Sulfonylamidation of alkylbenzenes at benzylic position with p-toluenesulfonamide and 1,3-diiodo-5,5-dimethylhydantoin

PhI(OAc)2 and iodine-mediated synthesis of N-alkyl sulfonamides derived from polycyclic aromatic hydrocarbon scaffolds and determination of their antibacterial and cytotoxic activities

The development of new approaches toward chemo- and regioselective functionalization of polycyclic aromatic hydrocarbon (PAH) scaffolds will provide opportunities for the synthesis of novel biologically active small molecules that exploit the high degree of lipophilicity imparted by the PAH unit. Herein, we report a new synthetic method for C-X bond substitution that is speculated to operate via a N-centered radical (NCR) mechanism according to experimental observations. A series of PAH sulfonamides have been synthesized and their biological activity has been evaluated against Gram-negative and Gram-positive bacterial strains (using a BacTiter-Glo assay) along with a series of mammalian cell lines (using CellTiter-Blue and CellTiter-Glo assays). The viability assays have resulted in the discovery of a number of bactericidal compounds that exhibit potency similar to other well-known antibacterials such as kanamycin and tetracycline, along with the discovery of a luciferase inhibitor. Additionally, the physicochemical and drug-likeness properties of the compounds were determined experimentally and using in silico approaches and the results are presented and discussed within.

Synthesis and identification of heteroaromatic N-benzyl sulfonamides as potential anticancer agents

Sulfonamides are a crucial class of bioisosteres that are prevalent in a wide range of pharmaceuticals, however, the available methods for their production directly from heteroaryl aldehyde reagents remains surprisingly limited. A new approach for regioselective incorporation of a sulfonamide unit to heteroarene scaffolds has been developed and is reported within. As a result, a variety of primary benzylic N-alkylsulfonamides have been prepared via a two-step (one pot) formation from the in situ reduction of an intermediate N-sulfonyl imine under mild, practical conditions. The compounds have been screened against a variety of cell lines for cytotoxicity effects using a Cell Titer Blue assay. The cell viability investigation identifies a subset of N-benzylic sulfonamides derived from the indole scaffold to be targeted for further development into novel molecules with potential therapeutic value. The most cytotoxic of the compounds prepared, AAL-030, exhibited higher potency than other well-known anticancer agents Indisulam and ABT-751.

Catalytic Halogen Bond Activation in the Benzylic C-H Bond Iodination with Iodohydantoins

This letter presents the side-chain iodination of electron-deficient benzylic hydrocarbons at rt using N-hydroxyphthalimide (NHPI) as radical initiator and 1,3-diiodo-5,5-dimethylhydantoin and 3-iodo-1,5,5-trimethylhydantoin (3-ITMH) as iodine source. Addition of a carboxylic acid increased the reactivity due to complex formation with and activation of 3-ITMH by proton transfer and halogen bond formation. No S_EAr reactions were observed under the employed reaction conditions. Our method enables convenient product isolation and gives 50-72% yields of isolated products.

Metal-free C-H amination of unactivated hydrocarbons with sulfonylimino-λ(3)-bromanes generated in situ from (diacetoxybromo)benzene

A simple method for direct metal-free C-H amination of unactivated hydrocarbons using easy-handling diacetoxy-λ(3)-bromane and triflylamide or sulfamate esters was developed. The high 2°/3° regioselectivities and deuterium isotope effects suggest a concerted organonitrenoid transition state, analogous to C-H amination with N-triflylimino-λ(3)-bromane.

Convenient synthesis of α,β-unsaturated γ-butyrolactones and γ-butyrolactams via decarboxylative iodination of paraconic acids and β-carboxyl-γ-butyrolactams using 1,3-diiodo-5,5-dimethylhydantoin

A convenient synthetic approach to α,β-unsaturated γ-butyrolactones and γ-butyrolactams is reported.

Selective intermolecular amination of C-H bonds at tertiary carbon centers

C-H insertion: A method for intermolecular amination of tertiary CH bonds is described that uses limiting amounts of substrate and a convenient phenol-derived nitrogen source. Structure-selectivity and mechanistic studies suggest that steric interaction between the substrate and active oxidant is the principal determinant of product selectivity.