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In a screen of compounds to selectively suppress the growth of cancer spheroids, which contained mutant (mt) KRAS, NPD10621 was discovered and associated derivatives were investigated.Spheroid areas from HCT116-derived HKe3 spheroids expressing wild type (wt) KRAS (HKe3-wtKRAS) and mtKRAS (HKe3-mtKRAS) were treated with 12 NPD10621 derivatives and measured in three-dimensional floating (3DF) cultures. Several cancers were treated with NPD1018 (pyra-metho-carnil: PMC) in 3DF cultures. In a nude mouse assay, 50% cell growth inhibition (GIFrom these 12 derivatives, PMC was the most effective inhibitor of HKe3-mtKRAS spheroid growth with the least toxicity. Furthermore, PMC-mediated growth suppression was observed in all tested cancer cell lines, independent of tissue context, driver gene mutations, and drug resistance, suggesting that the PMC target(s) was crucial for cancer growth in a context-independent manner. The GIPMC is a low-toxicity compound that inhibits the growth of different tumor cell types.

Postoperative complications are associated with increased recurrence in colorectal cancer (CRC). We investigated the impact of infectious complications on the recurrence of CRC and overall survival after curative surgery in a single study group.In total, 1,668 patients who underwent radical resection for CRC in Yokohama City University, Yokohama Minami Kyosai Hospital, and Kanagawa Cancer Center between 2011 and 2019 were reviewed. Patients were classified into those with infectious complications (IC group) and those without infectious complications (Non-IC group). The risk factors for recurrence-free survival (RFS) and overall survival (OS) were analyzed.Postoperative complications were found in 560 of the 1,668 patients (33.5%), and IC, which occurred in 312 patients (18.7%), included pneumonia, anastomotic leakage, and intraperitoneal abscess. The 5-year OS rates in the Non-IC and IC groups were 95.5% and 90.4%, respectively, while the 5-year RFS rates were 74.4% and 68.1%, respectively. The multivariate analysis demonstrated that postoperative IC were significant independent risk factors for OS and RFS.The presence of postoperative IC after CRC resection is associated with decreased long-term survival. The surgical procedure, surgical strategy, and perioperative care should be carefully planned in order to avoid causing IC.

Postoperative pancreatic fistula (POPF) is one of the major critical complications after pancreatic resection. Recently, postoperative acute pancreatitis (POAP), a new concept for a pancreatic-specific complication following pancreatic resection, has been advocated, and its association with POPF has been reported. The present study examined the clinical features of POAP and identified the associations of POAP with POPF and other postoperative morbidities in pancreatic ductal adenocarcinoma (PDAC) patients undergoing pancreatic resection.A total of 312 consecutive patients who underwent pancreatic resection for PDAC at our institution from 2013 to 2019 were enrolled in this study. POAP was defined as an elevated serum amylase level above the upper limit normal on postoperative day (POD) 0 or 1, based on Connor's definition. The severity of POPF was assessed by the International Study Group on Pancreatic Surgery definition.A total of 184 patients (58.9%) had POAP. POAP occurred in 58.5% of subtotal stomach-preserving pancreatoduodenectomy patients and 60% of distal pancreatectomy combined with splenectomy patients. The presence of POAP was significantly associated with the development of clinically relevant POPF, higher rates of severe morbidity, and a prolonged hospital stay after pancreatic resection. A multivariate analysis showed that the presence of POAP and elevated C-reactive protein levels on POD 3 were independent predictors of clinically relevant POPF after subtotal stomach-preserving pancreatoduodenectomy.POAP is associated with the development of POPF, higher rates of severe morbidity, and a prolonged hospital stay after pancreatic resection and is an independent risk factor for clinically relevant POPF after pancreatoduodenectomy. POAP represents an important indicator for planning treatment strategies to prevent serious complications, including POPF.

We report a direct catalytic enantioselective hydrophosphonylation of N-unsubstituted ketimines that affords N-unprotected α-tetrasubstituted α-aminophosphonates without protection/deprotection steps. The reaction is suitable for N-unsubstituted isatin-derived ketimines and N-unsubstituted trifluoromethyl ketimines, affording products in high yields with excellent enantioselectivity. Applications of the reaction and a proposed transition state model are also described.

Catalytic addition reactions to N-unsubstituted (N-unprotected) imines can provide a more straightforward synthesis of amines. This direct process eliminates the unnecessary protecting-group manipu...

We developed a catalytic aerobic method to synthesize α,α-disubstituted α-amino acids through cross-dehydrogenative coupling of azlactones. Combining an iron catalyst with a bisoxazolidine ligand resulted in high catalytic performance, and cross-coupling with an indole proceeded smoothly under aerobic conditions. A wide variety of α-aryl and aliphatic amino acid derived azlactones were applied to the present catalysis. In addition, a quaternary carbon could be constructed using oxindole and benzofuranone under aerobic conditions.

Benzophenone imine and its derivatives are useful ammonia equivalents for synthesizing primary amines, readily achieving the selective formation of primary amines and obtaining easily deprotectable...

Unnatural α-amino acids are invaluable building blocks in synthetic organic chemistry and could upgrade the function of peptides. We developed a new mode for catalytic activation of amino acid Schiff bases, serving as a platform for highly congested unnatural α-amino acid synthesis. The redox active copper catalyst enabled efficient cross-coupling to construct contiguous tetrasubstituted carbon centers. The broad functional group compatibility highlights the mildness of the present catalysis. Notably, we achieved successive β-functionalization and oxidation of amino acid Schiff bases to afford dehydroalanine derivatives bearing tetrasubstituted carbon. A three-component cross-coupling reaction of an amino acid Schiff base, alkyl bromides, and styrene derivatives demonstrated the high utility of the present method. The diastereoselective reaction was also achieved using menthol derivatives as a chiral auxiliary, delivering enantiomerically enriched α-amino acid bearing α,β-continuous tetrasubstituted carbon. The synthesized highly congested unnatural α-amino acid could be derivatized and incorporated into peptide synthesis.

N-Unprotected ketimines are useful substrates and intermediates for synthesizing valuable nitrogen-containing compounds, but their potential applicability is limited by the available synthetic methods. To address this issue, we report a scandium(III) triflate catalyzed direct synthesis of N-unprotected ketimines. Using commercially available reagents and Lewis acid catalysts, ketones were directly transformed into the corresponding N-unprotected ketimines in high yields with broad functional group tolerance, even in multigram scales. The reactions were readily applicable for one-pot synthesis of important compounds such as a glycine Schiff base without isolation of N-unprotected ketimine intermediates. Preliminary mechanistic studies to clarify the reaction mechanism are also described.

A synthetic method for the synthesis of a highly congested α,β-dehydroamino acid through the β-C-H bond activation of an amino acid Schiff base is described. Abundant hydrocarbon feedstock could be used as an alkylating reagent to afford an α,β-dehydroamino acid bearing a quaternary carbon at the γ-position with an exclusively (

The full-energy beam injection system from SACLA to the SPring-8 storage ring has been developed. Low-emittance beam injection is required for the future upgrade of SPring-8 due to its small injection beam aperture. The electron beam injection from an X-ray free-electron laser linear accelerator not only satisfies the emittance requirement but also it confers a cost benefit compared to a conventional dedicated injector system. In SPring-8, the SACLA linear accelerator is now delivering X-ray free-electron laser photon beams and serving as a full-time injector of SPring-8 in parallel.

A study of ammonium salt-accelerated hydrazinolysis of unactivated amides is described. We first studied the reaction mechanism by kinetic experiments and DFT calculations and found that cooperation of the hydrazinium salt and hydrazine is important for promoting the cleavage of unactivated amides. Next, we applied the reaction to a microwave flow process, and the amine products were isolated on a multigram scale.

A catalytic enantioselective Strecker reaction of isatin-derived N-unsubstituted ketimines directly afforded the N-unprotected α-aminonitriles with a tetrasubstituted carbon stereocenter in up to 99% ee without requiring protection/deprotection steps. One-pot Strecker reactions from the parent carbonyl compounds were also realized with comparable yields and enantioselectivities. Direct transformations of the N-unprotected α-aminonitrile products streamlined the synthesis of unnatural amino acid derivatives and achieved the shortest one-pot stereoselective routes to a biologically active compound reported to date.

Background/aim Among compounds from natural products selectively suppressing the growth of cancer spheroids, which have mutant (mt) KRAS, NP910 was selected and its derivatives explored. Materials and methods The area of HKe3 spheroids expressing wild type (wt) KRAS (HKe3-wtKRAS) and mtKRAS (HKe3-mtKRAS) were measured in three-dimensional floating (3DF) cultures treated with 18 NP910 derivatives. The 50% cell growth inhibition (GI50) was determined by long-term 3DF (LT3DF) culture and nude mice assay. Results We selected NP882 (named STAR3) as the most effective inhibitor of growth of HKe3-mtKRAS spheroids with the least toxicity among NP910 derivatives. GI50s of STAR3 in LT3DF and nude mice assay were 6 μM and 30.75 mg/kg, respectively. However, growth suppression by STAR3 was observed in 50% of cell lines independent of KRAS mutation, suggesting that the target of STAR3 was not directly associated with KRAS mutation and KRAS-related signals. Conclusion STAR3 is a low-toxicity compound that inhibits growth of certain tumour cells.

Over the last few decades, the quest for environmentally benign chemical transformations has become an important topic in both industrial and academic research. An integrated synthesis that combines multiple reactions in a single operation in a one-pot or a flow system without isolating intermediates has recently drawn much attention as a replacement for conventional step-by-step synthesis. Because in the reaction integration process the reaction mixtures are directly used to the next reaction without purification and the generated co- and by-products may have negative effects on the next reaction, integrating highly atom-economical reactions is quite important. To this end, we developed several highly atom-economical direct catalytic reactions. In this review, we focused on the developments of synthesis and reactions of N-unprotected ketimines and their applications for time integration (one-pot sequential process through N-unprotected ketimine synthesis).

2-Acylimidazoles are widely used as post-transformable carboxylic acid equivalents in chemoselective and enantioselective reactions. Their transformations, however, require pretreatment with highly reactive, toxic methylating reagents to facilitate C-C bond cleavage. Here, we demonstrate that such pretreatment can be avoided and the C-C bond cleaved under neutral conditions without the use of additional reagents or catalysts. The scope of the reaction, including the use of products reported in the literature as substrates, and some mechanistic insights are described.

Lifestyle and germline factors determine specific gastric carcinogenesis of East Asians., Germline and environmental effects on the development of gastric cancers (GC) and their ethnic differences have been poorly understood. Here, we performed genomic-scale trans-ethnic analysis of 531 GCs (319 Asian and 212 non-Asians). There was one distinct GC subclass with clear alcohol-associated mutation signature and strong Asian specificity, almost all of which were attributable to alcohol intake behavior, smoking habit, and Asian-specific defective ALDH2 allele. Alcohol-related GCs have low mutation burden and characteristic immunological profiles. In addition, we found frequent (7.4%) germline CDH1 variants among Japanese GCs, most of which were attributed to a few recurrent single-nucleotide variants shared by Japanese and Koreans, suggesting the existence of common ancestral events among East Asians. Specifically, approximately one-fifth of diffuse-type GCs were attributable to the combination of alcohol intake and defective ALDH2 allele or to CDH1 variants. These results revealed uncharacterized impacts of germline variants and lifestyles in the high incidence areas.

We developed a chemoselective catalytic activation of carboxylic acid for a 1e- radical process. α-Oxidation of a variety of carboxylic acids, which preferentially undergo undesired decarboxylation under radical conditions, proceeded efficiently under the optimized conditions. Chemoselective enolization of carboxylic acid was also achieved even in the presence of more acidic carbonyls. Extensive mechanistic studies revealed that the cooperative actions of iron species and alkali metal ions derived from 4 A molecular sieves substantially facilitated the enolization. For the first time, catalytic enolization of unprotected carboxylic acid was achieved without external addition of stoichiometric amounts of Bronsted base. The formed redox-active heterobimetallic enediolate efficiently coupled with free radical TEMPO, providing synthetically useful α-hydroxy and keto acid derivatives.

Although BINOL-derived phosphoric acids are among the most widely used chiral Brønsted acid organocatalysts, their structures are mostly limited to 3,3'-disubstituted ones and simple 3-mono-substituted ones without any polar functionalities on the 3-substituent have not been used in highly enantioselective reactions. This work reports such 3-mono-substituted analogues as effective organocatalysts in direct highly enantioselective Friedel-Crafts-type alkylation of N-unprotected α-ketiminoester. The origin of the observed high enantioselectivity with the 3-mono-substituted catalyst is also discussed.

Enantioselective addition of boronic acids to N-unsubstituted isatin-derived ketimines was realized using rhodium(I)/chiral diene catalysts. The reactions can be performed in the presence of catalytic amounts of a base to give adducts in high yield with high enantioselectivity. Preliminary mechanistic information including a computational model to explain the observed enantioselectivity is also provided.

The first catalytic enantioselective decarboxylative Mannich-type reaction of N-unprotected ketimines is reported, directly providing N-unprotected 3-tetrasubstituted 3-aminooxindoles in high yield and ee without protection/deprotection steps. The utility of this reaction is demonstrated in the short step synthesis of (+)-AG-041R.

Chemoselective iron-catalyzed dehydrogenative cross-coupling using 2-acylimidazoles is described. The addition of a phosphine oxide ligand substantially facilitated the generation of tert-butoxy radicals from di-tert-butyl peroxide, allowing for efficient benzylic C–H bond cleavage under mild conditions. Extensive mechanistic studies revealed that the enolization of 2-acylimidazole proceeded through dual iron catalyst activation, followed by subsequent chemoselective cross-coupling with a benzyl radical over an undesired benzyl radical-derived homocoupling dimer that inevitably formed in earlier reported conditions. A variety of alkylarenes, aliphatic alkane, and functionalized 2-acylimidazoles were applicable, demonstrating the synthetic utility of the present catalysis. Contiguous all-carbon quaternary carbons were constructed through dehydrogenative cross-coupling. The catalytic chemoselective activation of 2-acylimidazole over bidentate coordinative and much more acidic malonate diester was particular...

Background/aim During screening for compounds that selectively suppress growth of human colorectal cancer (CRC) spheroids with mutant (mt) KRAS, the uridine analogue, 5-bromouridine (BrUrd) was identified and its derivatives were explored. Materials and methods DNA incorporation in two-dimensional (2D) and three-dimensional floating (3DF) cultures was examined with the uridine analogue, 5-ethynyl-2'-deoxyuridine (EdU). The area of HKe3 CRC spheroids expressing wild type (wt) KRAS (HKe3-wtKRAS) and mtKRAS (HKe3-mtKRAS) were measured in 3DF culture with 11 BrUrd derivatives. Results EdU was strongly incorporated into newly-synthesized DNA from HKe3-mtKRAS cells compared to HKe3-wtKRAS in 2D and 3DF culture. 3-Deaza-cytarabine, which has properties of BrUrd and cytidine, was the most effective inhibitor of HKe3-mtKRAS spheroids with the least toxicity to HKe3-wtKRAS. Growth suppression of 3-deaza-cytarabine was stronger than cytarabine in 2D culture, and toxicity was lower than gemcitabine in long-term 3DF culture. Conclusion 3-Deaza-cytarabine exhibits properties useful for the treatment of CRC patients with mtKRAS.

A synthetic route to trans-configured tetrahydrothiophenes (THTs) through Fe(OTf)3 -promoted [3+2] cycloaddition of donor-acceptor cyclopropanes with thionoesters was developed. The cycloaddition proceeded in high yield with high diastereoselectivity, affording transient α-alkoxy THTs. Not only aromatic and aliphatic thionoesters, but also thionolactone were applicable to the present iron catalysis. Further transformation of the S,O-ketal functionality of the product was achieved in a highly trans diastereoselective manner. Moreover, the utility of our methodology was clearly demonstrated by the synthesis of enantioenriched trans-configured THTs.

A benzylic substitution of 3-indolyl(hydroxyl)acetate derivatives with thiols proceeded specifically in the presence of amino, carboxy, and phosphate groups in weakly acidic aqueous solutions under nearly physiological condition, while no reaction occurred at pH over 7. Kinetic studies revealed that the reaction followed second-order kinetics (first-order in the reactant and first-order in thiol) in contrast with the SN 1 mechanism of common benzylic substitution of alcohols. The utility of the present method for functionalization of biomacromolecules was demonstrated using several model proteins, such as lysozyme, insulin, trypsin, and serum albumin. The catalytic bioactivity of lysozyme in lysis of Micrococcus lysodeikticus cells was completely retained after the modification.