Article
Chemistry, Organic
Julia O. Strelnikova, Alexander N. Koronatov, Nikolai Rostovskii, Alexander F. Khlebnikov, Olesya Khoroshilova, Mariya A. Kryukova, Mikhail S. Novikov
Summary: The domino reaction catalyzed by Rh-2(Piv)(4) leads to the formation of N-sulfonylated (Z)-2-(2-aminovinyl)imidazoles, providing a direct and flexible access to the desired compounds.
Article
Chemistry, Organic
Nan-Fang Mo, Ying Zhang, Zheng-Hui Guan
Summary: An asymmetric organocatalyzed three-component Povarov reaction has been developed to construct azaspirocycles. A chiral phosphoric acid catalyst with a unique structure was highly efficient in the reaction, leading to a wide range of azaspirocycles in high yields and excellent enantioselectivities. This reaction has expanded the scope of the traditional Povarov reaction.
Review
Chemistry, Applied
Maxim G. Vinogradov, Olga V. Turova, Sergei G. Zlotin
Summary: This review retrospectively considers the pivotal achievements and recent advances in catalytic asymmetric aza-DAR reported up to 2020, showcasing their potency for enantioselective synthesis of useful chiral piperidine, quinoline, pyridazine, oxazine, and oxadiazine derivatives. The data are systematized based on key electron transfer modes and attainable heterocyclic products, with significant attention to activation strategies and plausible reaction pathways over stereoselective cyclization processes. The review contains 310 references and 122 synthetic schemes.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Organic
Rafael G. Uceda, Esther Roldan-Molina, Jorge A. R. Navarro, J. Enrique Oltra
Summary: This study explores the use of electron-deficient dienes as substrates in the aza Diels-Alder reaction, showing that the amide group significantly influences the yield of the reaction products.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Jie Ouyang, Rajat Maji, Markus Leutzsch, Benjamin Mitschke, Benjamin List
Summary: Here, we report the design of a highly enantioselective, catalytic (4 + 3) cycloaddition reaction enabled by strong and confined IDPi Lewis acids. This reaction allows the synthesis of novel compounds with multiple stereocenters from gem-dialkyl 2-indolylalcohols and dienolsilanes. The method exhibits broad substrate scope and versatile downstream chemical modifications. Density functional theory-supported mechanistic studies reveal the significance of the in-situ generated silylium species in an overall concerted yet asynchronous cycloaddition.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Physical
Victor Laina-Martin, Jorge Humbrias-Martin, Ruben Mas-Balleste, Jose A. Fernandez-Salas, Jose Aleman
Summary: A highly efficient enantioselective inverse-electron-demand aza-Diels-Alder reaction has been developed, allowing the synthesis of benzofuran-fused 2-piperidinol derivatives with three contiguous stereocenters in a highly selective manner. Density functional theory calculations support the reaction mechanism and reveal the mode of action of the hydrogen-bond donor.
Article
Chemistry, Multidisciplinary
Masao Ohashi, Dan Tan, Jiayan Lu, Cooper S. Jamieson, Daiki Kanayama, Jiahai Zhou, K. N. Houk, Yi Tang
Summary: The synthesis of cis-decalin structures using [4 + 2] cycloaddition with high stereoselectivity is challenging. In this study, we investigated the biosynthetic pathway of the fungal natural product fischerin (1) and identified a novel pericyclase, FinI, which catalyzes this reaction. The cocrystal structure of FinI, a predicted O-methyltransferase, with the product and SAM provides valuable insights into the natural formation of cis-decalin.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Yuan-He Li, Su-Lei Zhang, Yong Lu, Bo Xiao, Tian-Yu Sun, Qian-Qian Xu, Jia-Hua Chen, Zhen Yang
Summary: A highly enantioselective catalytic system for exo-Diels-Alder reactions was developed using bispyrrolidine diboronates(BPDB). Activated by various Lewis or Bronsted acids, BPDB can catalyze highly stereoselective asymmetric exo-Diels-Alder reactions. The catalyst can also distinguish between different binding sites to achieve highly regioselective reactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Depeng Duan, Huixin Qiu, Mengdie Tang, Ran Song, Wen Si, Daoshan Yang, Jian Lv
Summary: This study reports a [4+2] cycloaddition catalyzed by Lewis acid HfCl4, leading to high yields of polysubstituted 4H-pyrans. The reaction conditions are mild and exhibit excellent selectivity.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Daniel P. Schwinger, Thomas Pickl, Thorsten Bach
Summary: Cyclohept-1-ene-1-carbaldehyde undergoes photoinduced E & RARR; Z isomerization at & lambda; =350 nm. The ring strain facilitates various reactions, including Diels-Alder cycloadditions, [3 + 2] cycloadditions, and enereactions. The products obtained are trans-fusedat the cycloheptane core and yield up to 82%. Single crystal X-ray analyses confirm the structure and relative configuration. In the presence of BF3 and 2,3-dimethylbuta-1,3-diene, cyclohept-1-ene-1-carbaldehyde undergoes a stereoselective rearrangement to form a tricyclic ketone (87%).
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Yan Jiang, Hao-Jie Ma, Xue-Long Wang, Yi Yang
Summary: A Yb(OTf)(3)-catalyzed formal (4 + 3) cycloaddition reaction was successfully achieved using donor-acceptor cyclopropanes and 3-benzylideneindoline-2-thiones as reactants. Functionalized 5,10-dihydro-2H-thiepino[2,3-b]indole derivatives were synthesized with good yields and moderate to good diastereoselectivity. This reaction represents the first (4 + 3) cycloaddition of 3-benzylideneindoline-2-thiones.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Qun Zhao, Yao Li, Qing-Xia Zhang, Jin-Pei Cheng, Xin Li
Summary: The highly enantioselective aza-Diels-Alder reaction of 2-aryl-3H-indol-3-ones with unactivated dienes using a B(C6F5)(3)/chiral phosphoric acid catalyst system under mild conditions offers rapid access to a broad scope of tetrahydropyridine derivatives with excellent outcomes. The reaction is efficient, with maintained enantioselectivity even at lower catalyst loadings of 0.1 mol %. DFT calculations provide convincing evidence for the interpretation of stereoselection.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Aurapat Ngamnithiporn, Padon Chuentragool, Poonsakdi Ploypradith, Somsak Ruchirawat
Summary: This article reports the development of a novel three-component aza-Diels-Alder reaction, employing sultines, aldehydes, and amines as substrates. By using Cu(OTf)(2) as a Lewis acid catalyst and the in situ generation of imines, a wide range of polysubstituted tetrahydro-isoquinoline derivatives can be easily prepared from readily available precursors. The synthetic utility of these products is demonstrated through various product transformations, including the synthesis of tricyclic N-heterocycles.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Lei Yu, Wenhai Li, Anyawan Tapdara, Sara Helen Kyne, Mandeep Harode, Rasool Babaahmadi, Alireza Ariafard, Philip Wai Hong Chan
Summary: An efficient chiral gold(I) complex-catalyzed synthetic method for the regio- and enantioselective nitroso-Diels-Alder (NDA) reaction of 1,6-diyne esters with nitrosobenzenes is described. The reaction provides access to a wide range of 3,5,6,8a-tetrahydro-1H-benzo[c][1,2]oxazines as a single regioisomer with high yields and enantiomeric excess values.
Article
Chemistry, Multidisciplinary
Wei-Ling Jiang, Bin Huang, Meng-Xiang Wu, Ye-Kai Zhu, Xiao-Li Zhao, Xueliang Shi, Hai-Bo Yang
Summary: The preparation of stable MOFs with organic radicals is challenging due to the reactivity of most organic radicals. A novel MOF containing phenazine radical cations was successfully synthesized using a post-synthetic modification strategy. The resulting MOF demonstrated high catalytic activity in aza-Diels-Alder reactions and excellent stability and recyclability, suggesting the potential of the developed strategy for preparing radical-based MOFs for heterogeneous catalysis in organic synthesis.
CHEMISTRY-AN ASIAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Chandra S. Azad, Vishal M. Balaramnavar, Imran A. Khan, Pawan K. Doharey, Jitendra K. Saxena, Anil K. Saxena
Article
Chemistry, Multidisciplinary
Shahi Imam Reja, Imran A. Khan, Vandana Bhalla, Manoj Kumar
CHEMICAL COMMUNICATIONS
(2016)
Article
Chemistry, Medicinal
Shome S. Bhunia, Ankita Misra, Imran A. Khan, Stuti Gaur, Manish Jain, Surendra Singh, Aaruni Saxena, Thomas Hohlfield, Madhu Dikshit, Anil K. Saxena
JOURNAL OF MEDICINAL CHEMISTRY
(2017)
Article
Chemistry, Organic
Chandra S. Azad, Imran A. Khan, Anudeep K. Narula
ORGANIC & BIOMOLECULAR CHEMISTRY
(2016)
Article
Chemistry, Physical
Harnimarta Deol, Subhamay Pramanik, Manoj Kumar, Imran A. Khan, Vandana Bhalla
Article
Chemistry, Multidisciplinary
Tarlok Singh Banipal, Amandeep Kaur, Imran Ahmd Khan, Parampaul Kaur Banipal
Article
Spectroscopy
Amandeep Kaur, Imran Ahmd Khan, Parampaul Kaur Banipal, Tarlok Singh Banipal
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2018)
Article
Chemistry, Applied
Sugandha Sharma, Imran A. Khan, Anil K. Saxena
ADVANCED SYNTHESIS & CATALYSIS
(2013)
Article
Chemistry, Inorganic & Nuclear
Puja Prasad, Imran Khan, Pijus K. Sasmal, Debasis Koley, Paturu Kondaiah, Akhil R. Chakravarty
DALTON TRANSACTIONS
(2013)
Article
Chemistry, Organic
Imran A. Khan, Anil K. Saxena
JOURNAL OF ORGANIC CHEMISTRY
(2013)
Article
Chemistry, Physical
Asher M. Siddiqui, Anam Khalid, Arif Khan, Chandra S. Azad, Mohd Samim, Imran A. Khan
Article
Chemistry, Multidisciplinary
Swarna Dabral, Imran Ahmd Khan, Tarun Pant, Sabina Khan, Prem Prakash, Suhel Parvez, Nilanjan Saha
Summary: Antidiabetic drugs that also inhibit angiogenesis may help diabetic patients prevent complications such as cancer. A study investigated the effects of saroglitazar on angiogenesis using the CAM assay and identified its mode of action on protein networks. The study provides a new approach for studying angiogenesis using CAM assays and identifies the off-target use of saroglitazar to inhibit angiogenesis using system biology and network pharmacology.
Meeting Abstract
Ophthalmology
Ruth Jones, Imran Khan, Yashin Ramkissoon, Stephen Winder
Meeting Abstract
Ophthalmology
Rohini Nair, Murali Mohan Sagar Balla, Imran Khan, Ravi Kiran Reddy Kalathur, Paturu Kondaiah, Santosh Honavar, Mohammad Ali, Geeta Vemuganti
INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE
(2013)
