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We synthesized cinnamoyl amide type compounds 1 with axial chirality. We demonstrated the use of (–)-1 for chiral ligands in Pd-catalyzed asymmetric allylic substitution reactions of allylic esters with indoles (up to 97% ee).

Asymmetric synthesis was performed by combining the photochemical reaction of an achiral substrate followed by crystallization-induced deracemization. The results indicated that a fused indoline produced by photochemical intramolecular δ-hydrogen abstraction and cyclization of N-(5-chloro-2-methylphenyl)phthalimide crystallized as a racemic conglomerate. Since this substrate has an aminal skeleton, racemization involving a ring-opening and ring-closing equilibrium process occurred under suitable conditions. Efficient racemization was observed in acetone containing a catalytic base, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). Crystallization-induced dynamic deracemization by Viedma ripening from racemic indoline was performed with an excellent enantioselectivity of 99 % ee. Furthermore, one-pot asymmetric synthesis of the indoline was achieved by the photochemical reaction of achiral phthalimide followed by continuous attrition-enhanced deracemization converging to 99 % ee of enantiomeric crystals. This is the first example of asymmetric expression and amplification by photochemical hydrogen abstraction and crystallization-induced dynamic deracemization.

We have synthesized a cyan fluorescent boron complex based on a tridentate imidazo[1,5-a]pyridine ligand. The boron complex was found to have potential applications as not only a chiroptical material but also a heavy-atom-free mitochondria-targeted photosensitizer for cancer treatment.

The highly enantioselective synthesis of p-anisoin was achieved via the benzoin condensation of a prochiral p-anisaldehyde using achiral NHC catalysts such as vitamin B1. In this reaction, p-anisoi...

Thermodynamic data for radium for radioactive waste management have been predicted using an electrostatic model and correlation with the ionic radii of the alkaline earth metals. Estimation of the standard Gibbs free energy of formation and standard molar entropy of aqueous radium species and compounds has been based on such approaches as extrapolation of the thermodynamic properties of strontium and barium, and use of a model of ion pair formation. The predicted thermodynamic data for radium have been compared with previously reported values.

We synthesized cinnamoyl amide type chiral P,olefin ligand (S)-4. We successfully obtained separable diastereomers of 4d and demonstrated Pd-catalyzed asymmetric allylic substitution reactions of indoles using (S,aS)-4d as a chiral ligand with high enantioselectivities (up to 98% ee).

Umpolung reactions of imines, especially the asymmetric reactions, have been extensively studied as they provide access to important chiral amines in an efficient manner. The reactions studied range from simple Michael reactions to several kinds of other reactions such as the aza-benzoin reaction, aza-Stetter reaction, addition with MBH carbonate, and Ir-catalysed allylation. Herein, we report the first umpolung alkylation reaction of α-iminoesters with alkyl halides mediated by iminophosphorane as an organic superbase. The desired products were obtained in up to 82% yield with almost perfect regioselectivities. The key to the regioselectivity of this reaction was the use of 4-trifluoromethyl benzyl imines as a substrate. The products were successfully derivatised into the more functionalised molecules in good yields.

Bromonium salts have been typically but infrequently used in various reactions as good leaving groups or as aryl or vinyl transfer reagents owing to their extremely high nucleofugality. Herein, we report the synthesis of novel, stable bromonium salts and their first catalytic application to the Michael reaction, with excellent product yield (up to 96%).

Seven racemic 5,7-dimethoxyflavanones afforded conglomerate crystals upon recrystallization from a solvent. Three methodologies were investigated to achieve asymmetric transformation based on dynamic crystallization of the chiral conglomerate system. The first was chiral symmetry breaking of racemic flavanones by attrition-enhanced deracemization. Continuous suspension of racemic flavanones in a small amount of propanol in the presence of a base (1,8-diazabicyclo[5.4.0]­undec-7-ene (DBU)) and glass beads promoted chiral symmetry breaking and converted the flavanones to crystals of (+)- or (−)-enantiomers with 78 to 99% ee. The second method involved cyclization of the intermediate aldol product to give optically active flavanone with 90% ee involving a reversible oxa-Michael addition reaction with attrition-enhanced deracemization. The third was a reaction starting from prochiral 2-hydroxy-4,6-dimethoxyacetophenone and 2-naphthaldehyde under basic conditions, which gave the corresponding flavanone in 89% ee.

Chiral symmetry breaking of thiohydantoins by attrition-enhanced deracemization was performed. It was found that three thiohydantoins afforded conglomerate crystals, and their absolute structures w...

We developed a chiral symmetry breaking method for monoacylated meso diols. The X-ray crystal structure analysis of monoacylated 1,4-anhydroerythritols, meso cyclic diols with a cis configuration, revealed that the O-(p-anisoyl) derivative crystallized as a racemic conglomerate of the P2

Atroposelective resolution for axially chiral nicotinamides was achieved by dynamic chiral salt formation with L-DBTA using six types of nicotinamides that could not be optically resolved by the preferential crystallization method. Kinetic studies of their racemization indicated that the chiral conformation was retained for a significant period of time. Two methods of crystallization-induced asymmetric transformation were examined by dynamic diastereomeric salt formation: solvent evaporation from a supersaturated solution, and attrition-enhanced asymmetric transformation. The attrition method was more effective for asymmetric amplification of diastereomeric salts of axially chiral materials. Attrition of equimolar amount of the nicotinamide salts with L-DBTA converged to one diastereomer salts, and the corresponding enantiomers in 87-99 % ee were obtained after the chiral acid was removed. Changing the ratio of two of the nicotinamides with L-DBTA to 1 : 2 inverted the axial chirality.

Longer cumulenes have come to draw considerable attention due to their unique properties and reactivities, leading to various hydrocarbons. In this manuscript, we describe the reaction of tetrakis(p-methoxyphenyl)[5]cumulene with iodine to afford poly-functionalized fulvenes via unexpected migration of a terminal aryl ring under ambient conditions. The obtained iodinated fulvenes were utilized in Suzuki-Miyaura cross-coupling reactions affording penta- and fully-arylated fulvenes successfully.

We have synthesized and characterized an acceptor-π-donor-π-acceptor type pyridinium salt. The salt exhibited yellow emission with large Stokes shift in solution and was successfully excited by NIR...

We have synthesized a series of quaternized imidazo[1,2-a]pyridines in three steps from commercially available reagents. These compounds exhibit blue fluorescence emission at around 425 nm with good quantum yields. In addition, one specific compound was found to work as not only a two- and three-photon excitable mitochondria imaging agent, but also a therapeutic agent upon continuous irradiation conditions.

Highlights • We presented a patient with gastric tube cancer who successfully underwent subtotal gastrectomy with intraoperative ICG fluorescence. • ICG fluorescence is useful for evaluating the flow of the gastric tube and helping to determine the operating method., Introduction Currently, the frequency of evaluating the flow of a reconstructed gastric tube using indocyanine green (ICG) fluorescence has been increasing. However, it has been difficult to decide on the operation method for patients with gastric tube cancer (GTC). We herein report a case in which ICG was effective in a patient with resection of GTC. Presentation of case An 83-year-old man underwent subtotal esophagectomy with gastric tube reconstruction via the retrosternal route for esophageal cancer and right hemicolectomy for ascending colon cancer 16 years earlier. Postoperatively, the proximal part of the gastric tube had poor blood flow. Therefore, the patient underwent proximal-side resection of the gastric tube. Thereafter, free jejunal graft reconstruction was performed. The patient had not developed recurrence at that point. Recently, the patient visited the hospital complaining of nausea and chest discomfort. Upper gastrointestinal endoscopy revealed a type 0-IIa + IIc lesion located around the pylorus. A biopsy showed adenocarcinoma. Based on these findings, the patient was diagnosed with gastric tube cancer (cT1bN0M0StageI). The invasion depth of the cancer was predicted to be widespread submucosal invasion. Therefore, the patient underwent surgery. Intraoperatively, we evaluated the flow of the gastric tube after clamping the right gastroepiploic artery using ICG fluorescence. As a result, the flow of the gastric tube was deemed insufficient. Consequently, subtotal gastrectomy was performed with preservation of the right gastroepiploic artery via Roux-en-Y reconstruction. Discussion ICG fluorescence is useful for evaluating the flow of the gastric tube helping to decide the operating method. Conclusion We herein report a case of subtotal gastrectomy for GTC using intraoperative ICG fluorescence.

The asymmetric synthesis of an aspartic acid derivative, N-succinopyridine, from prochiral starting materials involving dynamic enantioselective crystallization was accomplished without using any external chiral source. The aza-Michael addition reaction of prochiral maleic acid and pyridine afforded racemic conglomerate N-succinopyridine in water. Continuous stirring of the suspension of the reaction mixture with acetic acid promoted gradual deracemization to afford a crystal with an excellent optical purity of 99 % in 71 % yield.

A new class of flavonoids bearing cyclic polyethers involving a phenyl ring was conveniently provided by the intramolecular photochemical dimerization of 2-chromonecarboxylic esters. Irradiation of 2-chromonecarboxylate with a polyether tethered at both ends promoted intramolecular [2 + 2] cyclobutane formation leading to 14- to 27-membered cyclic polyethers. The efficiency depended on the substituted position of the phenyl ring, with ortho- and meta-substituted derivatives giving cycloadducts in good chemical yields and quantum efficiencies, whereas the para-derivatives were inert toward photolysis. X-ray crystallographic analysis revealed that the stereochemistry of the macrocyclic cycloadducts exhibited C2-symmetry.

Novel optically active hypervalent iodine(V) reagents with planar chiral crown ether backbones were synthesized using the intramolecular Huisgen reaction as a key step and l -methyl lactate as the source of chirality. The relative configurations of these reagents and stabilities of planar chiralities were determined by DFT calculations. These planar chiral reagents were applied to the hydroxylative dearomatization/[4 + 2]-dimerization reactions of phenols to afford bisthymol and biscarvacrol, a natural product, with moderate enantioselectivities.

The efficient chemo- and regioselective catalytic asymmetric syntheses of enamides, which are important core structures of bioactive natural products, have been achieved through the first umpolung organocascade reaction of α-imino amides. A variety of enamides have been synthesized enantioselectively in high yields with up to 99% ee. Notably, both enantiomers of the products can be selectively prepared by the simple pretreatment of the substrate. Mechanistic studies reveal that E/ Z-geometry information from the substrate is transferred to the product. The present method can be applied to a wide range of α-imino amides, irrespective of the electronic nature of the substituents.

We have synthesized a cyan fluorescent boron complex based on a tridentate imidazo[1,5

Chiral amino thioesters are important scaffolds owing to their widespread use in organic synthesis and biosynthesis. Despite their usefulness, their asymmetric synthesis, especially the catalytic asymmetric synthesis of α-chiral tetrasubstituted α-aminothioesters, is limited, with only one example reported so far. Herein, we report the first phase-transfer catalysed asymmetric synthesis of α-chiral tetrasubstituted α-aminothioesters to afford the corresponding products in up to 81% ee.

The study of chirogenesis of organic molecules is important to elucidate the origin of the homochirality of biomolecules on Earth. Here, we have accomplished chiral symmetry breaking from a racemate using optical vortices with orbital angular momentum and a helical wavefront. We propose a new methodology of asymmetric transformation by the combination of enantioselective crystal nucleation by irradiation with optical vortices and crystallization-induced dynamic optical resolution of conglomerate crystals. Chiral green vortices generated using a spiral phase plate (SPP) with a 532 nm CW-laser were used to irradiate a supersaturated solution of a racemic isoindolinone, leading to crystal nucleation. The handedness of the crystals were controlled by the winding direction of the chiral optical vortices. The molecular chirality of the isoindolinone was then amplified by dynamic crystallization.

Bromonium salts have been typically but infrequently used in various reactions as good leaving groups or as aryl or vinyl transfer reagents owing to their extremely high nucleofugality. Herein, we report the synthesis of novel, stable bromonium salts and their first catalytic application to the Michael reaction, with excellent product yield (up to 96%).

We present a 46-year-old female patient who underwent resection of a retroperitoneal tumor, which was found by medical check-up. The tumor which was elastic hard and had good mobility displaced the duodenum to her abdominal wall. Since her right ovarian vein adhered to the tumor, we removed the tumor with the ligated vein. Pathological findings showed the tumor consisted of spindle-shaped cells with pleomorphic nucleus and it presented the fascicular growth pattern. Additional immunostaining showed positive for HHF35, h-caldesmon. Because the leiomyosarcoma connected with the smooth muscle of the right ovarian vein, we considered the vascular smooth muscle was the origin of the tumor. It is 2 years after the operation, there has been no local recurrence or metastasis.

An 80-year-old woman who visited our hospital with chief complaints of decreased appetite and diarrhea. Lower gastrointestinal endoscopy showed a type 2 tumor in the rectal Ra, and biopsy revealed a well-differentiated adenocarcinoma. The patient had locally advanced rectal cancer with widespread contact with the sacrum, and preoperative radiochemotherapy (S-1 100 mg/day plus radiotherapy 50 Gy/25 Fr)was performed. After the treatment was completed, the tumor was remarkably reduced, but the surgery was strongly rejected, and therefore chemotherapy became the policy. XELOX plus bevacizumab therapy was started, but in the second course was performed, obstructive symptoms appeared, so a semi-urgent lower anterior resection and ileostomy were performed. Postoperative pathological findings showed only a small amount of tumor cells in the mucosa, suggesting that preoperative treatment was effective.

We have synthesized a series of quaternized imidazo[1,2-a]pyridines in three steps from commercially available reagents. These compounds exhibit blue fluorescence emission at around 425 nm with good quantum yields. In addition, one specific compound was found to work as not only a two- and three-photon excitable mitochondria imaging agent, but also a therapeutic agent upon continuous irradiation conditions.

A 58-year-old man with unresectable sigmoid colon cancer and multiple liver metastases(H2, more than 30)received chemotherapy for 2 years. Subsequently, the patient was diagnosed with stenosis of the primary lesion and 5 bilobar, metastatic tumors. Simultaneous resection was unsuitable because of the performance status and comorbidities of the patient. The first surgery consisted of laparoscopic-assisted sigmoidectomy, laparoscopic microwave coagulation therapy(MCT), and percutaneous radiofrequency ablation(RFA). Percutaneous RFA was additionally performed after 2 months. Since 2 liver metastases(S3 and S8)were inadequately treated, 3 courses of P-mab plus FOLFIRI were administered. Finally, laparoscopic- assisted RFA was performed. Subsequently, serum CEA reduced from 288.3 ng/mL to the normal level. We used fusion imaging US, sonazoid US, laparoscopic convex probe, and ICG fluorescence imaging for ablation therapy. Chemotherapy and ablation therapy using various approaches can control unresectable multiple liver metastases and prolong survival by more than 3 years.

We synthesized N-trans-cinnamyl-N-cyclohexylaniline type aminophosphine 2 and a series of N-2-adamantyl-N-trans-cinnamylaniline type aminophosphines 3. Although aminophosphine 2 failed to find the existence of axial chirality, aminophosphines 3, which exist in the axial chirality in a C(aryl)-N(amine) bond by chiral HPLC analysis as 1-adamantyl type chiral ligands 1. Enantiomeric isomers of 3b, 3c, and 3d were obtained in an enantiomerically pure form. We also identified the palladium-catalyzed asymmetric allylic substitution of 1,3-diphenyl-2-propenyl acetate with indoles using aminophosphines 3b-d as effective chiral ligands in high enantioselectivities (up to 96% ee).