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The synthesis of bench-stable α,α-bis(trimethylsilyl)toluenes and tris(trimethylsilyl)methane is described and their use in stereoselective Peterson olefinations has been achieved with a wide substrate scope. Product stereoselectivity was poor with carbonyl electrophiles ( E/ Z ∼1:1 to 4:1) though this was significantly improved by employing the corresponding substituted N-benzylideneaniline (up to 99:1) as an alternative electrophile. The olefination byproduct was identified as N, N-bis(trimethylsilyl)aniline and could be easily separated from product by aqueous acid extraction. Evidence for an autocatalytic cycle has been obtained. [ABSTRACT FROM AUTHOR]

Abstract: Control and prevention of tuberculosis is a major challenge, as one-third of the world’s population is infected with Mycobacterium tuberculosis. The resurgence of tuberculosis and the emergence of multidrug-resistance strains of mycobacteria, necessitate the search for new class of antimycobacterial agents. As a part of investigation of new antitubercular agents in this laboratory, we describe the syntheses of various hydrazides of comarins, quinolones and pyrroles and screening against M. tuberculosis (Mtb) H37Rv by using rifampin as a standard drug. Among the designed molecules, the most prominent compounds 2a–g, 4a and 9a showed >90% GI at MIC<6.25μg/mL. Finally, these studies suggests that compounds 2a–g, 4a and 9a may serve as promising lead scaffolds for further generation of new anti-TB agents. [Copyright &y& Elsevier]

Abstract: A small library of 2-indolinone derivatives with the 2,6-dichlorophenyl ring at the N1 position and with varying substitutions including aryl groups at the 3-position were synthesized, and their structures were confirmed by spectral analysis. All molecules were screened for their in vitro cytotoxic activity on SW620 colon cancer cell lines. Among the designed series compounds 4c, 4f and 4j were found to be active at concentrations of 2–15μg/ml. Some 3D-QSAR models were also built to understand the structure–activity relationship. [Copyright &y& Elsevier]

Peterson olefination as represented by the building facade is one of the historic yet still essential building blocks of synthetic chemistry. In their Communication on page 8737 ff., D. O'Shea et al. report on the first stereoselective aza ‐ Peterson reaction utilising bench stable geminal bis ‐ silane reagents with imine substrates. These advances have allowed several long ‐ standing limitations for this double bond forming reaction to be overcome. The facade itself is the entrance into the original building of the Royal College of Surgeons in Ireland which has housed the chemistry department since its foundation in 1828. [ABSTRACT FROM AUTHOR]