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This is the peer reviewed version of the following article: Deichert, J.A., Mizufune, H., Patel, J.J., Hurst, T.E., Maheta, A., Kitching, M.O., Ross, A.C. and Snieckus, V. (2020), Expedient Pd‐Catalyzed α‐Arylation towards Dibenzoxepinones: Pivotal Manske's Ketone for the Formal Synthesis of Cularine Alkaloids. Eur. J. Org. Chem.. doi:10.1002/ejoc.202000424, which has been published in final form at https://doi.org/10.1002/ejoc.202000424. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.

Mitochondrial fission is important in physiological processes, including coordination of mitochondrial and nuclear division during mitosis, and pathologic processes, such as the production of reactive oxygen species (ROS) during cardiac ischemia-reperfusion injury (IR). Mitochondrial fission is mainly mediated by dynamin-related protein 1 (Drp1), a large GTPase. The GTPase activity of Drp1 is essential for its fissogenic activity. Therefore, we aimed to identify Drp1 inhibitors and evaluate their anti-neoplastic and cardioprotective properties in five cancer cell lines (A549, SK-MES-1, SK-LU-1, SW 900, and MCF7) and an experimental cardiac IR injury model. Virtual screening of a chemical library revealed 17 compounds with high predicted affinity to the GTPase domain of Drp1. In silico screening identified an ellipticine compound, Drpitor1, as a putative, potent Drp1 inhibitor. We also synthesized a congener of Drpitor1 to remove the methoxymethyl group and reduce hydrolytic lability (Drpitor1a). Drpitor1 and Drpitor1a inhibited the GTPase activity of Drp1 without inhibiting the GTPase of dynamin 1. Drpitor1 and Drpitor1a have greater potency than the current standard Drp1 GTPase inhibitor, mdivi-1, (IC50 for mitochondrial fragmentation are 0.09, 0.06, and 10 μM, respectively). Both Drpitors reduced proliferation and induced apoptosis in cancer cells. Drpitor1a suppressed lung cancer tumor growth in a mouse xenograft model. Drpitor1a also inhibited mitochondrial ROS production, prevented mitochondrial fission, and improved right ventricular diastolic dysfunction during IR injury. In conclusion, Drpitors are useful tools for understanding mitochondrial dynamics and have therapeutic potential in treating cancer and cardiac IR injury.

Application of radical cross-dehydrogenative coupling (CDC) procedures to prepare a range of novel spirocyclic oxindoles and to a formal total synthesis of the vasopressin V2 receptor antagonist Satavaptan is reported. The key step involves a copper-mediated oxidative cyclisation of a simple linear anilide precursor to give the spirocyclic oxindole core. This synthetic approach was also used to prepare novel Satavaptan scaffolds and analogues.

Reported is the synthesis of carboxylic acids, symmetrical ketones, and unsymmetrical ketones with selectivity achieved by exploiting the differential reactivity of sodium methyl carbonate with Grignard and organolithium reagents.

A series of alkylated 2,3-dihydroxybiphenyls has been prepared on the gram scale by using an effective Directed ortho Metalation-Suzuki-Miyaura cross-coupling strategy. These compounds have been used to investigate the substrate specificity of the meta-cleavage dioxygenase BphC, a key enzyme in the microbial catabolism of biphenyl. Isolation and characterization of the meta-cleavage products will allow further study of related processes, including the catabolism of lignin-derived biphenyls.

The synthesis of bis-oxindoles via the copper(II)-mediated double cyclisation of linear bis-anilides is described. Cu(OAc)2·H2O was identified as an efficient and inexpensive catalyst for this process. In contrast to previous methods, which rely on the synthesis of the central core from existing oxindole building blocks, this new approach focusses on concurrent formation of both oxindole rings from a simple linear precursor, allowing the formation of bis-oxindoles containing a diverse range of cyclic and acyclic linkers using a single synthetic method.

Reported is the transition-metal-free synthesis of substituted dibenzoxazepinones using a convergent domino SNAr–Smiles rearrangement–SNAr process. Substrate-scope investigations demonstrated the critical importance of ring electronic effects on the efficiency of the process. In addition, the orthogonality of this approach with transition-metal-catalyzed procedures was established.

A copper(II)-catalysed approach to oxindoles, thio-oxindoles, 3,4-dihydro-1H-quinolin-2-ones, and 1,2,3,4-tetrahydroquinolines via formal C-H, Ar-H coupling is described. In a new variant, copper(II) 2-ethylhexanoate has been identified as an inexpensive and efficient catalyst for this transformation, which utilises atmospheric oxygen as the re-oxidant.

A double C-H, Ar-H coupling process for the conversion of bis-anilides into spirocyclic bis-oxindoles, enabling the concomitant formation of two all-carbon quaternary centers at oxindole 3-positions in a diastereoselective manner, is described. The optimum cyclization conditions utilize stoichiometric Cu(OAc)2·H2O/KOtBu in DMF at 110 °C and have been applied to prepare a range of structurally diverse bis-spirooxindoles in fair to good yields (28-77%); the method has also been extended to prepare bis-oxindoles linked by a functionalized acyclic carbon chain.

A new cyclisation procedure to prepare 4-carboxy-quinolin-2-ones via a one-pot Cu(II)-mediated radical cross-dehydrogenative coupling/sulfinic acid elimination of linear anilides is described. Extensions to more complex substrates are also reported as are applications in target synthesis allowing access to natural products isolated from Oryza sativa and HOFQ.

The reaction includes a formal C—N coupling of secondary benzamides assisted by an unexpected Smiles rearrangement.

The intramolecular hetero-Diels–Alder reaction of α,β-unsaturated oxime ethers as the diene with acetylenic dienophiles, readily prepared from salicylaldehyde derivatives, is described as a rapid and versatile route to [c]-annelated pyridines in modest to good yields.

The synthesis of bis-oxindoles via the copper(II)-mediated double cyclisation of linear bis-anilides is described. Cu(OAc)2·H2O was identified as an efficient and inexpensive catalyst for this process. In contrast to previous methods, which rely on the synthesis of the central core from existing oxindole building blocks, this new approach focusses on concurrent formation of both oxindole rings from a simple linear precursor, allowing the formation of bis-oxindoles containing a diverse range of cyclic and acyclic linkers using a single synthetic method.

Reported is the transition-metal-free synthesis of substituted dibenzoxazepinones using a convergent domino SNAr–Smiles rearrangement–SNAr process. Substrate-scope investigations demonstrated the critical importance of ring electronic effects on the efficiency of the process. In addition, the orthogonality of this approach with transition-metal-catalyzed procedures was established.

CEH is identified as inexpensive and efficient catalyst for all approaches to the title heterocycles including double cyclizations [cf.

The hetero-Diels–Alder reaction between 1-aza-3-siloxy-1,3-butadienes and electron deficient acetylenes is described. The reactivity of a range of α,β-unsaturated oximes and hydrazones is assessed in the synthesis of tri- and tetra-substituted pyridines bearing an oxygen functionality at C-3. Microwave irradiation has been employed to decrease the extended reaction times and increase the poor yields often associated with this reaction.

Simple, inexpensive catalysts formed in situ from tricyclohexylphosphine and palladium acetate or a phosphite-based palladacycle show unprecedented activity in the Suzuki coupling of deactivated, non-activated and activated aryl chloride substrates under microwave heating.

This study explored gender differences in how correctional officers react to severe occupational stress and addressed differences in coping processes and social support utilization. The subjects were 244 correctional officers (167 men and 77 women) employed in Kentucky medium security institutions for male offenders. The study employed a survey administered to the volunteering participants. The Ways of Coping Questionnaire was used to assess coping processes used to deal with a stressful work event, and the Maslach Burnout Inventory was used to assess severe occupational stress. Statistical analyses revealed that correctional officers experience high levels of occupational stress but did not indicate gender differences in emotional exhaustion or depersonalization. The results indicated that female officers more frequently than male officers processed stress by seeking social support, while male officers more frequently than female officers processed stress by “planful problem solving.” No differences were found in correctional officers’ relationships with oppositesex peers. The results suggested that male and female correctional officers follow traditional sex roles in coping with occupational stress, but they revealed no differences in how they are affected by occupational stress in terms of emotional exhaustion, depersonalization, and personal accomplishment.

The reaction includes a formal C—N coupling of secondary benzamides assisted by an unexpected Smiles rearrangement.

Systematic studies are presented demonstrating the complementarity of directed ortho metalation (DoM) and Ir-catalyzed strategies for the provision of borylated aromatics and their subsequent Suzuki-Miyaura coupling reactions. A new concept, the use of the TMS group, readily introduced by DoM, as a latent regiodirective moiety to overcome the otherwise problematic production of isomeric borylated product mixtures is presented. Additional electrophile-induced ipso-deborylation and DoM reactions of the Bpin products are described.

The intramolecular hetero-Diels–Alder reaction of α,β-unsaturated oxime ethers as the diene with acetylenic dienophiles, readily prepared from salicylaldehyde derivatives, is described as a rapid and versatile route to [c]-annelated pyridines in modest to good yields.

The naturally occurring 1,4-benzoquinones 2-methoxy-6-propyl-1,4-benzoquinone (1), 2-methoxy-6-pentyl-1,4-benzoquinone (primin 2), 2-methoxy-6-pentadecyl-1,4-benzoquinone (3), 2-methoxy-6-heptadecyl-1,4-benzoquinone (dihydroirisquinone, pallasone B; 4) were synthesized by a simple protocol involving microwave accelerated Claisen rearrangement of allyl ethers 10, followed by hydrogenation of the side chain alkene, and oxidation to the quinone. The Claisen-based methodology was extended to the first synthesis of the marine benzoquinones verapliquinones A and B (5 and 6), and panicein A (7). Isoarnebifuranone (9) was also synthesized by a similar strategy.

The synthesis of acridanes and related compounds through a Cu‐catalysed radical cross‐dehydrogenative coupling of simple 2‐[2‐(arylamino)aryl]malonates is reported. This method can be further streamlined to a one‐pot protocol involving the in situ fomation of the 2‐[2‐(arylamino)aryl]malonate by α‐arylation of diethyl malonate with 2‐bromodiarylamines under Pd catalysis, followed by Cu‐catalysed cyclisation.