764-32-9Relevant articles and documents
Using Terpene Synthase Plasticity in Catalysis: On the Enzymatic Conversion of Synthetic Farnesyl Diphosphate Analogues
Hou, Anwei,Dickschat, Jeroen S.
, p. 15644 - 15649 (2021/10/04)
Four synthetic farnesyl diphosphate analogues were enzymatically converted with three bacterial sesquiterpene synthases, including β-himachalene synthase (HcS) and (Z)-γ-bisabolene synthase (BbS) from Cryptosporangium arvum, and germacrene A synthase (SmTS6) from Streptomyces mobaraensis. These enzyme reactions not only yielded several previously unknown compounds, showing that this approach opened the door to a new chemical space, but substrates with blocked or altered reactivities also gave interesting insights into the cyclisation mechanisms and the potential to catalyse reactions with different initial cyclisation modes.
AuCl3-Catalyzed Ring-Closing Carbonyl–Olefin Metathesis
Wang, Rui,Chen, Yi,Shu, Mao,Zhao, Wenwen,Tao, Maoling,Du, Chao,Fu, Xiaoya,Li, Ao,Lin, Zhihua
supporting information, p. 1941 - 1946 (2020/02/11)
Compared with the ripeness of olefin metathesis, exploration of the construction of carbon–carbon double bonds through the catalytic carbonyl–olefin metathesis reaction remains stagnant and has received scant attention. Herein, a highly efficient AuCl3-catalyzed intramolecular ring-closing carbonyl–olefin metathesis reaction is described. This method features easily accessible starting materials, simple operation, good functional-group tolerance and short reaction times, and provides the target cyclopentenes, polycycles, benzocarbocycles, and N-heterocycle derivatives in good to excellent yields.
Hydrogenative metathesis of enynes via piano-stool ruthenium carbene complexes formed by alkyne gem-hydrogenation
Peil, Sebastian,Bistoni, Giovanni,Goddard, Richard,Fürstner, Alois
supporting information, p. 18541 - 18553 (2020/11/17)
The only recently discovered gem-hydrogenation of internal alkynes is a fundamentally new transformation, in which both H atoms of dihydrogen are transferred to the same C atom of a triple bond while the other position transforms into a discrete metal carbene complex. [Cp?RuCl]4 is presently the catalyst of choice: the resulting piano-stool ruthenium carbenes can engage a tethered alkene into either cyclopropanation or metathesis, and a prototypical example of such a reactive intermediate with an olefin ligated to the ruthenium center has been isolated and characterized by X-ray diffraction. It is the substitution pattern of the olefin that determines whether metathesis or cyclopropanation takes place: a systematic survey using alkenes of largely different character in combination with a computational study of the mechanism at the local coupled cluster level of theory allowed the preparative results to be sorted and an intuitive model with predictive power to be proposed. This model links the course of the reaction to the polarization of the double bond as well as to the stability of the secondary carbene complex formed, if metathesis were to take place. The first application of "hydrogenative metathesis"to the total synthesis of sinularones E and F concurred with this interpretation and allowed the proposed structure of these marine natural products to be confirmed. During this synthesis, it was found that gem-hydrogenation also provides opportunities for C-H functionalization. Moreover, silylated alkynes are shown to participate well in hydrogenative metathesis, which opens a new entry into valuable allylsilane building blocks. Crystallographic evidence suggests that the polarized [Ru-Cl] bond of the catalyst interacts with the neighboring R3Si group. Since attractive interligand Cl/R3Si contacts had already previously been invoked to explain the outcome of various ruthenium-catalyzed reactions, including trans-hydrosilylation, the experimental confirmation provided herein has implications beyond the present case.
Hydrogenative Cyclopropanation and Hydrogenative Metathesis
Peil, Sebastian,Guthertz, Alexandre,Biberger, Tobias,Fürstner, Alois
supporting information, p. 8851 - 8856 (2019/05/28)
The unusual geminal hydrogenation of a propargyl alcohol derivative with [CpXRuCl] as the catalyst entails formation of pianostool ruthenium carbenes in the first place; these reactive intermediates can be intercepted with tethered alkenes to give either cyclopropanes or cyclic olefins as the result of a formal metathesis event. The course of the reaction is critically dependent on the substitution pattern of the alkene trap.
Evolution of a Polyene Cyclization Cascade for the Total Synthesis of (?)-Cyclosmenospongine
Speck, Klaus,Magauer, Thomas
supporting information, p. 1157 - 1165 (2017/02/05)
We report a full account on the development of a unique cationic polyene cyclization for the total synthesis of the tetracyclic meroterpenoid (?)-cyclosmenospongine. A highly convergent three-component coupling strategy enabled rapid access to individual cyclization precursors that were tested for their reactivity. The successful transformation generates three rings and sets four consecutive stereocenters in a single operation proceeding in a highly efficient manner to give exclusively the trans-decalin framework. In addition, we found that the enol ether geometry and the relative configuration of C3 and C8 are crucial for the success of the polyene cyclization.
Synthesis of (±) debenzoyl analogs of norsampsones as potential anticancer agents
Jadhav, Amol R.,Thombal, Raju S.,Nigam, Preeti,Jadhav, Vrushali H.
supporting information, p. 5235 - 5237 (2015/08/19)
Synthesis of (±) debenzoyl analogs of norsampsones 1 and 2 is reported starting from commercially available 1,3-cyclohexadione in six steps with overall yields of 37% and 36%, respectively. Compounds 1 and 2 were tested for their anticancer activity and showed moderate anticancer activity against HeLa cell lines.
Photocatalytic One-Pot Synthesis of Homoallyl Ketones via a Norrish Type i Reaction of Cyclopentanones
Okada, Megumi,Yamada, Keiichi,Fukuyama, Takahide,Ravelli, Davide,Fagnoni, Maurizio,Ryu, Ilhyong
, p. 9365 - 9369 (2015/09/28)
A photocatalytic synthesis of homoallyl ketones was achieved via a one-pot procedure starting from a Norrish Type I reaction of cyclopentanones, followed by a decatungstate-catalyzed hydroacylation of electron-deficient olefins by the resulting 4-pentenals. The site-selective formyl H-abstraction in the second step can be explained by radical polar effects in the transition state.
DIHYDROOROTIC ACID DEHYDROGENASE INHIBITOR
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Paragraph 0293; 0296; 0309, (2015/04/15)
The present invention provides a novel dihydroorotic acid dehydrogenase inhibitor which is applicable to various diseases. When used as an active ingredient, a compound represented by formula (I): (wherein X represents a halogen atom, R1 represents a hydrogen atom, R2 represents an alkyl group containing 1 to 7 carbon atoms, R3 represents -CHO, and R4 represents -CH2-CH=C(CH3)-R0 (wherein R0 represents an alkyl group containing 1 to 12 carbon atoms which may have a substituent on the terminal carbon and/or on a non-terminal carbon, etc.)), an optical isomer thereof or a pharmaceutically acceptable salt thereof has a high inhibitory effect on dihydroorotic acid dehydrogenase and can be used as an immunosuppressive agent, a therapeutic agent for rheumatism, an anticancer agent, a therapeutic agent for graft rejection, an antiviral agent, an anti-H. pylori agent, a therapeutic agent for diabetes or the like.
Stereospecific nickel-catalyzed cross-coupling reactions of alkyl grignard reagents and identification of selective anti-breast-cancer agents
Yonova, Ivelina M.,Johnson, A. George,Osborne, Charlotte A.,Moore, Curtis E.,Morrissette, Naomi S.,Jarvo, Elizabeth R.
supporting information, p. 2422 - 2427 (2014/03/21)
Alkyl Grignard reagents that contain β-hydrogen atoms were used in a stereospecific nickel-catalyzed cross-coupling reaction to form C(sp 3)-C(sp3) bonds. Aryl Grignard reagents were also utilized to synthesize 1,1-diarylalkanes. Sev
Analysis of enantiofacial selective epoxidation catalyzed by flavin-containing monooxygenase Lsd18 involved in ionophore polyether lasalocid biosynthesis
Suzuki, Gaku,Minami, Atsushi,Shimaya, Mayu,Kodama, Takeshi,Morimoto, Yoshiki,Oguri, Hiroki,Oikawa, Hideaki
supporting information, p. 1779 - 1781 (2015/02/19)
Enzymatic epoxidation represents a key biosynthetic transformation in the construction of polyether skeletons. A single flavin-containing monooxygenase, Lsd18, is involved in ionophore polyether lasalocid biosynthesis and participates in the enantioselective epoxidations of the diene precursor. Biotransformation studies utilizing structurally simplified monoolefin analogs with different substitution patterns revealed important structural requirements for the enantiofacial selectivity of Lsd18-catalyzed epoxidations. These results enabled us to propose a substrate binding model of Lsd18, which was applied to the biosynthesis of other polyethers.
