The design, synthesis, and development of a new class of modular, strongly basic, and tunable bifunctional Brønsted base/H-bond-donor organocatalysts are reported. These catalysts incorporate a triaryliminophosphorane as the Brønsted basic moiety and are readily synthesized via a last step Staudinger reaction of a chiral organoazide and a triarylphosphine. Their application to the first general...

This research includes synthesis of new derivatives benzimidazole , the compound (A1*) prepared by reaction o-phenylene diamine with carbon disulfide in alcoholic potassium hydroxide. Then was ethyl chloroacetate and hydroxide to give ester (A2*). preparation hydrazide (A3*) (A2*) hydrazine hydrate (80%). we used prepare pyrazole (A4), then mannich basses (A4) different primary aromatic amines ...

In this study, a series of isatin-based Mannich bases were prepared and their biological activity was evaluated. Schiff bases of isatin were synthesized by condensation of the keto group of isatin with different aromatic primary amines. The NMannich bases of the above Schiff bases were synthesized by reaction of the acidic imino group of isatin with formaldehyde and secondary amine. The chemica...

3-Aminomethylation of salicylalkylamides afforded hybrids with a Mannich base. In addition, it triggered the rotation of the amide bond. The observed conformational switch is driven by strong intramolecular hydrogen bonding between the Mannich base and phenolic group. Crystal structure analysis reveals the stabilization of the hybrid molecules by double hydrogen bonding of the phenolic OH, whic...

The use of 4-amino-5-benzyl-4H-[1,2,4]triazole-3-thiol (1) as a precursor to synthesize some new biologically active heterocycles has been found to be effective. Condensation of 1 with appropriate aldehydes gave the new Schiff bases 2a, b, which either by cyclization with thioglycolic acid gave 3a, b, or by Mannich reaction using morpholine gave 4a, b. Reaction of 1 with different halogen compo...

A novel Mannich-modified imidazoline (MMI) as cationic emulsifier was synthesised for corrosion harm reduction, through three steps — acylation, cyclization, and Mannich reaction. The surface activity was characterized by determination of surface tensions and critical micelle concentration (CMC). The corrosion inhibition performance of five types of steels in the simulated corrosion solution in...

Mannich bases are generally formed by the reaction between formaldehyde, a secondary amine and a compound containing reactive hydrogen atoms. They display varied biological activities such as antimicrobial [1], cytotoxic [2,3], anticancer [2], analgesic [4], anti-inflammatory [5] and anticonvulsant [6] and DNA topoisomerase I inhibiting activities [3]. In this study, it was planned to synthesiz...

BACKGROUND The results presented herein show that the cyclic aminal (2S,7R,11S,16R)-1,8,10,17-tetraazapentacyclo[8.8.1.1.(8,17)0.(2,7)0(11,16)]icosane (6), derived from cis-(meso)-1,2-diaminocyclohexane and formaldehyde, is a suitable substrate for the preption of a series of cis-meso Mannich bases such as 8a-l by reaction with p-substituted phenols 7a-l in basic media. These compounds are valu...