22759-33-7Relevant academic research and scientific papers
Exploring the substrate specificity of Cytochrome P450cin
Stok, Jeanette E.,Giang, Peter D.,Wong, Siew Hoon,De Voss, James J.
, (2019/08/02)
Cytochromes P450 are enzymes that catalyse the oxidation of a wide variety of compounds that range from small volatile compounds, such as monoterpenes to larger compounds like steroids. These enzymes can be modified to selectively oxidise substrates of interest, thereby making them attractive for applications in the biotechnology industry. In this study, we screened a small library of terpenes and terpenoid compounds against P450cin and two P450cin mutants, N242A and N242T, that have previously been shown to affect selectivity. Initial screening indicated that P450cin could catalyse the oxidation of most of the monoterpenes tested; however, sesquiterpenes were not substrates for this enzyme or the N242A mutant. Additionally, both P450cin mutants were found to be able to oxidise other bicyclic monoterpenes. For example, the oxidation of (R)- and (S)-camphor by N242T favoured the production of 5-endo-hydroxycamphor (65–77% of the total products, dependent on the enantiomer), which was similar to that previously observed for (R)-camphor with N242A (73%). Selectivity was also observed for both (R)- and (S)-limonene where N242A predominantly produced the cis-limonene 1,2-epoxide (80% of the products following (R)-limonene oxidation) as compared to P450cin (23% of the total products with (R)-limonene). Of the three enzymes screened, only P450cin was observed to catalyse the oxidation of the aromatic terpene p-cymene. All six possible hydroxylation products were generated from an in vivo expression system catalysing the oxidation of p-cymene and were assigned based on 1H NMR and GC-MS fragmentation patterns. Overall, these results have provided the foundation for pursuing new P450cin mutants that can selectively oxidise various monoterpenes for biocatalytic applications.
Oxidation of Vicinal Diols to α-Hydroxy Ketones with H2O2 and a Simple Manganese Catalyst
Mecozzi, Francesco,Dong, Jia Jia,Saisaha, Pattama,Browne, Wesley R.
supporting information, p. 6919 - 6925 (2017/12/26)
α-Hydroxy ketones are valuable synthons in organic chemistry. Here we show that oxidation of vic-diols to α-hydroxy ketones with H2O2 can be achieved with an in situ prepared catalyst based on manganese salts and pyridine-2-carboxylic acid. Furthermore the same catalyst is effective in alkene epoxidation, and it is shown that alkene oxidation with the MnII catalyst and H2O2 followed by Lewis acid ring opening of the epoxide and subsequent oxidation of the alkene to α-hydroxy ketones can be achieved under mild (ambient) conditions.
Multiple monohydroxylation products from rac-camphor by marine fungus Botryosphaeria sp. Isolated from marine alga Bostrychia radicans
De Jesus, Hugo C.R.,Jeller, Alex H.,Debonsi, Hosana M.,Alves, Péricles B.,Porto, André L.M.
, p. 498 - 504 (2017/01/24)
This manuscript describes the biooxidation of rac-camphor using whole cells of marine-derived fungus Botryosphaeria sp. CBMAI 1197. The main biotransformation products of this monoterpene were achieved via a hydroxylation reaction and occurred with 5 days of rac-camphor incubation. Products were identified by means of gas chromatography mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) data. The major hydroxylated products were 6-endo-hydroxycamphor, 6-exo-hydroxycamphor, 5-exo-hydroxycamphor, 5-endo-hydroxycamphor, 3-exo-hydroxycamphor and 8-hydroxycamphor. The 6-exo-hydroxycamphor was obtained through a retro-aldol reaction when 6-endo-hydroxycamphor was maintained in presence of CDCl3; this isomerization was confirmed by 1H NMR and GC-MS data.
In vivo and in vitro hydroxylation of cineole and camphor by cytochromes P450CYP101A1, CYP101B1 and N242A CYP176A1
Stok, Jeanette E.,Hall, Emma A.,Stone, Isobella S.J.,Noble, Margaret C.,Wong, Siew Hoon,Bell, Stephen G.,De Voss, James J.
, p. 52 - 64 (2016/04/06)
Cytochromes P450 (P450s) are valuable enzymes that can generate a range of useful compounds via biocatalytic oxidations that complement traditional synthetic chemistry. In this study three bacterial P450s, P450cam (CYP101A1), CYP101B1 and the m
General and efficient α-oxygenation of carbonyl compounds by TEMPO induced by single-electron-transfer oxidation of their enolates
Dinca, Emanuela,Hartmann, Philip,Smrcek, Jakub,Dix, Ina,Jones, Peter G.,Jahn, Ullrich
supporting information, p. 4461 - 4482 (2012/10/30)
A generally applicable method for the synthesis of protected α-oxygenated carbonyl compounds is reported. It is based on the single-electron-transfer oxidation of easily generated enolates to the corresponding α-carbonyl radicals. Coupling with the stable free radical TEMPO provides α-(piperidinyloxy) ketones, esters, amides, acids or nitriles in moderate-to-excellent yields. Enolate aggregates influence the outcome of the oxygenation reactions significantly. Competitive reactions have been analyzed and conditions for their minimization are presented. Chemoselective reduction of the products led to either N-O bond cleavage to α-hydroxy carbonyl compounds or reduction of the carbonyl functionality tomonoprotected 1,2-diols or O-protected amino alcohols. The oxygenation of enolates proves to be the most general and effective methodology for the synthesis of O-protected α-oxy carbonyl compounds and nitriles A. The scope and limitations of the electron-transfer-induced radical coupling reaction with TEMPO are presented. The reaction pathways are outlined. Methods for the deprotection to α-hydroxy carbonyl compounds B are provided and discussed. Copyright
Reduction of various ketones by red algae
Utsukihara, Takamitsu,Misumi, Osami,Kato, Nakahide,Kuroiwa, Tsuneyoshi,Horiuchi, C. Akira
, p. 1179 - 1185 (2007/10/03)
The reduction of acetophenone derivatives, (+)- and (-)-camphorquinones and steroidal ketones using red algae (Cyanidioschyzon merolae 10D and Cyanidium caldarium) was investigated. It was found that fluoro, chloro and bromo acetophenone derivatives 1a-i were reduced with good enantioselectivity. On the contrary, reduction of methyl and methoxy acetophenone 1j-o showed low enantioselectivity. The reduction followed Prelog's rule, giving the (S)-alcohols in all cases. Moreover, (+)- camphorquinone 5a was reduced to give (-)-3S- exo-hydroxycamphor 5d as the major product with high stereoselectivity in high yield. In addition, it was found that reduction of 5α-androstane-3,17-dione 8a gave the 3α-OH isomer (3α-OH/3β-OH = 76/24) with high stereoselectivity. Overall it was found that C. merolae and C. caldarium were able to reduce various substrates.
A novel synthesis of α-hydroxy- and α,α′- dihydroxyketone from α-iodo and α,α′-diiodo ketone using photoirradiation
Horiuchi, C. Akira,Takeda, Akinori,Chai, Wen,Ohwada, Kishoh,Ji, Shun-Jun,Takahashi, T. Tomoyoshi
, p. 9307 - 9311 (2007/10/03)
A novel reaction of α-iodo ketone (α-iodocycloalkanone, α-iodo-β-alkoxy ester, and α-iodoacyclicketone) with irradiation under a high-pressure mercury lamp gave the corresponding α-hydroxyketone in good yields. In the case of α,α′- diiodo ketone, α,α′-dihydroxyketone which little has been reported until now was obtained. This reaction affords a new, clean and convenient synthetic method for α-hydroxy- and α,α′- dihydroxyketone.
Biotransformation of (+)- and (-)-camphorquinones by plant cultured cells
Chai, Wen,Hamada, Hiroki,Suhara, Jumpei,Akira Horiuchi
, p. 669 - 673 (2007/10/03)
Biotransformation of (+)- and (-)-camphorquinones with suspension plant cultured cells of Nicotiana tabacum and Catharanthus roseus was investigated. It was found that the plant cultured cells of N. tabacum and C. roseus reduce stereoselectively the carbonyl group of (+)- and (-)-camphorquinones to the corresponding α-keto alcohols.
Diastereoselective Hydroxylation of Titanium Enolates with tert-Butylhydroperoxide
Schulz M.,Kluge, R.,Schuessler, M.,Hoffmann, G.
, p. 3175 - 3180 (2007/10/02)
The oxidation of titanium enolates with tert-butylhydroperoxide has been investigated and the main reaction products, the corresponding α-hydroxyketones 7a-f, isolated.The highest diastereoselectivities (>95percent de) were obtained, when titanium enolates of camphor 2d-6d were employed.For comparison, the oxidation of the enolates with dimethyldioxirane is discussed.
