A novel series of chalcones, pyrimidines and imidazolinone is described; chalcones (4a-o) were prepared from the lead molecule 4-[2-(5-ethylpyridin-2-yl)ethoxy]benzaldehyde. Pyrimidine (5a-o) derivatives were prepared from the reaction of chalcones and guanidine nitrate in alkali media. Imidazolinones (6a-o) were synthesized from reaction of pyrimidine and oxazolone derivatives (prepared by Erl...

Barium salts of dibenzylidene cystines 8a-c were obtained from the reaction of Lcystine with benzaldehyde or its derivatives in the presence of barium hydroxide. Their reduction with zinc and hydrochloric acid in methanol yielded the Narylmethylcysteines ?9a-c?. These can, in turn, be converted by esterification into the methyl esters ?10 a-c. ?Reaction of N, N'-carbonyl diimidazole (Im C...

The fundamentals of Pd-catalyzed Csp2−Csp2 Miyaura borylation, Suzuki cross-coupling, and Stille cross-coupling reactions for a variety borylated precursors based on phenothiazine (PTZ), phenoxazine (POZ), carbazole (Cz), quinoxaline (QX) units have been explored. Three palladium-based catalysts were chosen this study: Pd(PPh3)4, Pd(PPh3)2Cl2, Pd(dppf)Cl2, applying different reaction conditions...

polyphenol oxidase (ppo), also known as tyrosinase (ec 1.14.18.1), is a copper-containing enzyme widely distributed in microorganisms, animals, and plants. this enzyme is responsible not only for browning in plants but also for melanization in animals. thus, tyrosinase inhibitors have a huge impact on industry and the economy. in the current study, we first purified the enzyme, then evaluated i...

Two new symmetrical Schiff bases have been prepared by the condensation of ethylenediamine and two benzaldehyde derivatives, 2-hydroxybenzaldehyde and 2,4-dimethoxybenzaldehyde. The electronic transitions within these Schiff bases molecules in chloroform solvent have been investigated by UV-Vis spectroscopy. The 1H NMR and IR spectra were studied and assigned to related groups. Furthermore,...

Bisimine and bisamine AB2 monomers have been synthesized from 3,5-diaminobenzoic acid and benzaldehyde derivatives without the need for protective groups or purification. This monomer preparation is universal for various electron-donating and electron-withdrawing benzaldehyde substrates. To demonstrate the versatility of these previously unreported AB2 monomers in the formation of high molecula...

A family of α-aryl-α-aminophosphonates and α-aryl-α-aminophosphine oxides was synthesized by the microwave-assisted solvent-free addition of dialkyl phosphites and diphenylphosphine oxide, respectively, to imines formed from benzaldehyde derivatives and primary amines. After optimization, the reactivity was mapped, and the fine mechanism was evaluated by DFT calculations. Two α-aminophosphonate...

Gold-catalyzed syntheses of 2,3-disubstituted indole derivatives from N-hydroxyanilines and allenes are described; these reactions require benzaldehyde as an additive to generate nitrones in situ. Our control experiments indicate that nitrones and water were indispensable in the reactions whereas N-hydroxyanilines alone were inactive nucleophiles. This synthetic method is compatible with allene...