized by elemental analysis and infrared spectroscopy. The molecular structures of representative complexes were determined by single crystal X-ray diffraction which revealed a distorted pyramidal geometry at nickel. All complexes, when activated with Et(2)AlCl, showed high activities towards ethylene oligomerization and enhanced thermodynamic stability.

Pyrazolo[3,4-d]pyrimidines as potent inhibitors of the insulin-like growth factor receptor (IGF-IR)

A high throughput screen of Abbott's compound repository revealed that the pyrazolo[3,4-d]pyrimidine class of kinase inhibitors possessed moderate potency for IGF-IR, a promising target for cancer chemotherapy. The synthesis and subsequent optimization of this class of compounds led to the discovery of 14, a compound that possesses in vivo IGF-IR inhibitory activity.