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Hussain A, Sravanthi R, Katta S, Ramachary DB. Two-step, high-yielding total synthesis of antibiotic pyrones. Org Biomol Chem 2024; 22:554-560. [PMID: 38116605 DOI: 10.1039/d3ob01923c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
A simple two-step dialkylation protocol was developed to synthesize biologically active antibiotics photopyrones, pseudopyronines, and violapyrones from bio-renewable triacetate lactone in excellent yields. These pyrones are functionally modified into another set of pyrone natural products by a single O-methylation reaction. The high-yielding gram scale synthesis of four natural products [pseudopyronine A, photopyrone A, pseudopyronine B and photopyrone C] demonstrated the viability for industrial applications.
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Affiliation(s)
- Akram Hussain
- Catalysis Laboratory, School of Chemistry, University of Hyderabad, Hyderabad-500 046, India.
| | - Revoju Sravanthi
- Catalysis Laboratory, School of Chemistry, University of Hyderabad, Hyderabad-500 046, India.
- Pharmacognosy and Phytochemistry Division, Gitam Institute of Pharmacy, Gitam Deemed to be University, Visakhapatnam, 530 045, Andhra Pradesh, India
| | - Sunitha Katta
- Pharmacognosy and Phytochemistry Division, Gitam Institute of Pharmacy, Gitam Deemed to be University, Visakhapatnam, 530 045, Andhra Pradesh, India
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2
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Bagherinejad A, Alizadeh A. A review of the synthetic strategies toward spirobarbiturate-fused 3- to 7-membered rings. Org Biomol Chem 2022; 20:7188-7215. [PMID: 36070341 DOI: 10.1039/d2ob01326f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Spiro-connected hexahydropyrimidine-2,4,6-trione heterocyclic rings have received increasing attention from the viewpoint of biological activity and synthetic methods due to the importance of the rigid heterocyclic system and unique orientation of the functional substituents. Since 1900, numerous studies have exploited the synthesis of various spirobarbiturate-fused carbo- and heterocycles by applying different strategies. Due to the importance of barbiturate-based olefins as activated alkenes, these substrates have been utilized in many reactions. In addition, the nucleophilic addition of 1,3-disubstituted barbituric acid to different electrophiles has been applied to prepare highly functionalized spirobarbiturate scaffolds. This short review highlights various strategies for synthesizing spirobarbiturate-fused 3- to 7-membered carbo- and heterocyclic rings and some catalytic diastereoselective and enantioselective chemical reactions to access chiral compounds. The sections are divided by the incorporation of 3- to 7-membered heterocyclic or carbocyclic rings into a spirobarbiturate scaffold, and are presented in different subsections depending on the mechanistic details.
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Affiliation(s)
- Akram Bagherinejad
- Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.
| | - Abdolali Alizadeh
- Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.
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3
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Zheng Z, Deng H, Cai Z, Liao X, Xu S. Synthesis of the Octameric Ring Containing Compound Caulerpin Using a Knoevenagel Reaction Catalyzed by an Amino Acid ‐ Ionic Liquid Solvent. ChemistrySelect 2022. [DOI: 10.1002/slct.202201381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Zhang‐Fan Zheng
- Department of Chemistry College of Chemistry and Materials Science Jinan University Guangzhou 510632 P. R. China
| | - Hong Deng
- Department of Chemistry College of Chemistry and Materials Science Jinan University Guangzhou 510632 P. R. China
| | - Zi‐Jie Cai
- Department of Chemistry College of Chemistry and Materials Science Jinan University Guangzhou 510632 P. R. China
| | - Xiao‐Jian Liao
- Department of Chemistry College of Chemistry and Materials Science Jinan University Guangzhou 510632 P. R. China
| | - Shi‐Hai Xu
- Department of Chemistry College of Chemistry and Materials Science Jinan University Guangzhou 510632 P. R. China
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4
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Peraka S, Gorachand B, Hussain A, Sravanthi R, Ramachary DB. Organocatalytic One‐pot Synthesis of Pseudo‐Terpenoids. European J Org Chem 2022. [DOI: 10.1002/ejoc.202200674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Swamy Peraka
- University of Hyderabad School of Chemistry INDIA
| | | | | | | | - Dhevalapally B. Ramachary
- University of Hyderabad School of Chemistry Prof. C.R.Rao RoadCentral University PostGachi BowliHyderabad 500 046 Hyderabad INDIA
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Kamanna K. Organocatalysts based on natural and modified amino acids for asymmetric reactions. PHYSICAL SCIENCES REVIEWS 2022. [DOI: 10.1515/psr-2021-0026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Small organic molecules predominantly containing C, H, O, N, S and P element are found promising molecule to accelerate chemical reactions and are named organocatalysis. In addition, these organocatalysts are easy availability, stable in water and air, inexpensive, and low toxicity, which confer a huge direct application in organic synthesis when compared to transition metal catalyzed reactions and becoming powerful tools in the construction of a selective chiral product. Interest on organocatalysis is spectacularly increased since last two decades, due to the novelty of the concept and selectivity. Based on the nature of the organocatalysts used, they are classified in to four major classes, among them one of the types is amino acids derived organocatalysts. Natural amino acids are playing important role in building blocks of protein construction, and also intermediate products of the metabolism. α-Amino acid is a molecule, that contains both amine and carboxyl functional group. Their particular structural characteristic determines their role in protein synthesis, and bifunctional asymmetric catalysts for stereoselective synthesis. Two functional groups present on a single carbon acting as an acid and base, which promote chemical transformations in concert similar to the enzymatic catalysis. The post translational derivatives of natural α-amino acids include 4-hydroxy-L-proline and 4-amino-L-proline scaffolds, and its synthetic variants based organocatalysts, whose catalytic activity is well documented. This chapter discussed past and present development of the organocatalysts derived from natural and modified amino acids for various important organic transformations reviewed.
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Affiliation(s)
- Kantharaju Kamanna
- Department of Chemistry , Rani Channamma University , Vidyasangama , P-B, NH-4 , Belagavi 591156 , Karnataka , India
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6
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Zhai JS, Du DM. Bifunctional thiourea-catalyzed asymmetric [3 + 2] annulation reactions of 2-isothiocyanato-1-indanones with barbiturate-based olefins. Beilstein J Org Chem 2022; 18:25-36. [PMID: 35047080 PMCID: PMC8744461 DOI: 10.3762/bjoc.18.3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 12/13/2021] [Indexed: 12/31/2022] Open
Abstract
Bifunctional thiourea-catalyzed asymmetric [3 + 2] annulation reactions of 2-isothiocyanato-1-indanones with barbiturate-based olefins have been developed to afford chiral dispiro[indene-pyrrolidine-pyrimidine]s. Through this strategy, the target products could be obtained in good to excellent yields with excellent stereoselectivities. In addition, the synthetic utility was verified through a gram-scale synthesis, one-pot three-component reactions and further transformation experiments of the products.
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Affiliation(s)
- Jiang-Song Zhai
- School of Chemistry and Chemical Engineering, Beijing Institute of Technology, No.5 Zhongguancun South Street, Beijing 100081, People’s Republic of China
| | - Da-Ming Du
- School of Chemistry and Chemical Engineering, Beijing Institute of Technology, No.5 Zhongguancun South Street, Beijing 100081, People’s Republic of China
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Madhavachary R, Mallik R, Ramachary DB. Organocatalytic Enantiospecific Total Synthesis of Butenolides. Molecules 2021; 26:molecules26144320. [PMID: 34299595 PMCID: PMC8306825 DOI: 10.3390/molecules26144320] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/08/2021] [Accepted: 07/14/2021] [Indexed: 11/16/2022] Open
Abstract
Biologically important, chiral natural products of butenolides, (−)-blastmycinolactol, (+)-blastmycinone, (−)-NFX-2, (+)-antimycinone, lipid metabolites, (+)-ancepsenolide, (+)-homoancepsenolide, mosquito larvicidal butenolide and their analogues were synthesized in very good yields in a sequential one-pot manner by using an organocatalytic reductive coupling and palladium-mediated reductive deoxygenation or organocatalytic reductive coupling and silica-mediated reductive deamination as the key steps.
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Direct Catalytic Asymmetric Synthesis of Disubstituted 4-Oxocyclohexanecarbaldehydes from Acetone and Cinnamaldehyde Derivatives. Org Lett 2021; 23:1566-1571. [DOI: 10.1021/acs.orglett.0c04277] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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9
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Wang CC, Zhou J, Ma ZW, Chen XP, Chen YJ. Synthesis of spirobarbiturate-pyrrolidinones via a domino aza-Michael/S N2 cyclization of barbiturate-derived alkenes with N-alkoxy α-haloamides. Org Biomol Chem 2019; 17:9200-9208. [PMID: 31596301 DOI: 10.1039/c9ob01992h] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A highly efficient domino aza-MIRC (Michael Induced Ring Closure) reaction between barbiturate-derived alkenes and N-alkoxy α-haloamides has been achieved in moderate to excellent yields. This reaction proceeds smoothly under mild conditions via a domino aza-Michael addition/intramolecular SN2 sequence, providing a practical tool in the synthesis of bioactive molecules spirobarbiturate-3-pyrrolidinones.
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Affiliation(s)
- Chuan-Chuan Wang
- Faculty of Science, Henan University of Animal Husbandry and Economy, No. 2 Yingcai Street, Huiji District, Zhengzhou 450044, Henan, PR China
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10
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An T, Du D. Chiral Squaramide Catalyzed Asymmetric [3+2] Cycloaddition Reaction for Synthesis of Trifluoromethylated Barbituric Acid Derivatives. ChemistrySelect 2019. [DOI: 10.1002/slct.201903146] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Tian‐Li An
- School of Chemistry and Chemical EngineeringBeijing Institute of Technology 5 South Zhongguancun Street Beijing 100081 P. R. China
| | - Da‐Ming Du
- School of Chemistry and Chemical EngineeringBeijing Institute of Technology 5 South Zhongguancun Street Beijing 100081 P. R. China
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11
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Frankowski S, Gajda T, Albrecht Ł. Isothiocyanate Strategy for the Synthesis of Quaternary α-Amino Acids Bearing a Spirocyclic Ring System. Adv Synth Catal 2018. [DOI: 10.1002/adsc.201701642] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Sebastian Frankowski
- Institute of Organic Chemistry; Department of Chemistry; Lodz University of Technology; Zeromskiego 116, 90-924 Łódź Poland
| | - Tadeusz Gajda
- Institute of Organic Chemistry; Department of Chemistry; Lodz University of Technology; Zeromskiego 116, 90-924 Łódź Poland
| | - Łukasz Albrecht
- Institute of Organic Chemistry; Department of Chemistry; Lodz University of Technology; Zeromskiego 116, 90-924 Łódź Poland
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12
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Anebouselvy K, Shruthi KS, Ramachary DB. Asymmetric Supramolecular Organocatalysis: A Complementary Upgrade to Organocatalysis. European J Org Chem 2017. [DOI: 10.1002/ejoc.201700611] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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13
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Ramachary DB, Reddy PS, Shruthi KS, Madhavachary R, Reddy PVG. A Brønsted Acid-Primary Amine as a Synergistic Catalyst for Stereoselective Asymmetric Diels-Alder Reactions. European J Org Chem 2016. [DOI: 10.1002/ejoc.201601011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Dhevalapally B. Ramachary
- Catalysis Laboratory; School of Chemistry; University of Hyderabad; 500046 Hyderabad Telangana India
| | - P. Sreekanth Reddy
- Department of Chemistry; Yogi Vemana University; 516003 Kadapa Andhra Pradesh India
| | - Kodambahalli S. Shruthi
- Catalysis Laboratory; School of Chemistry; University of Hyderabad; 500046 Hyderabad Telangana India
| | - R. Madhavachary
- Catalysis Laboratory; School of Chemistry; University of Hyderabad; 500046 Hyderabad Telangana India
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14
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Zhao HW, Tian T, Pang HL, Li B, Chen XQ, Yang Z, Meng W, Song XQ, Zhao YD, Liu YY. Organocatalytic [3+2] Cycloadditions of Barbiturate-Based Olefins with 3-Isothiocyanato Oxindoles: Highly Diastereoselective and Enantioselective Synthesis of Dispirobarbiturates. Adv Synth Catal 2016. [DOI: 10.1002/adsc.201600270] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Hong-Wu Zhao
- College of Life Science and Bio-engineering; Beijing University of Technology; Beijing 100124 People's Republic of China
| | - Ting Tian
- College of Life Science and Bio-engineering; Beijing University of Technology; Beijing 100124 People's Republic of China
| | - Hai-Liang Pang
- College of Life Science and Bio-engineering; Beijing University of Technology; Beijing 100124 People's Republic of China
| | - Bo Li
- College of Life Science and Bio-engineering; Beijing University of Technology; Beijing 100124 People's Republic of China
| | - Xiao-Qin Chen
- College of Life Science and Bio-engineering; Beijing University of Technology; Beijing 100124 People's Republic of China
| | - Zhao Yang
- College of Life Science and Bio-engineering; Beijing University of Technology; Beijing 100124 People's Republic of China
| | - Wei Meng
- College of Life Science and Bio-engineering; Beijing University of Technology; Beijing 100124 People's Republic of China
| | - Xiu-Qing Song
- College of Life Science and Bio-engineering; Beijing University of Technology; Beijing 100124 People's Republic of China
| | - Yu-Di Zhao
- College of Life Science and Bio-engineering; Beijing University of Technology; Beijing 100124 People's Republic of China
| | - Yue-Yang Liu
- College of Life Science and Bio-engineering; Beijing University of Technology; Beijing 100124 People's Republic of China
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15
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Ramachary DB, Krishna PM. Asymmetric Synthesis of Nature-Inspired Bioactive Spiro Compounds through Organocatalytic Diels-Alder Reactions. ASIAN J ORG CHEM 2016. [DOI: 10.1002/ajoc.201600145] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
| | - Patoju M. Krishna
- Catalysis Laboratory; School of Chemistry; University of Hyderabad; Hyderabad 500 046 India
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16
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Berini C, Sebban M, Oulyadi H, Sanselme M, Levacher V, Brière JF. Organocatalyzed Multicomponent Synthesis of Isoxazolidin-5-ones. Org Lett 2015; 17:5408-11. [DOI: 10.1021/acs.orglett.5b02755] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Christophe Berini
- Normandie Univ, COBRA, UMR 6014 et FR 3038; Univ Rouen; INSA Rouen; CNRS, IRCOF, 1 rue Tesnière, 76821 Mont Saint Aignan Cedex, France
| | - Muriel Sebban
- Normandie Univ, COBRA, UMR 6014 et FR 3038; Univ Rouen; INSA Rouen; CNRS, IRCOF, 1 rue Tesnière, 76821 Mont Saint Aignan Cedex, France
| | - Hassan Oulyadi
- Normandie Univ, COBRA, UMR 6014 et FR 3038; Univ Rouen; INSA Rouen; CNRS, IRCOF, 1 rue Tesnière, 76821 Mont Saint Aignan Cedex, France
| | - Morgane Sanselme
- Normandie Univ, Laboratoire SMS- EA3233, Univ Rouen, F-76821, Mont Saint Aignan, France
| | - Vincent Levacher
- Normandie Univ, COBRA, UMR 6014 et FR 3038; Univ Rouen; INSA Rouen; CNRS, IRCOF, 1 rue Tesnière, 76821 Mont Saint Aignan Cedex, France
| | - Jean-François Brière
- Normandie Univ, COBRA, UMR 6014 et FR 3038; Univ Rouen; INSA Rouen; CNRS, IRCOF, 1 rue Tesnière, 76821 Mont Saint Aignan Cedex, France
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Han B, Huang W, Ren W, He G, Wang JH, Peng C. Asymmetric Synthesis of Cyclohexane-Fused Drug-Like Spirocyclic Scaffolds Containing Six Contiguous Stereogenic CentersviaOrganocatalytic Cascade Reactions. Adv Synth Catal 2015. [DOI: 10.1002/adsc.201400764] [Citation(s) in RCA: 101] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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18
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Madhavachary R, Ramachary DB. High-Yielding Total Synthesis of Sexually Deceptive Chiloglottones and Antimicrobial Dialkylresorcinols through an Organocatalytic Reductive Coupling Reaction. European J Org Chem 2014. [DOI: 10.1002/ejoc.201403128] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Ramachary DB, Venkaiah C, Reddy YV. High-yielding sequential one-pot synthesis of chiral and achiral α-substituted acrylates via a metal-free reductive coupling reaction. Org Biomol Chem 2014; 12:5400-6. [PMID: 24934801 DOI: 10.1039/c4ob00667d] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A general process for the high-yielding synthesis of substituted chiral and achiral α-substituted acrylates was achieved through the sequential one-pot combination of a metal-free reductive coupling reaction followed by an Eschenmoser methylenation. The proline catalyzed reaction of Meldrum's acid, aldehydes and Hantzsch ester followed by methylenation was successful with Eschenmoser's salt in the presence of an alcohol solvent. Herein, we have shown the high-yielding synthesis of privileged building blocks from chiral/achiral α-substituted acrylates and shown them to be very good intermediates in the pharmaceuticals and natural products synthesis.
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Ramachary DB, Reddy PS, Prasad MS. Neighboringortho-Hydroxy Group Directed Catalytic Asymmetric Triple Domino Reactions of Acetaldehyde with (E)-2-(2-Nitrovinyl)phenols. European J Org Chem 2014. [DOI: 10.1002/ejoc.201402182] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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21
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Li Y, Xue Z, Ye W, Liu J, Yao J, Wang C. One-pot multicomponent synthesis of highly functionalized piperidines from substituted β-nitrostyrenes, Meldrum's acid, aromatic aldehydes, and ammonium acetate. ACS COMBINATORIAL SCIENCE 2014; 16:113-9. [PMID: 24521510 DOI: 10.1021/co4001502] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
An efficient and straightforward synthetic protocol has been developed for the diversity-oriented synthesis of highly functionalized piperidines containing a Meldrum's acid moiety via pseudo five-component reaction between aromatic aldehydes, ammonium acetate, substituted β-nitrostyrenes and Meldrum's acid for the generation of a wide range of structurally interesting and pharmacologically significant compounds.
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Affiliation(s)
- Yan Li
- School of Chemistry and Chemical
Engineering, Yangzhou University, 180 Siwangting Street, Yangzhou 225002, P. R. China
| | - Zhiheng Xue
- School of Chemistry and Chemical
Engineering, Yangzhou University, 180 Siwangting Street, Yangzhou 225002, P. R. China
| | - Weijian Ye
- School of Chemistry and Chemical
Engineering, Yangzhou University, 180 Siwangting Street, Yangzhou 225002, P. R. China
| | - Juanjuan Liu
- School of Chemistry and Chemical
Engineering, Yangzhou University, 180 Siwangting Street, Yangzhou 225002, P. R. China
| | - Juan Yao
- School of Chemistry and Chemical
Engineering, Yangzhou University, 180 Siwangting Street, Yangzhou 225002, P. R. China
| | - Cunde Wang
- School of Chemistry and Chemical
Engineering, Yangzhou University, 180 Siwangting Street, Yangzhou 225002, P. R. China
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22
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Alemán J, Cabrera S. Applications of asymmetric organocatalysis in medicinal chemistry. Chem Soc Rev 2013; 42:774-93. [DOI: 10.1039/c2cs35380f] [Citation(s) in RCA: 325] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Ramachary DB, Madhavachary R, Prasad MS. Observation of neighboring ortho-hydroxyl group participation in organocatalytic asymmetric sequential Michael-lactonization reactions: synthesis of highly substituted chiral spirodihydrocoumarins. Org Biomol Chem 2012; 10:5825-9. [PMID: 22391626 DOI: 10.1039/c2ob07122c] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A general approach to asymmetric synthesis of highly substituted spirodihydrocoumarins with a quaternary stereocenter was achieved through neighboring ortho-hydroxyl group induced sequential Michael-lactonization reactions on 2-(2-nitrovinyl)phenols with alkyl cyclopentanone-2-carboxylates in the presence of a catalytic amount of quinine-NH-thiourea followed by p-TSA.
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Ramachary DB, Venkaiah C, Krishna PM. Discovery of 2-aminobuta-1,3-enynes in asymmetric organocascade catalysis: construction of drug-like spirocyclic cyclohexanes having five to six contiguous stereocenters. Chem Commun (Camb) 2012; 48:2252-4. [PMID: 22252651 DOI: 10.1039/c2cc17219d] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We present herein for the first time the asymmetric synthesis of drug-like spiranes through reflexive-Michael reaction by using 2-aminobuta-1,3-enyne catalysis under mild conditions.
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Ramachary DB, Mondal R, Madhavachary R. Direct catalytic asymmetric synthesis of highly functionalized (2-ethynylphenyl)alcohols via Barbas–List aldol reaction: scope and synthetic applications. Org Biomol Chem 2012; 10:5094-101. [DOI: 10.1039/c2ob25563d] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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