1035455-07-2Relevant academic research and scientific papers
Br?nsted acid promoted intramolecular cyclization of O-alkynyl benzoic acids: Concise total synthesis of exserolide F
Dumpala, Mohan,Kadari, Lingaswamy,Krishna, Palakodety Radha
supporting information, p. 2403 - 2408 (2018/08/29)
Herein we report the stereoselective total synthesis of Exserolide F. The key step involves triflic acid catalyzed highly regioselective intramolecular cyclization of an O-alkynyl benzoic acid derivative to accomplish the core isocoumarin skeleton of the natural product via 6-endo-dig mode of cyclization. The other important steps are: Sharpless asymmetric epoxidation, Barbier propargylation, Sonogashira coupling en route to access the O-alkynyl benzoic acid derivative.
Gold(I)-Catalyzed Cyclization for the Synthesis of 8-Hydroxy-3- substituted Isocoumarins: Total Synthesis of Exserolide F
Mallampudi, N. Arjunreddy,Reddy, G. Sudhakar,Maity, Saurabh,Mohapatra, Debendra K.
, p. 2074 - 2077 (2017/04/28)
A highly regioselective gold(I)-catalyzed 6-endo-dig cyclization of 2,2-dimethyl-5-(alkynyl)-4H-benzo[d][1,3]dioxin-4-ones for the synthesis of 8-hydroxy-3-substituted isocoumarins is described. Key features of the reaction include the broad substrate scope, scalability, and tolerance for protecting groups. The synthetic utility of this novel method is demonstrated by the first total synthesis of exserolide F, an isocoumarin-containing polyol natural product.
Total synthesis of the 2,6-disubstituted piperidine alkaloid (-)-andrachcinidine
Radha Krishna, Palakodety,Reddy, Bonepally Karunakar
, p. 758 - 763 (2013/07/25)
The total synthesis of the 2,6-disubstituted piperidine alkaloid (-)-andrachcinidine is reported using Keck's asymmetric allylation, Sharpless epoxidation, nucleophilic substitution, and intramolecular aza-Michael addition as the key steps.
Total synthesis of the antifungal antibiotic PF1163A
Krishna, Palakodety Radha,Srinivas, Palabindela
experimental part, p. 769 - 774 (2012/09/05)
The total synthesis of a novel antifungal antibiotic PF1163A is reported utilising Keck asymmetric allylation, Sharpless kinetic resolution, regioselective epoxide-ring opening, esterification and ring-closing metathesis as the key reactions.
Total synthesis of (+)-neopeltolide by a Prins macrocyclization
Woo, Sang Kook,Kwon, Min Sang,Lee, Eun
, p. 3242 - 3244 (2008/12/23)
(Chemical Equation Presented) Rings within rings: The total synthesis of (+)-neopeltolide was accomplished by employing an intramolecular Prins macrocyclization of an aldehydic homoallylic alcohol intermediate (see scheme).
A stereoselective total synthesis of (-)-andrachcinidine via an olefin cross-metathesis protocol
Radha Krishna, Palakodety,Dayaker
, p. 7279 - 7282 (2008/03/13)
A stereoselective total synthesis of 1-(2S,6R)-6-[(2S)-2-hydroxypentyl]-hexahydro-2-pyridinylacetone, (-)-andrachcinidine is reported. The strategy utilizes olefin cross-metathesis and intramolecular SN2 cyclization as the key steps.
[1,3]-Transfer of chirality during the nicholas reaction in γ-benzyloxy propargylic alcohols
Diaz, David D.,Ramirez, Miguel A.,Martin, Victor S.
, p. 2593 - 2606 (2008/02/07)
A highly regio- and stereoselective intramolecular [1.5]-hydrogentransfer process is described. Treatment of γ-benzyl-protccted Co 2(CO)6-α,γ-acetylenic diols with BF 3·OEt2 provides bis-homopropargylic alcohols. The reaction occurs within seconds, tolerates a wide range of functionalities, and provides good yields. When the ether group is located at a stereochemically defined carbon atom, the rearrangement occurs with high stereoselectivity, transferring the chirality of the carbinol center to the newly created stereocenter. The cleavage of the benzyloxy group is totally regioselective when additional benzyl ethers are present. The scope and limitations of this novel process in densely substituted substrates are evaluated, and possible competitive reactions and/or stereochemical influences are also described. A mechanism based on a highly ordered chair-like transition state substantiated by a theoretical study is also included.
