A novel procedure for the preparation of biaryl compounds by Pd-catalyzed homocoupling of N'-tosyl arylhydrazine has been described. N'-Tosyl arylhydrazine, as a readily available and stable coupling partner, demonstrated its generality in the homocoupling reactions. The scope of the reaction and possible mechanism have also been investigated.

The design, synthesis and biological activities of potent pyrazole-based tricyclic CB1 receptor antagonists (2) are described. The key synthetic step involves the ring closure of the lithiated alpha, gamma-keto ester adduct (4). The optimal nitroderivative (28) in this series exhibits a high CB1 receptor affinity (pKi=7.2) as well as very potent antagonistic activity (pA2=8.8) in vitro. The reg...

A novel and simple HCl-mediated, photocatalytic method for quinoxaline(on)es C3-H arylation with arylhydrazine under transition metal catalyst- oxidant-free conditions is presented. Various underwent this transformation smoothly, demonstrating a broad substrate tolerance providing the corresponding aryl products in moderate to excellent yields. Mechanistic studies indicated that radical pathway...

It has long been known that pyrazole and fused pyrazole compounds possess numerous chemical, biological, medicinal and agricultural applications because of their versatile biological activities appearing as antimicrobial, antiviral, antitumor, anti-inflammatory, antihistaminic, pesticidal, antifungal and antipyretic agents. On the other hand, cyclic oxalyl compounds of type 1 have been used suc...

During the past several years, reports have appeared concerning the separation and characterization of a variety of newly recognized nonprotein amino acids of plant origin (2-6). A number of these substances have been identified as derivatives of glutamine in which substitution by residues other than those represented by the common a-amino acids has occurred at the amide nitrogen atom (6-13). I...

Reactions of dioxoosmium(VI) porphyrins [Os(VI)(Por)O(2)] with excess 1,1-diphenylhydrazine in tetrahydrofuran at ca. 55 degrees C for 15 min afforded bis(hydrazido(1-))osmium(IV) porphyrins [Os(IV)(Por)(NHNPh(2))(2)] (1a, Por = TPP (meso-tetraphenylporphyrinato dianion); 1b, Por = TTP (meso-tetrakis(p-tolyl)porphyrinato dianion)), hydroxo(amido)osmium(IV) porphyrins [Os(IV)(Por)(NPh(2))(OH)] (...

This work described a simple and efficient synthesis of dialkyl 3-(alkylamino)-1-aryl-1H-pyrazole-4,5-dicarboxylates via a three component reaction between arylhydrazine, alkylisocyanid and dialkylacetylenedicarboxylates in the presence of phenylisocyanate and α-Fe2O3 nanoparticles. Eco friendly, solvent-free conditions, excellent yields, and short reaction times, inexpensive and readily availa...