Article
Chemistry, Organic
Valluru Krishna Reddy, Keizo Kan, Yasser Samir Abdel-Khalek Sokeirik, Keisuke Yoshida, Atsushi Hirata, Masahiro Yamanaka, Yoshihiro Ueda, Takeo Kawabata
Summary: The method for kinetic resolution of 2,2'-disubstituted 1,1'-binaphthyl-8,8'-diamines was developed through enantioselective acylation of the amino group with chiral pyrrolidinopyridine organocatalysts. The accelerative enantioselective acylation was proposed to be due to multiple hydrogen-bonding interactions and pi-pi interaction between the catalyst and the diamines.
Article
Chemistry, Organic
Martina Costanzo, Mauro Cortigiani, Malachi W. Gillick-Healy, Brian G. Kelly, Claudio Monasterolo, Mauro F. A. Adamo
Summary: This study presents a novel organocatalytic method for the desymmetrization of meso-aziridines without the need for external nucleophilic reagents. The process generates densely functionalized cyclic ketones, key intermediates for the preparation of Active Pharmaceutical Ingredients. The enantio-determining step is catalyzed by a bifunctional thiourea organocatalyst, enabling the synthesis of highly functionalized chiral amines not accessible with previous methods.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Yuriy Zatsikha, Briana R. Schrage, Tanner S. Blesener, Laurel A. Harrison, Christopher J. Ziegler, Victor N. Nemykin
Summary: In this study, a sterically strained 32 pi-electron antiaromatic bis-BODIPY macrocycle was prepared and characterized. The fluorescence in this macrocycle was quenched, unlike regular BODIPYs. The NMR spectra of the macrocycle showed broad signals due to the vibronic freedom of the p-divinylbenzene fragments. EPR spectra in solution and in solid state confirmed the closed-shell quinoidal structure of the macrocycle, ruling out its possible diradicaloid nature.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Sanjiv O. Tomer, Hemant P. Soni
Summary: In this study, the molecular structure of quinidine was modified and a chiral hemiester catalyst with high enantioselectivity and yield was successfully synthesized.
NEW JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Organic
Sayan Ray, Santanu Mukherjee
Summary: In this study, we present a new synthetic method for the enantioselective synthesis of ring-retentive bicyclo[4.1.0]heptane derivatives. This method involves a formal C(sp(2))-H alkylation using a nitroalkane as the alkylating agent. The reaction is catalyzed by a dihydroquinine-derived bifunctional tertiary aminosquaramide and yields products with high enantiomeric ratios.
Article
Chemistry, Multidisciplinary
Min Zhu, Hua-Jie Jiang, Illia Sharanov, Elisabeth Irran, Martin Oestreich
Summary: A desymmetrizing silylation of aromatic diols is achieved by using List's counteranion directed silylation technique for asymmetric silyl ether formation of phenol derivatives. The enantioselective discrimination of achiral 1,1'-biaryl-2,6-diols is enabled by a silylium-ion-like silicon electrophile generated from an allylic silane paired with an imidodiphosphorimidate (IDPi). The enantioselectivity of the desymmetrization is further improved by a downstream kinetic resolution, converting the monosilylated minor enantiomer into the corresponding bissilylated diol.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Rong-Bin Hu, Ying-Pong Lam, Wing-Hin Ng, Chun-Yuen Wong, Ying-Yeung Yeung
Summary: An alternative strategy of removing chloride anions from ruthenium trichloride using an organic zwitterionic compound has been reported in this study, and its application in the oxidation of alcohols, tetrahydroquinolines, and indolines has been successful. The performance of the zwitterion is superior to many common bases, and mechanistic studies show that it triggers the dissociation of chloride from ruthenium trichloride via nonclassical hydrogen bond interaction. Preliminary studies indicate that the zwitterion is applicable to catalytic transfer semi-hydrogenation.
Article
Chemistry, Physical
Zhihao Zhang, Yongwei Ni, Zhenjiang Li, Jun He, Xin Zou, Xin Yuan, Ziqi Liu, Shaoju Cao, Canliang Ma, Kai Guo
Summary: We developed a neutral organocatalyst, amino-cyclopro-penium halide, for the [3 + 2] cycloaddition of glycidol and isocyanate to prepare optically active oxazolidinone. The presence of an organic ion pair allowed for the coupling of glycidol with isocyanate followed by cyclization. The mild H-bonding coordination between the catalyst and substrate prevented non-selective ring-opening and racemization.
MOLECULAR CATALYSIS
(2023)
Article
Polymer Science
Tianfo Guo, Haoying Tong, Zhenjiang Li, Jie Sun, Yongqiang Li, Rui Yan, Bo Liu, Zhihao Zhang, Yuejia Zhu, Kai Guo
Summary: A polybenzoxazine (PBz) anchored with an N-4'-pyridyl group on the backbone was prepared and characterized, showing efficient catalytic activity in acylation, silylation, and tritylation reactions at room temperature. The catalyst exhibited high catalytic activity, good yields, and retained 85% activity after 4 recycles, demonstrating its potential as a versatile polymeric catalyst for various reactions.
EUROPEAN POLYMER JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Titouan Desrues, Jeremy Merad, Daniela Andrei, Jean-Marc Pons, Jean-Luc Parrain, Maurice Medebielle, Adrien Quintard, Cyril Bressy
Summary: This study reported an enantioselective organocatalyzed acylation of alpha,alpha-difluorohydrins using a commercially available chiral isothiourea, greatly improving the enantioselectivity of the kinetic resolution process through electrostatic fluorine-cation interactions. The method allows for the synthesis of various fluorinated alcohols with exquisite enantiocontrol, such as 4,4-difluoro-1,3-diols, as well as demonstrated compatibility between aromatic and fluorinated groups in providing enantioenriched adducts.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Esteban Matador, Javier Iglesias-Siguenza, David Monge, Pedro Merino, Rosario Fernandez, Jose M. Lassaletta
Summary: A highly enantio- and diastereoselective thiourea-catalyzed dearomatization of isoquinolines has been developed using N-tert-butylhydrazones as key neutral reagents, leading to the formation of appealing dihydroisoquinoline derivatives with excellent stereocontrol. Experimental and computational data support the generation of highly ordered complexes that play a crucial role in the selective and high-yielding transformations.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Polymer Science
Yuejia Zhu, Yongzhu Hu, Zhenjiang Li, Bo Liu, Yuanyuan Qu, Zhihao Zhang, Tianfo Guo, Yongqiang Li, Luoyu Gao, Kai Guo
Summary: By introducing 3-amino-1,2,4-benzo-thiadiazine-1,1-dioxide (ABTD) as a bidentate H-bond donor and triethylamine (TEA) as a mild Lewis base, successful control of polylactide (PLA) with predictable molecular weights and extremely narrow dispersities was achieved in room temperature solutions.
EUROPEAN POLYMER JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Sayan Ray, Subhajit Mondal, Santanu Mukherjee
Summary: In this study, a total synthesis of [3]-ladderanol was achieved using a novel desymmetrizing reaction strategy. The synthetic method is concise and efficient, and can be applied to the synthesis of similar molecules.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Chang-Qiu Guo, Chuan-Jun Lu, Li-Wen Zhan, Peng Zhang, Qi Xu, Jia Feng, Ren-Rong Liu
Summary: This study reports a new catalyst that successfully catalyzes the enantioselective coupling reaction between quinone esters and anilines, resulting in the formation of N-aryl quinone atropisomers with a unique intramolecular hydrogen bond. This method has the potential to be used for the synthesis of structurally diverse secondary amine atropisomers.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Bang-An Zhou, Xue-Ning Li, Chun-Lin Zhang, Zhi-Xiang Wang, Song Ye
Summary: The N-heterocyclic carbene-catalyzed enantioselective synthesis of axially chiral diaryl ethers via desymmetrization of prochiral 2-aryloxyisophthalaldehydes has been presented. This method exhibits mild reaction conditions, broad substrate scope, and excellent enantioselectivity. The utility of this methodology has been demonstrated through late-stage functionalization and various enantioretentive transformations.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Pharmacology & Pharmacy
Hiroki Hashizume, Tatsuki Fukami, Kanji Mishima, Hiroshi Arakawa, Kenji Mishiro, Yongjie Zhang, Masataka Nakano, Miki Nakajima
Summary: This study aimed to clarify the human ACS isoforms responsible for CoA-conjugation of NSAIDs by considering the hepatic expression levels of ACS isoforms. Among the 10 types of NSAIDs studied, propionic acid-class NSAIDs were found to be conjugated with CoA in the human liver, while NSAIDs in other classes did not exhibit this reaction. ACSL1 was identified as the most highly expressed ACS isoform in the human liver, and could catalyze the CoA conjugation of propionic acid-class NSAIDs, which may lead to toxicity through protein adduct formation.
BIOCHEMICAL PHARMACOLOGY
(2021)
Article
Biochemistry & Molecular Biology
Nurmaya Effendi, Kenji Mishiro, Kazuhiro Shiba, Seigo Kinuya, Kazuma Ogawa
Summary: This study aimed to develop peptide-based imaging probes for PDGFRβ and examined the effects of different linkers on their properties. The in vivo evaluation showed certain probes with higher cell uptake rates and stability, but insufficient tumor accumulation, calling for further probe modification for better in vivo imaging.
Article
Chemistry, Physical
Takuya Murai, Wenjie Lu, Toshifumi Kuribayashi, Kazuhiro Morisaki, Yoshihiro Ueda, Shohei Hamada, Yusuke Kobayashi, Takahiro Sasamori, Norihiro Tokitoh, Takeo Kawabata, Takumi Furuta
Summary: D-2-symmetric dirhodium(II) carboxylate catalysts bearing axially chiral binaphthothiophene delta-amino acid derivatives have been developed, with conformational control supported through chalcogen-bonding interactions providing well-defined and uniform asymmetric environments. These complexes act as asymmetric catalysts for stereoselective intramolecular C-H insertion to yield various cis-alpha,beta-diaryl gamma-lactones, with high diastereo- and enantioselectivities, and can also be used for short total syntheses of naturally occurring gamma-lactones.
Article
Chemistry, Multidisciplinary
Hisashi Hashimoto, Yoshihiro Ueda, Kiyosei Takasu, Takeo Kawabata
Summary: Catalyst-controlled substrate-selective silylation of alcohols is achieved independently of the reactivity of hydroxy group based on steric environment. The reaction shows high selectivity towards 1,5-amino alcohol derivatives and discriminating ability towards remote functionality at C(5) from reacting hydroxy groups in the silylation of pentanol analogues.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Review
Chemistry, Medicinal
Yoshihiro Ueda
Summary: The review summarizes recent research on site selectivity in the acylation of hydroxy groups and C-H amination, demonstrating the power of site-selective transformation in the synthesis of specific classes of compounds.
CHEMICAL & PHARMACEUTICAL BULLETIN
(2021)
Article
Chemistry, Medicinal
Kenji Mishiro, Ryuichi Nishii, Izumi Sawazaki, Tomoki Sofuku, Takeshi Fuchigami, Hitomi Sudo, Nurmaya Effendi, Akira Makino, Yasushi Kiyono, Kazuhiro Shiba, Junichi Taki, Seigo Kinuya, Kazuma Ogawa
Summary: Researchers attempted to develop nuclear imaging probes for detecting EGFR mutations. They designed and synthesized radioactive or nonradioactive osimertinib derivatives and evaluated their activity. The results showed that these derivatives accumulated significantly higher in tumors with mutations compared to normal tissues, but they also showed high accumulation in the lungs. Therefore, further structural modifications of the probes are needed.
JOURNAL OF MEDICINAL CHEMISTRY
(2022)
Article
Chemistry, Organic
Valluru Krishna Reddy, Keizo Kan, Yasser Samir Abdel-Khalek Sokeirik, Keisuke Yoshida, Atsushi Hirata, Masahiro Yamanaka, Yoshihiro Ueda, Takeo Kawabata
Summary: The method for kinetic resolution of 2,2'-disubstituted 1,1'-binaphthyl-8,8'-diamines was developed through enantioselective acylation of the amino group with chiral pyrrolidinopyridine organocatalysts. The accelerative enantioselective acylation was proposed to be due to multiple hydrogen-bonding interactions and pi-pi interaction between the catalyst and the diamines.
Article
Chemistry, Organic
Naruhiro Gondo, Ryuichi Hyakutake, Koki Fujimura, Yoshihiro Ueda, Katsuhiko Nakano, Ryosuke Tsutsumi, Masahiro Yamanaka, Takeo Kawabata
Summary: In this study, catalyst-controlled vinylogous aza-MBH reactions of vinylcyclopentenone were conducted, showing that DABCO-catalysis led to exclusive formation of alpha-adducts while DMAP-catalysis predominantly produced gamma-adducts. It was found that the rate-determining step for the DABCO-catalyzed reactions was the Mannich-type C-C bond forming step, while for the DMAP-catalyzed reactions, it appeared to be the beta-elimination step.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Cell Biology
Hiroya Kondo, Kenji Mishiro, Yuki Iwashima, Yujia Qiu, Akiko Kobayashi, Keesiang Lim, Takahiro Domoto, Toshinari Minamoto, Kazuma Ogawa, Munetaka Kunishima, Masaharu Hazawa, Richard W. Wong
Summary: This study identified a new compound called aminocyclopropenone that can block the activity of BRD4 in cancer cells, thereby inhibiting cell growth and transcriptional regulation. By inhibiting BRD4, this compound also reduces the size of the cell nucleus and decreases the level of nucleoporin NUP210. This research contributes to the development of new drugs for cancer treatment.
Article
Biochemistry & Molecular Biology
Hiroaki Echigo, Kenji Mishiro, Masayuki Munekane, Takeshi Fuchigami, Yoji Kitamura, Seigo Kinuya, Kazuma Ogawa
Summary: The study demonstrates that incorporating RGD peptides into oxo-platin enhances drug selectivity for cancer. Additionally, combining [I-123/124]10 and 9 for diagnostic imaging and therapy shows potential for cancer theranostics.
BIOORGANIC & MEDICINAL CHEMISTRY
(2022)
Article
Chemistry, Organic
Hisashi Hashimoto, Yoshihiro Ueda, Koki Fujimura, Kiyosei Takasu, Takeo Kawabata
Summary: Primary hydroxy groups exhibit higher reactivity than secondary ones, especially in trialkylsilylation. This study demonstrates that DMAP-catalyzed silylation of unprotected pyranosides exclusively occurs at the primary C(6)-OH, resulting in 6-O-silylates. In addition, catalyst ent-C1 enables the selective silylation of the secondary C(3)-OH of pyranosides.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Radiology, Nuclear Medicine & Medical Imaging
Saki Hirata, Kenji Mishiro, Takuma Higashi, Takeshi Fuchigami, Masayuki Munekane, Yasushi Arano, Seigo Kinuya, Kazuma Ogawa
Summary: Prostate cancer often metastasizes to the bone, making early detection and treatment of bone metastases important. In this study, a multifunctional radiotracer was developed to improve the sensitivity of detecting bone metastases in prostate cancer patients. The radiotracer showed high affinity for hydroxyapatite and PSMA-positive cells, and exhibited high accumulation in bone and PSMA-positive tumors. This study provides valuable information for developing radiotheranostic probes combining multiple carriers with different mechanisms.
NUCLEAR MEDICINE AND BIOLOGY
(2022)
Article
Chemistry, Organic
Naruhiro Gondo, Koki Fujimura, Ryuichi Hyakutake, Yoshihiro Ueda, Takeo Kawabata
Summary: Asymmetric regioselective vinylogous aza-Morita-Baylis-Hillman reactions were conducted using organocatalysis. The reactions between 3-vinylcyclopentenone and various aldimines, in the presence of chiral pyrrolidinopyridine catalysts, yielded 7-adducts with high regioselectivity and moderate enantioselectivity.
TETRAHEDRON LETTERS
(2023)
Article
Biochemistry & Molecular Biology
Mohamed Elsaid Nasr Elghobary, Masayuki Munekane, Kenji Mishiro, Takeshi Fuchigami, Kazuma Ogawa
Summary: Thermosensitive liposomes (TSLs) encapsulating I-125-labeled doxorubicin (DOX) were developed for Auger electron therapy, targeting cancer cell DNA. The radioiodinated DOX derivative [I-125]5 accumulated in the nuclei of cancer cells and showed potent cytotoxicity against Colon 26 cancer cells by Auger electrons. TSLs encapsulating [I-125]5 demonstrated efficient release at 42 degrees C and high uptake in the nuclei, suggesting their potential as an effective cancer therapy.
Article
Biochemistry & Molecular Biology
Kenji Mishiro, Mengfei Wang, Saki Hirata, Takeshi Fuchigami, Kazuhiro Shiba, Seigo Kinuya, Kazuma Ogawa
Summary: Sigma receptors are highly expressed on cancer cells, so radiolabeled sigma receptor ligands have been developed for cancer imaging and therapy. In this study, several new compounds were synthesized and evaluated for their affinity for sigma receptors, and promising sigma receptor-targeting probes were identified.
RSC MEDICINAL CHEMISTRY
(2022)
