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Abstract In the treatment of chronic myeloid leukemia (CML), resistance to BCR‐ABL inhibitors makes it difficult to continue treatment and is directly related to life expectancy. Therefore, asciminib was introduced to the market as a useful drug for overcoming drug resistance. While combining molecular targeted drugs is useful to avoid drug resistance, the new BCR‐ABL inhibitor asciminib and conventional BCR‐ABL inhibitors should be used as monotherapy in principle. Therefore, we investigated the synergistic effect and mechanism of the combination of asciminib and imatinib. We generated imatinib‐resistant cells using the human CML cell line K562, examined the effects of imatinib and asciminib exposure on cell survival using the WST‐8 assay, and comprehensively analyzed genetic variation related to drug resistance using RNA‐seq and real‐time PCR. A synergistic effect was observed when imatinib and asciminib were combined with or without imatinib resistance. Three genes, GRRP1, ESPN, and NOXA1, were extracted as the sites of action of asciminib. Asciminib in combination with BCR‐ABL inhibitors may improve the therapeutic efficacy of conventional BCR‐ABL inhibitors and prevent the development of resistance. Its dosage may be effective even at minimal doses that do not cause side effects. Further verification of this mechanism of action is needed. Additionally, cross‐resistance between BCR‐ABL inhibitors and asciminib may occur, which needs to be clarified through further validation as soon as possible.

Commercially available and air- and moisture-stable rhodium complex [Rh(OH)(cod)]2 (2) was utilized in the synthesis of [RhX(cod)(NHC)] (3). The presence of an OH group in complex 2 serves as an internal base, facilitating the deprotonation of the C–H bond of the azolium ring in the hydroxyamide-substituted benzimidazolium salt 1. This reaction between 1 and 2 proceeded in THF at room temperature without temperature control, affording the desired NHC/Rh complex 3 in excellent yield. The characterization of complex 3 was accomplished through NMR and HRMS analyses, revealing its existence as a diastereomeric mixture of two NHC/Rh complexes. Furthermore, its catalytic performance was briefly evaluated in the reaction between 2-naphthaldehyde (5) and phenylboronic acid (6).

Previously, we demonstrated the synthesis of a well-defined hydroxyalkyl-functionalized N-heterocyclic carbene (NHC)/Ru(II) complex through the transmetalation reaction between [RuCl2(p-cymene)]2 and the corresponding NHC/Ag(I) complex derived from a chiral benzimidazolium salt using the Ag2O method. In this study, we successfully synthesized [RhX(cod)(NHC)] complexes through a one-pot deprotonation route. The hydroxyalkyl-substituted benzimidazolium salt reacted with [Rh(OH)(cod)]2 in THF at room temperature, affording the corresponding monodentate NHC/Rh(I) complex in nearly quantitative yield. The rhodium complex was characterized using NMR, HRMS measurement, and elemental analysis.

BackgroundAmyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder, with its currently approved drugs, including riluzole and edaravone, showing limited therapeutic effects. Therefore, safe and effective drugs are urgently necessary. EPI-589 is an orally available, small-molecule, novel redox-active agent characterized by highly potent protective effects against oxidative stress with high blood-brain barrier permeability. Given the apparent oxidative stress and mitochondrial dysfunction involvement in the pathogenesis of ALS, EPI-589 may hold promise as a therapeutic agent. ObjectiveThis protocol aims to describe the design and rationale for the EPI-589 Early Phase 2 Investigator-Initiated Clinical Trial for ALS (EPIC-ALS). MethodsEPIC-ALS is an explorative, open-labeled, single-arm trial that evaluates the safety and tolerability of EPI-589 in patients with ALS. This trial consists of 12-week run-in, 24-week treatment, and 4-week follow-up periods. Patients will receive 500 mg of EPI-589 3 times daily over the 24-week treatment period. Clinical assessments include the mean monthly change of Amyotrophic Lateral Sclerosis Functional Rating Scale–Revised total score. The biomarkers are selected to analyze the effect on oxidative stress and neuronal damage. The plasma biomarkers are 8-hydroxy-2′-deoxyguanosine (8-OHdG), 3-nitrotyrosine (3-NT), neurofilament light chain (NfL), phosphorylated neurofilament heavy chain (pNfH), homocysteine, and creatinine. The cerebrospinal fluid biomarkers are 8-OHdG, 3-NT, NfL, pNfH, and ornithine. The magnetic resonance biomarkers are fractional anisotropy in the corticospinal tract and N-acetylaspartate in the primary motor area. ResultsThis trial began data collection in September 2021 and is expected to be completed in October 2023. ConclusionsThis study can provide useful data to understand the characteristics of EPI-589. Trial RegistrationJapan Primary Registries Network jRCT2061210031; tinyurl.com/2p84emu6 International Registered Report Identifier (IRRID)DERR1-10.2196/42032

Asymmetric silane reduction of ketones catalyzed by a system comprising a chiral azolium salt 1 and [Ir(cod)2]BF4 (2) in the presence of a base in methanol was achieved at room temperature within 2 h. Implementing a “pre-mixing” experimental procedure improved the efficiency of the catalytic reaction. Specifically, after treating a mixture of 1 and 2 with (EtO)2MeSiH (3a) in THF, the ketone substrate was allowed to react in the presence of K2CO3 in methanol at room temperature to afford the corresponding optically active alcohol in high yield and enantioselectivity. The reaction parameters were fully evaluated. The presence of 3a in the pre-mixing step and that of a base in the reduction step were found to be essential for success. The developed method was applied to the stereoselective reduction of β-keto esters. Additionally, an iridium species derived from the reaction of 1 with [IrCl(cod)]2 and AgBF4 was investigated.

Hydroxyamide-functionalized azolium salt (NHC•HI 4) was evaluated for dual enantioselective control in a Cu-catalyzed asymmetric conjugate addition (ACA) reaction. This investigation was based on our previously reported ACA reaction catalyzed using CuOTf combined with NHC•AgI complex 1. It was revealed that the stereocontrol of the catalytic ACA reaction depended on the order of the addition of the substrates. Additionally, the chiral NHC ligand precursors, substrates, the relationship between the catalyst ee (eecat) and product ee (eepro), and halogen counter anion were completely evaluated. These results suggested that the catalytic performance of the CuOTf/4 system was comparable with that of the CuOTf/1 system. Furthermore, to gain knowledge of the Cu species generated using CuOTf and NHC ligand precursor, the reaction of CuOTf with 1 was investigated. Although obtaining the corresponding NHC•CuX species failed, the corresponding NHC•AuCl complex 11 could be synthesized by allowing 1 to react with AuCl•SMe2.

A 60-year-old man was admitted to our hospital with non-small cell lung cancer (NSCLC). Imaging and pathological studies revealed NSCLC, not otherwise specified (NOS), at clinical stage T3N1M0 stage IIIA. We started radiotherapy alone because of obstructive pneumonia and end-stage renal disease, but the tumors progressed rapidly and resulted in death due to air obstruction by pharyngeal metastasis. The cancer was diagnosed as pleomorphic carcinoma in an autopsy. Viable lung tumor cells, which were resistant to radiotherapy, and the pharyngeal metastasis had mesenchymal phenotypes and expressed ZEB1 but not SNAI1. These observations indicated that ZEB1-associated epithelial-mesenchymal transition has malignant features including resistance to radiotherapy and aggressive metastatic potential. ZEB1-associated EMT may be an important mechanism to understand the pathophysiology of pleomorphic carcinoma. Keywords: Pulmonary pleomorphic carcinoma, Epithelial-mesenchymal transition (EMT), ZEB1

Bis(NHC) ligand precursors, L1, based on trans-1,2-diaminocyclohexane were designed and synthesized. To introduce chirality at the hydroxyamide side arm on the NHC of L1, a chiral β-amino alcohol, such as enantiopure leucinol, was used. Cu-catalyzed asymmetric conjugate addition reactions of cyclic and acyclic enones with Et2Zn were selected to evaluate the performance of L1 as a chiral ligand. For the reaction of cyclic enone, a combination of [bis(trimethylsilyl)acetylene]-(hexafluoroacetylacetonato)copper(I) (Cu(hfacac)(btmsa)) with a (±)-trans-1,2-cyclohexanediamine-based bis(NHC) ligand precursor, (rac; S,S)-L1, which was prepared from (S)-leucinol, was the most effective. Thus, treating 2-cyclohexen-1-one (3) with Et2Zn in the presence of catalytic amounts of Cu(hfacac)(btmsa) and (rac; S,S)-L1 afforded (R)-3-ethylcyclohexanone ((R)-4) with 97% ee. Similarly, use of (rac; R,R)-L1, which was prepared from (R)-leucinol, produced (S)-4 with 97% ee. Conversely, for the asymmetric 1,4-addition reaction of the acyclic enone, optically pure (−)-trans-1,2-cyclohexanediamine-based bis(NHC) ligand precursor, (R,R; S,S)-L1, worked efficiently. For example, 3-nonen-2-one (5) was reacted with Et2Zn using the CuOAc/(R,R; S,S)-L1 catalytic system to afford (R)-4-ethylnonan-2-one ((R)-6) with 90% ee. Furthermore, initially changing the counterion of the Cu precatalyst between an OAc and a ClO4 ligand on the metal reversed the facial selectivity of the approach of the substrates. Thus, the conjugate addition reaction of 5 with Et2Zn using the Cu(ClO4)2/(R,R; S,S)-L1 catalytic system, afforded (S)-6 with 75% ee.

Background: Enforcement of the 2018 Clinical Trials Act (CTA) in Japan resulted in strict and complicated regulations surrounding intervention studies. Few Japan-specific measures have been developed to promote intervention studies in Japan despite concerns about CTA's negative influence on such studies. Therefore, this study examined the changes in academic investigators' interest in conducting clinical studies before and after enforcement of the CTA to determine measures to promote specified clinical trials. Methods: We conducted a questionnaire survey with investigators belonging to the Institute of Biomedical Sciences, Tokushima University Graduate School, before and after enforcement of the CTA. Results: Investigators had lesser interest in intervention studies in the post-questionnaire survey (post) group than in the pre-questionnaire survey (pre) group. Their desire for "project management" was significantly higher in the post-group than in the pre-group. Their desire for "support for preparing documents when conducting specified clinical trials" was significantly higher in the group interested in conducting specified clinical trials than that in the not-interested group. Conclusion: We revealed that investigators were highly interested in "project management" and "support for preparing documents when conducting specified clinical trials" after enforcement of the CTA. Measures for these desires may promote specified clinical trials. [ABSTRACT FROM AUTHOR]

The lifetimes and spin-lattice relaxation time of photo-excited triplet electron of pentacene doped in p-terphenyl at room temperature have been investigated. Values of spin-lattice relaxation time previously reported in ESR studies are inconsistent with each other. In this paper, we determined these time constants based on proton signals enhanced by dynamic nuclear polarization using the electrons (Triplet-DNP). The combined analysis of dependences of proton signal intensities on the delay time of polarization transfer and laser pulse structure allows us to disentangle contributions of the lifetimes and spin-lattice relaxation time. The lifetimes of triplet sublevels with ms = 0 and ±1 were determined to be 22.3 and 88 µs, respectively. The spin-lattice relaxation time was found to be longer than 300 µs, hence the time evolution of the electron population in the triplet state is governed by the lifetimes. It was also found that the proton signal enhancement is limited at a high repetition rate by the partial cancellation of the electron spin polarization by the remaining population produced by the preceding laser pulses. [ABSTRACT FROM AUTHOR]

A hydroxyamide-functionalized azolium salt as the precursor of a (±)-trans-1,2-cyclohexanediamine-based bis(NHC) ligand was designed and synthesized from readily accessible L-leucinol. The combination of a Cu salt with this chiral ligand precursor promoted the asymmetric conjugate addition of Et2Zn to 2-cyclohexen- 1-one at room temperature without the need for temperature control to afford the corresponding 1,4-adduct with up to 95% ee. [ABSTRACT FROM AUTHOR]

Oxidative arylation of ethylene with benzene was examined by using a Pd(OAc)2/heteropoly acid/O2 system under mild conditions. The reaction of benzene with ethylene in the presence of catalytic amounts of Pd(OAc)2 combined with H4PMo11VO40·15H2O (or H3PMo12O40·30H2O), AcONa, and dibenzoylmethane under air at 90–120 °C produced oxidative coupling products, styrene and stilbene, in fair yields (up to 167 total turnovers). From the examination of the catalyst performance of Pd(OAc)2 combined with various heteropoly acids, it was found that the employment of heteropoly acids including molybdenum ion in their structure is very important to obtain high turnover numbers of Pd. [ABSTRACT FROM AUTHOR]