- Alternative routes to the acylphloroglucinol rhodomyrtone
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Two novel routes to the acylphloroglucinol rhodomyrtone (1) which has antibiotic properties are presented. In the first route an ortho-quinone methide, generated from dioxaborinine 23, is reacted with syncarpic acid (10) leading to xanthenedione 25. Cleavage of the methyl ether functions led to the known rhodomyrtone precursor 16. In the second route the bis-ester derivative 28 of trihydroxybenzaldehyde 26 is condensed with syncarpic acid (10) to give tricyclic hemiacetal 29. Acetalization and cuprate addition to the enone function led to bis-ester 32 which gave rhodomyrtone (1) by TiCl4-induced regioselective Fries rearrangement.
- Morkunas, Marius,Maier, Martin E.
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Read Online
- On the thermal degradation of anthocyanidins: Cyanidin
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Cyanidin was studied by direct pH jumps (from equilibrated solutions at very low pH values to higher pH values) and reverse pH jumps (from equilibrated or not equilibrated solutions at higher pH values to very low ones). The kinetic steps of the direct and reverse pH jumps were followed by stopped flow, absorption spectroscopy and HPLC, at different timescales. The pH dependent rate constant of the slower kinetic process to reach the equilibrium follows a bell shaped curve as described for many synthetic flavylium compounds. Unlike anthocyanins, it was proved that there is no pH dependent reversibility in the system, since the chalcone suffers an irreversible degradation process. The mathematical expression to describe the bell shaped behaviour was deduced. These results contribute to explain why in plants glycosylation is crucial for the stabilization of the anthocyanins.
- Cabrita, Luis,Petrov, Vesselin,Pina, Fernando
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Read Online
- Anti-oxidant activity of flavonols: Reactivity with potassium superoxide in the heterogeneous phase
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Oxidation of flavonols by potassium superoxide (KO2) in heterogeneous aprotic media yields acids and aldehydes by opening of ring C, if the latter contains an ethylenic double bond substituted by an OH group. A mechanism is proposed for this reaction. Other flavonoids like flavones, flavans and flavanones induce only the disproportionation of superoxide anion, without undergoing further oxidation; these flavonoids are therefore anti-oxidants of particular interest.
- Tournaire,Hocquaux,Beck,Oliveros,Maurette
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Read Online
- Discovery of Anti-TNBC Agents Targeting PTP1B: Total Synthesis, Structure-Activity Relationship, in Vitro and in Vivo Investigations of Jamunones
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Twenty-three natural jamunone analogues along with a series of jamunone-based derivatives were synthesized and evaluated for their inhibitory effects against breast cancer (BC) MDA-MB-231 and MCF-7 cells. The preliminary structure-activity relationship revealed that the length of aliphatic side chain and free phenolic hydroxyl group at the scaffold played a vital role in anti-BC activities and the methyl group on chromanone affected the selectivity of molecules against MDA-MB-231 and MCF-7 cells. Among them, jamunone M (JM) was screened as the most effective anti-triple-negative breast cancer (anti-TNBC) candidate with a high selectivity against BC cells over normal human cells. Mechanistic investigations indicated that JM could induce mitochondria-mediated apoptosis and cause G0/G1 phase arrest in BC cells. Furthermore, JM significantly restrained tumor growth in MDA-MB-231 xenograft mice without apparent toxicity. Interestingly, JM could downregulate phosphatidylinositide 3-kinase (PI3K)/Akt pathway by suppressing protein-tyrosine phosphatase 1B (PTP1B) expression. These findings revealed the potential of JM as an appealing therapeutic drug candidate for TNBC.
- Hu, Caijuan,Li, Guoxun,Mu, Yu,Wu, Wenxi,Cao, Bixuan,Wang, Zixuan,Yu, Hainan,Guan, Peipei,Han, Li,Li, Liya,Huang, Xueshi
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supporting information
p. 6008 - 6020
(2021/05/06)
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- Synthetic method of pilosin B and intermediate pseudomonophenols thereof
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The invention discloses a method for synthesizing pilosin B and intermediate pseudomonophenols thereof. The synthesis method of the pseudo-sheep equol comprises the step E. Step F and Step g. The synthetic method of the pilosin B provided by the invention is prepared by the following steps H, step J, preparation of the pseudomonophenols synthesized by the above method, and preparation of the pseudomonophenols synthesized by the method in step I. In step E, the novel amino protecting reagent with good reaction with the phenolic hydroxyl group is used as a protecting reagent, the phenol hydroxyl group of each intermediate in the intermediate molecule fragment a synthesis process is selectively protected, the reagent types are reduced and the use of toxic reagents such as benzyl chloride and the like is avoided.
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Paragraph 0040; 0066
(2021/11/26)
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- Biomimetic total syntheses of baefrutones A-D, baeckenon B, and frutescones A, D-F
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Biomimetic total syntheses of baefrutones A-D (1-4), baeckenon B (5), and frutescones A, D-F (6-9), isolated from the leaves of Baeckea frutescens, were achieved in 9, 8, and 5 steps, respectively, in moderate to good yields (72-83%). The synthetic routes feature the Michael addition, oxidative [4 + 2] cycloaddition, and water-promoted Diels-Alder click reactions as the key steps. This study helped gain thorough mechanistic insights into the biosynthetic origins and provided a facile approach for the construction of a library of natural tasmanone-based meroterpenoid analogues. Moreover, compounds 1-9 show potent inhibitory effects against S. paratyphi and/or C. albicans with MIC values of 3.125-25 μg mL-1, and they could be promising lead molecules for the design of new antibiotic agents.
- Dong, Ying-Ying,Hou, Ji-Qin,Peng, Qiu-Shi,Wang, Hao,Yu, Jiang-Hong,Zhang, Bao-Bao,Zhao, Heng
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supporting information
p. 1135 - 1139
(2020/02/22)
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- Synthesis and biological evaluation of BMS-986120 and its deuterated derivatives as PAR4 antagonists
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BMS-986120 is a PAR4 antagonist that is being investigated as an antiplatelet agent in phase I clinical trial. An improved synthesis of BMS-986120 has been developed. Based on the novel synthetic approach to BMS-986120, a series of deuterated derivatives of BMS-986120 have been synthesized and biologically evaluated to search for more potent antiplatelet agents. The in vitro antiplatelet assay by turbidimetry demonstrated that PC-2 and PC-6 had IC50 values of 6.30 nM and 6.97 nM, respectively, versus BMS-986120 with an IC50 of 7.80 nM. The result of in vitro metabolic stability study showed that all of the deuterated compounds had similar half-life (T1/2) and intrinsic clearance (Clint) in comparison with BMS-986120. Further probing the metabolic profile of BMS-986120 is worth being conducted.
- Chen, Panpan,Ren, Shenhong,Song, Hangyu,Chen, Cai,Chen, Fangjun,Xu, Qinglong,Kong, Yi,Sun, Hongbin
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p. 116 - 124
(2018/11/30)
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- Novel diphenylmethyl compounds having mycobacterium tuberculosis inhibitory activity
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The invention relates to novel diphenylmethyl derivatives having mycobacterium tuberculosis inhibitory activity and a preparation method thereof and particularly relates novel diphenylmethyl derivatives having activity for inhibiting replicative and non-replicating mycobacterium tuberculosis and a preparation method thereof. In particular, the invention relates to compounds shown in the formula (I) or all possible isomers, prodrugs, pharmaceutically acceptable salts, solvates or hydrates thereof, wherein the variables are as described in the specification. The invention also relates to the preparation method of the compounds and their pharmaceutical compositions and a use of the compounds in preparation of drugs for treating mycobacterium tuberculosis infection-caused diseases.
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Paragraph 0270-0273
(2019/02/13)
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- Derivatives of Natural Product Agrimophol as Disruptors of Intrabacterial pH Homeostasis in Mycobacterium tuberculosis
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This article reports the rational medicinal chemistry of a natural product, agrimophol (1), as a new disruptor of intrabacterial pH (pHIB) homeostasis in Mycobacterium tuberculosis (Mtb). Through the systematic investigation of the structure-activity relationship of 1, scaffold-hopping of the diphenylmethane scaffold, pharmacophore displacement strategies, and studies of the structure-metabolism relationship, a new derivative 5a was achieved. Compound 5a showed 100-fold increased potency in the ability to reduce pHIB to pH 6.0 and similarly improved mycobactericidal activity compared with 1 against both Mycobacterium bovis-BCG and Mtb. Compound 5a possessed improved metabolic stability in human liver microsomes and hepatocytes, lower cytotoxicity, higher selectivity index, and similar pKa value to natural 1. This study introduces a novel scaffold to an old drug, resulting in improved mycobactericidal activity through decreasing pHIB, and may contribute to the critical search for new agents to overcome drug resistance and persistence in the treatment of tuberculosis.
- Wu, Jie,Mu, Ran,Sun, Mingna,Zhao, Nan,Pan, Miaomiao,Li, Hongshuang,Dong, Yi,Sun, Zhaogang,Bai, Jie,Hu, Minwan,Nathan, Carl F.,Javid, Babak,Liu, Gang
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p. 1087 - 1104
(2019/05/22)
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- Deuterated imidazole and thiadiazole derivatives and their medical use (by machine translation)
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The invention of formula (I) indicated by the deuterated imidazole and thiadiazole derivative, or its pharmaceutically acceptable salt or esters or solvates. The compounds of this invention can be used for preparing the prevention or treatment of the thromboembolism drug. (by machine translation)
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Paragraph 0093-0096
(2019/10/07)
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- Antifungal agents: Design, synthesis, antifungal activity and molecular docking of phloroglucinol derivatives
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Pseudoaspidinol is a phloroglucinol derivative with Antifungal activity and is a major active component of Dryopteris fragrans. In our previous work, we studied the total synthesis of pseudoaspidinol belonging to a phloroglucinol derivative and investigated its antifungal activity as well as its intermediates. However, the results showed these compounds have low antifungal activity. In this study, in order to increase antifungal activities of phloroglucinol derivatives, we introduced antifungal pharmacophore allylamine into the methylphloroglucinol. Meanwhile, we remained C1–C4 acyl group in C-6 position of methylphloroglucinol using pseudoaspidinol as the lead compound to obtain novel phloroglucinol derivatives, synthesized 17 compounds, and evaluated antifungal activities on Trichophyton rubrum and Trichophyton mentagrophytes in vitro. Molecular docking verified their ability to combine the protein binding site. The results indicated that most of the compounds had strong antifungal activity, in which compound 17 were found to be the most active on Trichophyton rubrum with Minimum Inhibitory Concentration (MIC) of 3.05 μg/mL and of Trichophyton mentagrophytes with MIC of 5.13 μg/mL. Docking results showed that compounds had a nice combination with the protein binding site. These researches could lay the foundation for developing antifungal agents of clinical value.
- Teng, Xingxing,Wang, Yuanyuan,Gu, Jinhua,Shi, Peiqi,Shen, Zhibin,Ye, Lianbao
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- A natural product yellow filicic acid BB of full-synthesis method
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The invention relates to a natural product yellow filicic acid BB of full-synthesis method, which belongs to the technical field of organic chemistry. The invention from the economic and easy to synthesize the phloroglucinol proceed double-acylated phloroglucinol, then after iodine methane-to-carbon double methylation, removing monomolecular acyl got the midbody 3; to phloroglucinol as raw materials, acetate acylation to obtain the aldehyde phloroglucinol, reduction of the aldehyde is methyl, then acylated to obtain intermediate 6; the two fragments obtained through the Eschenmoser's salt combined yellow filicic acid BB. In the method 42% overall yield of yellow filicic acid improves the BB fully synthetic yield, raw material economy are easy, simple operation, high yield, and suitable for production, may be its biological activity study provide a large number of raw materials.
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Paragraph 0009; 0022
(2019/01/08)
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- Total synthetic method of natural product pseudoaspidinol
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The invention relates to a total synthetic method of a natural product pseudoaspidinol, belonging to the technical field of organic chemistry. The method comprises the steps of carrying out Vilsmeier-Haaucf reaction on economic and easily-available phloroglucinol dehydrate so as to obtain aldehyde-base phloroglucinol, carrying out Clemmensen reduction so as to obtain methyl phloroglucinol, carrying out Friedel-Crafts acylation so as to obtain lysine butyrylation methyl phloroglucinol, carrying out selective protection through ester groups, and carrying out methylation and deprotection, so as to obtain pseudoaspidinol. The total synthetic method has the beneficial effects that the total synthesis yield of pseudoaspidinol is increased at the total yield of 51%, the raw materials are economicand easily available, the operation is simple, the yield is relatively high, and a large number of raw materials are provided for the biological activity research of pseudoaspidinol.
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Paragraph 0016
(2019/01/07)
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- Efficient synthesis of rottlerin and its two subunits
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Rottlerin, a natural product isolated from Mallotus philippensis, is associated with a range of biological activities. Its chemical structure is featured by two different substituted phloroglucinol units linked by a methylene group. In this study, we accomplished a total synthesis of rottlerin using phenol-aldehyde condensation as the key reaction. By our method, gram-scale preparation of the two structural subunits was achieved, and rottlerin was obtained in a longest eight linear step with 20% overall yield. Our study provides a practical solution for obtaining the sample of rottlerin in an efficient way.
- Li, Yangfeng,Yu, Biao,Wang, Renxiao
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supporting information
p. 1856 - 1859
(2016/04/19)
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- On the difference in decomposition of taxifolin and luteolin vs. fisetin and quercetin in aqueous media
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Abstract: The decomposition of flavonols quercetin and fisetin, flavone luteolin and flavanone taxifolin was studied in slightly alkaline solution under ambient conditions. The study was based on spectrophotometry and high-pressure liquid chromatography. Products formed by atmospheric oxygen oxidation and hydrolysis were identified by HPLC–DAD and HPLC–ESI-MS/MS. Only small differences in the chemical structure of flavonoids resulted in extremely variable oxidation pathways and products. Oxidation of flavonols led to the formation of both a benzofuranone derivative and several open structures. On the contrary, the benzofuranone derivative was not found as a product of taxifolin and luteolin oxidative decomposition. These compounds were oxidized to their hydroxylated derivatives and typical open structures. Quercetin was not identified as a possible oxidation product of taxifolin. Graphical Abstract: [Figure not available: see fulltext.]
- Sokolová, Romana,Rame?ová, ?árka,Kocábová, Jana,Kolivo?ka, Viliam,Degano, Ilaria,Pitzalis, Emanuela
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p. 1375 - 1383
(2016/08/12)
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- A comprehensive investigation of guaiacyl-pyranoanthocyanin synthesis by one-/two-dimensional NMR and UPLC-DAD-ESI-MSn
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In red and rosé wines, the grape anthocyanins are progressively converted to more stable pigments, including phenylpyranoanthocyanins. One-/two-dimensional NMR and UPLC-DAD-ESI-MSn measurements were used to monitor the synthesis of guaiacylpyranomalvidin 3-O-glucoside from malvidin 3-O-glucoside and vinylguaiacol in model solutions and identify the products formed during the reaction. The highest conversion rates (30%, determined by 1H qNMR) were obtained with a small excess of vinylguaiacol in methanol/water (70/30) at pH 3 and 35 °C. Two reaction pathways competed with the formation of guaiacylpyranomalvidin 3-O-glucoside. The first one only concerns malvidin 3-O-glucoside and consists in C-ring cleavage with formation of malvone and smaller molecular weight breakdown products. This pathway is favored at higher pH and incubation temperature. At lower pH values or in the presence of large vinylguaiacol excess, faster consumption of malvidin 3-O-glucoside resulted from the formation of more complex pyranoanthocyanins substituted by vinylguaiacol oligomers.
- Vallverdú-Queralt, Anna,Meudec, Emmanuelle,Ferreira-Lima, Nayla,Sommerer, Nicolas,Dangles, Olivier,Cheynier, Véronique,Guernevé, Christine Le
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p. 902 - 910
(2016/01/25)
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- Tandem Chloropalladation/Cyclization and Dearomative Cyclization toward Functionalized Tricyclic Bridged [3.2.1] Skeleton Compounds
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A palladium-catalyzed tandem reaction is reported that involves chloropalladation/cyclization and dearomative cyclization to construct a tricyclic bridged [3.2.1] carbocyclic-skeleton and oxa- and aza-skeletons. In this domino process, a level of ring strain and other competitive reactions, i.e., protonolysis, β-hydride elimination, and chlorination of the C-Pd bond, were suppressed to the lowest level under mild reaction conditions.
- Dong, Yi,Du, Nana,Li, Xueyuan,Zheng, Litao,Liu, Gang
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supporting information
p. 4110 - 4113
(2015/09/01)
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- A short biomimetic synthesis of the meroterpenoids guajadial and psidial A
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The biosynthesis of the meroterpenoid guajadial was previously hypothesized to occur via a hetero-Diels-Alder reaction between caryophyllene and an o-quinone methide. This hypothesis has been verified via the biomimetic synthesis of guajadial and psidial A in an aqueous three-component coupling reaction, between caryophyllene, benzaldehyde, and diformylphloroglucinol.
- Lawrence, Andrew L.,Adlington, Robert M.,Baldwin, Jack E.,Lee, Victor,Kershaw, Jessica A.,Thompson, Amber L.
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supporting information; experimental part
p. 1676 - 1679
(2010/10/19)
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- Anthocyanin stability and recovery: Implications for the analysis of clinical and experimental samples
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The proportion of ingested anthocyanins to reach the systemic circulation is reported to be a small percentage of their ingested dose. This may be due to physiochemical degradation in vivo or following routine sample treatment. Therefore, this study aimed
- Woodward, Gary,Kroon, Paul,Cassidy, Aedin,Kay, Colin
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experimental part
p. 5271 - 5278
(2010/06/11)
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- Efficient total synthesis of 5-methoxypsoralen
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A rapid and efficient synthesis of 5-methoxypsoralen, furocoumarin commonly used in dermatology for the treatment by PUVA therapy of skin diseases, is described using cheap and easily available starting materials. An alternative method to synthesize 7-(2-oxoethoxy)coumarin, the key step to generate the furan ring, is suggested. Georg Thieme Verlag Stuttgart.
- Roux, Delphine,Makki, Safwat,Bévalot, Fran?oise,Humbert, Philippe
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p. 129 - 130
(2008/03/13)
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- Biomimetic synthesis, antimicrobial, antileishmanial and antimalarial activities of euglobals and their analogues
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In the present communication, naturally occurring phloroglucinol- monoterpene adducts, euglobals G1-G4 (3b/a and 4a/b) and 16 new analogues (13a/b-18a/b and 19-22) were synthesized by biomimetic approach. These synthetic compounds differ from natural euglobals in the nature of monoterpene and acyl functionality. All of these compounds were evaluated for their antibacterial, antifungal, antileishmanial and antimalarial activities. Analogue 17b possessed good antibacterial activity against methicillin-resistant Staphylococcus aureus, while analogues 19-22 possessed potent antifungal activity against Candida glabrata with IC50s ranging from 1.5 to 2.5 μg/mL. Euglobals along with all synthesized analogues exhibited antileishmanial activity. Amongst these, euglobal G2 (3a), G3 (4a) and analogues 13a and 14a showed potent antileishmanial activity with IC50s ranging from 2.8 to 3.9 μg/mL. Analogue 16a possessed antimalarial activity against chloroquine sensitive D6 clone of Plasmodium falciparum. None of the compounds showed toxicity against mammalian kidney fibroblasts (vero cells) upto the concentration of 4.76 μg/ml.
- Bharate, Sandip B.,Bhutani, Kamlesh K.,Khan, Shabana I.,Tekwani, Babu L.,Jacob, Melissa R.,Khan, Ikhlas A.,Singh, Inder Pal
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p. 1750 - 1760
(2007/10/03)
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- An efficient two-step synthesis of jensenone isolated from Eucalyptus jensenii. Synthesis of analogues and evaluation as antioxidants
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A phloroglucinol derivative, jensenone (1) isolated from leaves of Eucalyptus jensenii has been synthesized for the first time through a short and efficient two-step procedure starting from commercially available phloroglucinol. The methodology provides a simplified route to introduce diformyl moiety for synthesis of biologically active formylated phloroglucinol compounds such as antimalarial robustadials, cancer chemopreventive euglobals, and antifouling sideroxylonals. Several analogues of jensenone have also been synthesized and evaluated for antioxidant capacity. CSIRO 2005.
- Bharate, Sandip B.,Chauthe, Siddheshwar K.,Bhutani, Kamlesh K.,Singh, Inder P.
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p. 551 - 555
(2007/10/03)
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- Biological activities of α-mangostin derivatives against acidic sphingomyelinase
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Deprenyl and benzofenone-type congeners of α-mangostin 1 have been synthesized to understand their role for the inhibitory activity against sphingomyelinase (SMase). While removal of the prenyl group of the right side (11 and 12) caused loss of the selectivity between ASMase (acidic sphingomyelinase) and NSMase (neutral sphingomyelinase), the prenyl group of the left side appeared to increase the inhibitory activities (16 and 17).
- Hamada, Motoko,Iikubo, Kazuhiko,Ishikawa, Yuichi,Ikeda, Aya,Umezawa, Kazuo,Nishiyama, Shigeru
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p. 3151 - 3153
(2007/10/03)
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- Metallated 2-alkenyl sulfoximines in asymmetric synthesis: Regio- and stereoselective synthesis of highly substituted oxabicyclic ethers and studies towards the total syntheses of the euglobals G1 and G2 and arenaran A
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2-Cyclopentenyl- and 2-cyclohexenylmethyl sulfoximines can be converted into angular carbon-functionalised, highly substituted, isomerically pure (ds ± 98%) 2-oxabicyclo[3.3.0]octanes and 2-oxabicyclo[3.4.0]nonanes in high yields by a convenient one-pot sequence. Molecular frameworks such as these can be found in many biologically active natural products. In addition to the methodological work, we report on studies towards the total synthesis of the euglobals G1 and G2 and arenaran A.
- Reggelin, Michael,Gerlach, Matthias,Vogt, Melanie
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p. 1011 - 1031
(2007/10/03)
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- Silyl triflate-mediated ring-closure and rearrangement in the synthesis of potential bisfuran-containing intermediates of aflatoxin biosynthesis
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The biosynthetic pathway to the potent mycotoxin aflatoxin B1 is unusually long and complex, proceeding from anthraquinone to xanthone to coumarin nuclear types bearing fused tetrahydro- and bisdihydrofuran rings. A synthetic strategy is described involving two silyl triflate-mediated cyclization and rearrangement processes that have enabled both furofuran oxidation states to be readily achieved and undesired but thermodynamically favorable side reactions to be avoided in the preparation of these ring systems. In the first an o-methoxymethyl phenylacetaldehyde is cyclized directly to the five-membered, differentially protected hemiacetal, while in the second this group, appropriately substituted, can be rearranged to a 4- trialkylsilyloxy-2,5-methano-1,3-benzodioxepane. The latter masked dialdehyde is sufficiently stable to strong base, mild acid, and oxidants to allow all needed aryl ring systems to be constructed. Using these methods, total syntheses of (±)-versicolorin B, (±)-versicolorin A, its hemiacetal, and its 6-deoxy derivative, (±)-6-deoxyversicolorin A, have been achieved, and these are reported herein, as well as preparation of the methyl ester of a putative o-carboxybenzophenone biosynthetic intermediate. In work described elsewhere, incorporation experiments with 13C-labeled forms of these compounds have made possible the complete elucidation of bisfuran biosynthesis characteristic of the first major phase of aflatoxin formation in vivo.
- Graybill, Todd L.,Casillas, Eduard G.,Pal, Kollol,Townsend, Craig A.
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p. 7729 - 7746
(2007/10/03)
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- First total synthesis of (±)-kenusanone b
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The first total synthesis of a natural prenylflavanone, (±)-kenusanone B (1) has been achieved by condensation of acetophenone 4 and benzaldehyde 6 followed by cyclization and deprotection. Chloromethyl methyl ether was used as a facile protecting reagent of free hydroxy groups for the synthesis of polyhydroxylated flavanones.
- Xiao, Li,Tan, Wenfei,Li, Yulin
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p. 2861 - 2869
(2007/10/03)
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- Process for the synthesis of anthocyanidines and novel intermediates produced in said processes
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A novel procedure is provided for producing anthocyanidines by reacting 2,4-di-O-protected derivative phloroglucinaldehyde of formula VII wherein Pg1 and Pg2 each represents an O-protecting group with a compound of formula V wherein in Ar represents optionally substituted aryl and Pg3 represents a O-protecting group. Protecting groups in the resulting condensation product are optionally converted to free hydroxyl groups. The invention further provides a novel method for producing phloroglucinaldehyde derivatives of formula VII as well as a novel procedure for producing phloroglucinaldehyde itself.
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- Ortho Effect in the Fragmentation of 2-Acetoxychalcones under Electron Impact
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2-Acetoxychalcones decompose under electron impact conditions by loss of an acetoxy fragment to form flavylium ions.The effect is restricted to the ortho position and is reduced after hydrogenation of the chalcone double bond.The intense flavylium ion originates as shown by specific labelling with 18O-from two different fragmentation lines: (a) direct loss of an acetoxy radical by cleavage of the phenolic Ar-O bond and (b) sequential elimination of ketene and a hydroxy radical.
- Mentlein, Rolf,Vowinkel, Erich
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p. 330 - 333
(2007/10/02)
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