7367-82-0Relevant articles and documents
A One-Pot Synthesis of α,β-Unsaturated Esters From Esters
Hong, Chang Whee,Lee, Yong Jin,An, Duk Keun
, p. 1121 - 1125 (2021/06/01)
A convenient method for reductive Horner–Wadsworth–Emmons (HWE) olefination is described. The E-selective HWE homologation of various esters to α,β-unsaturated esters was readily achieved and gave the desired products in good-to-moderate yields under mild conditions. The one-pot reaction proceeds through an in situ generated aldehyde, formed via the partial reduction of an ester with lithium diisobutyl-t-butoxyaluminum hydride. The formation of cyclized metal acetal and subsequent decompose to the aldehyde for the olefination was found to be a crucial step in this C2-carbon homologation protocol.
Synthesis and Biological Evaluation of Hoshionolactam-Based Compounds
Elizebath, Drishya,Jachak, Gorakhnath R.,Reddy, D. Srinivasa,Shanmugam, Dhanasekaran,Shukla, Anurag
, p. 2212 - 2218 (2021/07/22)
In search of novel antitrypanosomal agents based on hoshinolactam (IC50=3.9 nM), we disclose the synthesis and biological evaluations of 14 different analogues of the natural product using combinations of different acids and lactams. Antitrypanosomal activity assays revealed that the synthesized analogues were less potent than the parent natural product.
Phosphorus-recycling wittig reaction: Design and facile synthesis of a fluorous phosphine and its reusable process in the wittig reaction
Yamamoto, Yuki,Kawaguchi, Shin-Ichi,Nishimura, Misaki,Sato, Yuki,Shimada, Yoshihisa,Tabuchi, Akihiro,Nomoto, Akihiro,Ogawa, Akiya
, p. 14684 - 14696 (2020/11/30)
This study shows that phosphorus sources can be recycled using the appropriate fluorous phosphine in the Wittig reaction. The designed fluorous phosphine, which has an ethylene spacer between its phosphorus atom and the perfluoroalkyl group, was synthesized from air-stable phosphine reagents. The synthesized phosphine can be used for the Wittig reaction process to obtain various alkenes in adequate yields and stereoselectivity. The concomitantly formed fluorous phosphine oxide was extracted from the reaction mixture using a fluorous biphasic system. The fluorous phosphine was regenerated by reducing the fluorous phosphine oxide with diisobutylaluminum hydride. Finally, a series of gram scale phosphorus recycling processes were performed, which included the Wittig reaction, separation, reduction, and reuse.
CuBr2-catalyzed diastereoselective allylation: Total synthesis of decytospolides A and B and their C6-epimers
Choudhury, Utkal Mani,Mallampudi, N. Arjunreddy,Mohapatra, Debendra K.,Padhi, Birakishore,Reddy, G. Sudhakar
, p. 2685 - 2695 (2020/04/17)
An efficient CuBr2-catalyzed diastereoselective allylation of a cyclic hemiacetal with allyltrimethylsilane as a nucleophile has been developed. The protocol offers a cost effective, protecting group tolerant, and operationally simple approach to 2,6-trans-disubstituted tetrahydropyran with excellent diastereoselectivity. Furthermore, the application of this methodology has been demonstrated in the total synthesis of decytospolides A and B and their C6-epimers.
Stereoselective Synthesis of C1–C7 and C6–C22 Fragments of Phostriecin, Goniothalamines, and Their Analogues
Purushotham Reddy,Vasudeva Reddy,Sabitha, Gowravaram
, p. 4389 - 4399 (2018/09/11)
The stereoselective synthesis of two fragments (C1–C7 and C6–C22) of the anti-tumor agent phostriecin has been achieved. The chiral hydroxy-vinyl-δ-lactone building block (fragment C1–C7) was subsequently utilized for the synthesis of 5-hydroxygoniothalamin, 5-acetoxygoniothalamin, and their derivatives.
Synthesis of α,β-unsaturated aldehydes as potential substrates for bacterial luciferases
Brodl, Eveline,Ivkovic, Jakov,Tabib, Chaitanya R.,Breinbauer, Rolf,Macheroux, Peter
, p. 1487 - 1495 (2017/02/18)
Bacterial luciferase catalyzes the monooxygenation of long-chain aldehydes such as tetradecanal to the corresponding acid accompanied by light emission with a maximum at 490?nm. In this study even numbered aldehydes with eight, ten, twelve and fourteen carbon atoms were compared with analogs having a double bond at the α,β-position. These α,β-unsaturated aldehydes were synthesized in three steps and were examined as potential substrates in vitro. The luciferase of Photobacterium leiognathi was found to convert these analogs and showed a reduced but significant bioluminescence activity compared to tetradecanal. This study showed the trend that aldehydes, both saturated and unsaturated, with longer chain lengths had higher activity in terms of bioluminescence than shorter chain lengths. The maximal light intensity of (E)-tetradec-2-enal was approximately half with luciferase of P. leiognathi, compared to tetradecanal. Luciferases of Vibrio harveyi and Aliivibrio fisheri accepted these newly synthesized substrates but light emission dropped drastically compared to saturated aldehydes. The onset and the decay rate of bioluminescence were much slower, when using unsaturated substrates, indicating a kinetic effect. As a result the duration of the light emission is doubled. These results suggest that the substrate scope of bacterial luciferases is broader than previously reported.
Asymmetric Total Syntheses of Two Possible Diastereomers of Gliomasolide e and Its Structural Elucidation
Reddy, Ramidi Gopal,Venkateshwarlu, Ravula,Ramakrishna, Kallaganti V. S.,Yadav, Jhillu S.,Mohapatra, Debendra K.
, p. 1053 - 1063 (2018/06/18)
The first total syntheses of two possible diastereomers of gliomasolide E, a 14-membered macrolides isolated from the marine sponge Phakellia fusca Thiele, which was collected from the South China Sea, is reported. Highlights of the synthesis include macrolactonization through intramolecular Horner-Wadsworth-Emmons olefination, Yamaguchi-Hirao alkynylation, and base-induced elimination reactions for propargyl alcohol synthesis as the key reactions. Detailed comparison of their 1H and 13C NMR (1D and 2D NMR data) and specific rotation with those of the natural product revealed that the absolute stereochemistry of gliomasolide E should be (2E,5R,7R,9R,13R).
Selective Hydrogenation of Functionalized Alkynes to (E)-Alkenes, Using Ordered Alloys as Catalysts
Furukawa, Shinya,Komatsu, Takayuki
, p. 2121 - 2125 (2016/03/15)
Intermetallic Pd3Pb acts as a highly selective alkyne semihydrogenation catalyst that is greatly superior to the conventional Lindlar catalyst. Density functional theory (DFT) calculations demonstrate an ideal adsorption property of Pd3Pb, where the surface holds alkynes while releasing alkenes. A tandem catalytic system that is comprised of Pd3Pb/SiO2 for alkyne semihydrogenation and RhSb/SiO2 for alkene isomerization allows one-pot (E)-alkene synthesis from a functionalized alkyne, which is the first success using heterogeneous catalysts. A variety of functionalized alkynes with aldehyde, ketone, carboxylic acid, and ester moieties are hydrogenated into the corresponding (E)-alkene in good to excellent yields under 1 atm H2 at room temperature.
Oxidative carbon-carbon bond cleavage is a key step in spiroacetal biosynthesis in the fruit fly Bactrocera cacuminata
Singh, Arti A.,Rowley, Jessica A.,Schwartz, Brett D.,Kitching, William,De Voss, James J.
, p. 7799 - 7821 (2015/03/18)
The early steps of spiroacetal biosynthesis in the fruit fly Bactrocera cacuminata (Solanum fly) have been investigated using a series of deuterium-labeled, oxygenated fatty acid like compounds. These potential spiroacetal precursors were administered to male flies, and their volatile emissions were analyzed for specific deuterium incorporation by GC/MS. This has allowed the order of early oxidative events in the biosynthetic pathway to be determined. Together with the already well-established later steps, the results of these in vivo investigations have allowed essentially the complete delineation of the spiroacetal biosynthetic pathway, beginning from products of primary metabolism. A fatty acid equivalent undergoes a series of enzyme-mediated oxidations leading to a trioxygenated fatty acid like species that includes a vicinal diol. This moiety then undergoes enzyme-mediated oxidative carbon-carbon bond cleavage as the key step to generate the C9 unit of the final spiroacetal. This is the first time such an oxidative transformation has been reported in insects. A final hydroxylation step is followed by spontaneous spiro-cyclization. This distinct pathway adds further to the complexity and diversity of biosynthetic pathways to spiroacetals.
Microwave-assisted convenient synthesis of α,β-unsaturated esters and ketones via aldol-adduct elimination
Suman, Pathi,Nageswara Rao, Rayala,China Raju, Bhimapaka
, p. 1548 - 1559 (2013/09/02)
Various fluorinated 3-oxo ester/1,3-diketones were reacted with carbonyl compounds, in presence of piperidine and under microwave irradiation, to afford (E)-α,β-unsaturated esters and ketones in good yields. The systematic study reveals that the reaction proceeded through the formation of aldol adduct. The method provides a new and simple way for C,C bond formations. Copyright
