Synthesis of optically active α-aminobenzolactam via an oxidative–cyclization reaction

Synthesis of Benzannulated Medium-ring Lactams via a Tandem Oxidative Dearomatization-Ring Expansion Reaction

Medium-ring natural products exhibit diverse biological activities but such scaffolds are underrepresented in probe and drug discovery efforts due to the limitations of classical macrocyclization reactions. We report herein a tandem oxidative dearomatization-ring-expanding rearomatization (ODRE) reaction that generates benzannulated medium-ring lactams directly from simple bicyclic substrates. The reaction accommodates diverse aryl substrates (haloarenes, aryl ethers, aryl amides, heterocycles) and strategic incorporation of a bridgehead alcohol generates a versatile ketone moiety in the products amenable to downstream modifications. Cheminformatic analysis indicates that these medium rings access regions of chemical space that overlap with related natural products and are distinct from synthetic drugs, setting the stage for their use in discovery screening against novel biological targets.

Construction of N-containing heterocycles via oxidative intramolecular N–H/X–H coupling

The preparation of N-containing heterocycles using oxidative coupling has become a hot topic recently. This feature article summarized the methodology related to the construction of N-heterocycles through intramolecular oxidative N–H/X–H coupling.

Discovery of a novel class of benzazepinone Na(v)1.7 blockers: potential treatments for neuropathic pain

A series of benzodiazepines and benzazepinones were synthesized and evaluated as potential sodium channel blockers in a functional, membrane potential-based assay. One member of the benzazepinone series, compound 47, displayed potent, state-dependent block of hNa(v)1.7, and was orally efficacious in a rat model of neuropathic pain.

Nitrenium ion azaspirocyclization-spirodienone cleavage: a new synthetic strategy for the stereocontrolled preparation of highly substituted lactams and N-hydroxy lactams

[reaction: see text] Although 1,4-cyclohexadienes 2, obtained through the Birch reduction of arenes 1, have found widespread use as masked beta-oxo carbonyl synthons 3, the possibility that 2,5-cyclohexadienones 5 might also be employed to the same end has been overlooked despite their ready availability. As part of our ongoing investigation of the synthetic chemistry of nitrenium ions, we have developed a novel and efficient strategy for the stereoselective preparation of di- and trisubstituted azetidinone, pyrrolidinone, and piperidinone derivatives, which features the ozonolytic cleavage of azaspirocyclic 2,5-cyclohexadienones 12. For example, ozonolysis of spirodienone 12c in CH2Cl2 and reductive workup with dimethyl sulfide generated unstable beta-formyl ester 21, whereas cleavage in MeOH followed by reduction with thiourea led to hemiacetal 22. While both 21 and 22 partially decompose upon exposure to silica gel, they can be trapped in situ, with a variety of weakly basic nucleophiles, to usefully substituted products. The requisite spirodienone substrates are readily accessible through the nitrenium ion cyclization of alkyl omega-arylhydroxamates 10, which proceeds with moderate to high diastereoselectivity.