52590-98-4Relevant academic research and scientific papers
Calcium binding and transport by coenzyme Q
Bogeski, Ivan,Gulaboski, Rubin,Kappl, Reinhard,Mirceski, Valentin,Stefova, Marina,Petreska, Jasmina,Hoth, Markus
, p. 9293 - 9303 (2011)
Coenzyme Q10 (CoQ10) is one of the essential components of the mitochondrial electron-transport chain (ETC) with the primary function to transfer electrons along and protons across the inner mitochondrial membrane (IMM). The concomitant proton gradient ac
Type II NADH dehydrogenase of the respiratory chain of Plasmodium falciparum and its inhibitors
Dong, Carolyn K.,Patel, Vishal,Yang, Jimmy C.,Dvorin, Jeffrey D.,Duraisingh, Manoj T.,Clardy, Jon,Wirth, Dyann F.
supporting information; experimental part, p. 972 - 975 (2009/08/15)
Plasmodium falciparum NDH2 (pfNDH2) is a non-proton pumping, rotenone-insensitive alternative enzyme to the multi-subunit NADH:ubiquinone oxidoreductases (Complex I) of many other eukaryotes. Recombinantly expressed pfNDH2 prefers coenzyme CoQ0 as an acceptor substrate, and can also use the artificial electron acceptors, menadione and dichlorophenol-indophenol (DCIP). Previously characterized NDH2 inhibitors, dibenziodolium chloride (DPI), diphenyliodonium chloride (IDP), and 1-hydroxy-2-dodecyl-4(1H)quinolone (HDQ) do not inhibit pfNDH2 activity. Here, we provide evidence that HDQ likely targets another P. falciparum mitochondrial enzyme, dihydroorotate dehydrogenase (pfDHOD), which is essential for de novo pyrimidine biosynthesis.
Synthetic studies on coenzyme Q10: Part 2 - A efficient and improved synthesis of coenzyme Q10 via the C5 + C 45 approach
Dai, Hui-Fang,Chen, Fen-Er,Yu, Xiong-Jie
, p. 1317 - 1321 (2007/10/03)
An improved route to coenzyme Q10 (1) starting from commercially available coenzyme Q1 is described. The key steps in this synthesis are the SeO2-mediated oxidation of the protected isoprenylhydroquinone 3 into the (E)-allyl alcohol 5 without the formation of undesired stereoisomer and the one-pot reductive elimination of the phenylsulfonyl and dibenzyl groups in 7 by using naphthalenyllithium.
The surprisingly high reactivity of phenoxyl radicals
Foti,Ingold,Lusztyk
, p. 9440 - 9447 (2007/10/02)
Rate constants have been measured in nonaqueous media for hydrogen atom abstraction by the phenoxyl radical from some biologically important phenols and related compounds. Although the thermochemistry for these reactions must be very similar to the thermochemistry for H atom abstraction from the same substrate by a peroxyl radical, the phenoxyl rate constants, k5, are ca. 100-300 times greater than the (already well-known) peroxyl rate constants, k1. For example, with α-tocopherol in benzene/di-tert-butyl peroxide (1:3, v/v) k5293K = 1.1 × 109 M-1 s-1 vs k1303K = 3.2 × 106 M-1 s-1 in a similar nonpolar medium, and with ubiquinol-10 in the same solvent mixture k5293k = 8.4 × 107 M-1 s-1, while the corresponding value for k1 is 3.5 × 105 M-1 s-1. The greater reactivity of the phenoxyl radical has been traced to the fact that the Arrhenius preexponential factors are much larger than for the corresponding peroxyl radical reactions, i.e., A5 ～ 102A1. For example, with α-naphthol log(A5/M-1 s-1) = 8.9 and E5 = 2.2 kcal/mol vs log(A1/M-1 s-1) = 6.4 and E1 = 1.7 kcal/mol. The preexponential factors for H-atom donors more reactive than α-naphthol are even greater; for example, with α-tocopherol in CH3CN/di-tert-butyl peroxide (1:2, v/v) log(A5/M-1 s-1) = 10.0 and E5 = 2.0 kcal/mol, and with ubiquinol-0 in benzene/di-tert-butyl peroxide (1:3, v/v) log(A5/M-1 s-1) = 10.5 and E5 = 3.5 kcal/mol. The role that intermediate hydrogen-bonded complexes between the reacting radical and the phenolic hydrogen donor may play in these reactions is discussed, and it is pointed out that our results are likely to be relevant to in vivo radical chemistry.
Quinones. Part 2. General Synthetic Routes to Quinone Derivatives with Modified Polyprenyl Side Chains and the Inhibitory Effects of these Quinones on the Generation of the Slow Reacting Substance of Anaphylaxis (SRS-A)
Terao, Shinji,Shiraishi, Mitsuru,Kato, Kaneyoshi,Ohkawa, Shigenori,Ashida, Yasuko,Maki, Yoshitaka
, p. 2909 - 2920 (2007/10/02)
General synthetic routes to quinone acids (8), quinone amides (9), quinone alcohols (10), and quinone methylketones (11) with polyprenyl side chains, in which allylic alcohols (3) are employed as the key intermediates, are described.The Claisen rearrangements and the Carrol reactions of the allylic alcohols (3) with ethyl orthoacetate and diketen produced the ethyl esters (4) and the methylketones (5), respectively.Quinone products (8), (10), and (11) were recovered by oxidative demethylation of hydroquinone dimethyl ethers (4), (5), and (7) or by acid hydrolysis of hydroquinone bis(methoxymethyl) ethers (4) and (5) followed by ferric chloride oxidation.Amidation of quinone acids (8) led to the formation of quinone amides (9).Inhibitory effects of these quinone derivatives on the generation of the slow reacting substance of anaphylaxis (SRS-A) in the lungs of sensitised guinea pigs are evaluated.
Allylation of Quinones with Allyltin Reagents
Naruta, Yoshinori
, p. 3774 - 3783 (2007/10/02)
Lewis acid (BF3) catalyzed allylation of quinones with allyl- (2a), 2-methyl-2-propenyl- (2b), trans-2-butenyl- (2c,d), 3-methyl-2-butenyl- (2e,f), and trans-cinnamyltrialkyltin (2g) gives the corresponding allylhydroquinones with high regioselectivity.Vitamin K2(5) (7) and coenzyme Q1 (9) were prepared in yields of 78 and 75percent, respectively.These reactions appear to proceed through allylquinol intermediates which undergo rearrangement under the influence of BF3.The success of this synthesis of vitamin K2(5) and coenzyme Q1 depends on the fact that the reaction of 3-methyl-2-butenyltin with quinones occurs at the α carbon of the allylic system.
