Dual Function of -Iodosuccinimide for C(sp)-B Bond Activation.

A practical method for C(sp)-B bond activation was developed. Using a combination of alkyl trifluoroborates and -iodosuccinimide (NIS), various C(sp)-heteroatom bonds were readily generated in an efficient manner. Mechanistic studies revealed the bifunctional ability of NIS: mediating the formation of reactive halogenated intermediates and activating them via halogen bonding.

A Unified Synthetic Strategy to Introduce Heteroatoms via Electrochemical Functionalization of Alkyl Organoboron Reagents.

Based on systematic electrochemical analysis, an integrated synthetic platform of C(sp)-based organoboron compounds was established for the introduction of heteroatoms. The electrochemically mediated bond-forming strategy was shown to be highly effective for the functionalization of sp-hybridized carbon atoms with significant steric hindrance. Moreover, virtually all the nonmetallic heteroatoms could be utilized as reaction partners using one unified protocol.

Revisiting Thin-Layer Electrochemistry in a Chip-Type Cell for the Study of Electro-organic Reactions.

It is important but challenging to elucidate the electrochemical reaction mechanisms of organic compounds using electroanalytical methods. Particularly, a rapid and straightforward method that provides information on reaction intermediates or other key electrochemical parameters may be useful. In this work, we exploited the advantages of classic thin-layer electrochemistry to develop a thin-layer electroanalysis microchip (TEAM).

Modular Counter-Fischer-Indole Synthesis through Radical-Enolate Coupling.

A single-electron transfer mediated modular indole formation reaction from a 2-iodoaniline derivative and a ketone has been developed. This transition-metal-free reaction shows a broad substrate scope and unconventional regioselectivity trends. Moreover, important functional groups for further transformation are tolerated under the reaction conditions.

Cobalt-Rhodium Heterobimetallic Nanoparticle-Catalyzed N-Alkylation of Amines with Alcohols to Secondary and Tertiary Amines.

Without the requirement for base or other additives, CoRh/C can selectively catalyze both mono- and bis-N-alkylation through the coupling of simple alcohols with amines, yielding a range of secondary and tertiary amines in good to excellent isolated yields. The reaction can be applied to benzyl alcohol with optically active 1-phenylethan-1-amines, and secondary amines were isolated in quantitative yields with an excellent enantiomeric excess (ee > 94%). Selectivity is achieved by varying the reaction temperature and amount of catalyst used.

Active and Recyclable Catalytic Synthesis of Indoles by Reductive Cyclization of 2-(2-Nitroaryl)acetonitriles in the Presence of Co-Rh Heterobimetallic Nanoparticles with Atmospheric Hydrogen under Mild Conditions.

A cobalt-rhodium heterobimetallic nanoparticle-catalyzed reductive cyclization of 2-(2-nitroaryl)acetonitriles to indoles has been achieved. The tandem reaction proceeds without any additives under the mild conditions (1 atm H and 25 °C). This procedure could be scaled up to the gram scale.

The farnesyltransferase inhibitor, LB42708, inhibits growth and induces apoptosis irreversibly in H-ras and K-ras-transformed rat intestinal epithelial cells.

LB42708 (LB7) and LB42908 (LB9) are pyrrole-based orally active farnesyltransferase inhibitors (FTIs) that have similar structures. The in vitro potencies of these compounds against FTase and GGTase I are remarkably similar, and yet they display different activity in apoptosis induction and morphological reversion of ras-transformed rat intestinal epithelial (RIE) cells. Both FTIs induced cell death despite K-ras prenylation, implying the participation of Ras-independent mechanism(s).

Hydantoin derivatives as non-peptidic inhibitors of Ras farnesyl transferase.

1,3,5,5-Tetrasubstituted 2,4-imidazolinedione (hydantoin) derivatives were evaluated as Ftase inhibitors. Potent Ftase inhibitors without thiol or peptide were obtained in three steps.

Dendritic oligoguanidines as intracellular translocators.

A series of polyguanidylated dendritic structures that can be used as molecular translocators have been designed and synthesized based on nonpeptide units. The dendritic oligoguanidines conjugated with fluorescein or with a green fluorescent protein (GFP) mutant as cargos were isolated and characterized. Quantification and time-course analyses of the cellular uptake of the conjugates using HeLa S3 and human cervical carcinoma cells reveal that the polyguanidylated dendrimers have comparable translocation efficiency to the Tat(49-57) peptide.

Characterization of a novel cyclin-dependent kinase 1 inhibitor, BMI-1026.

Cyclin-dependent kinases (Cdks) have been attractive targets for the development of anticancer therapeutic agents. In an effort to generate a new class of anti-Cdk inhibitors, we synthesized aryl aminopyrimidines and examined the effect of these compounds in both in vitro kinase assays and cultured cells. Two of these compounds, BMI-1026 and BMI-1042, induced a strong cell cycle alteration with potent inhibitory activities against cyclin-dependent kinases, collectively known as Cdks.