- Selective Electrochemical Oxygenation of Alkylarenes to Carbonyls
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An efficient electrochemical method for benzylic C(sp3)-H bond oxidation has been developed. A variety of methylarenes, methylheteroarenes, and benzylic (hetero)methylenes could be converted into the desired aryl aldehydes and aryl ketones in moderate to excellent yields in an undivided cell, using O2 as the oxygen source and lutidinium perchlorate as an electrolyte. On the basis of cyclic voltammetry studies, 18O labeling experiments, and radical trapping experiments, a possible single-electron transfer mechanism has been proposed for the electrooxidation reaction.
- Li, Xue,Bai, Fang,Liu, Chaogan,Ma, Xiaowei,Gu, Chengzhi,Dai, Bin
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supporting information
p. 7445 - 7449
(2021/10/02)
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- Total synthesis of the proposed structure of Anti-TMV active tabasesquiterpene A
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The proposed structure of Tabasesquiterpene A, an illudalane type of sesquiterpene has been synthesized in twelve steps from 2-methoxy-4-methylbenzaldehyde in 40% overall yield. Triflic acid mediated intramolecular Freidel-Crafts acylation allows to develop the critical indanone moiety, a key intermediate of this synthesis. A careful ortho-selective formylation and subsequent Knoevenagel condensation to incorporate three carbon side chain, followed by reduction, formation of tricyclic lactone and DIBAL-H supported reduction of lactone to target were other key transformation involved. The NMR spectroscopic data of the synthetic sample differ from those of natural tabasesquiterpene A.
- Kumari, Anusueya,Suresh, Muthiah,Singh, Raj Bahadur
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- Volatiles from the xylarialean fungus Hypoxylon invadens
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The volatiles emitted by agar plate cultures of the xylarialean fungus Hypoxylon invadens were investigated by use of a closed loop stripping apparatus in combination with GC-MS. Several aromatic compounds were found that could only be identified by comparison to all possible constitutional isomers with different ring substitution patterns. For the set of identified compounds a plausible biosynthetic scheme was suggested that gives further support for the assigned structures.
- Dickschat, Jeroen S.,Wang, Tao,Stadler, Marc
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p. 734 - 746
(2018/04/16)
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- The Wender Cedrene Synthesis Revisited: A Catalytic Enantioselective Entry to the Chiral Key Intermediate
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The seminal synthesis of the sesquiterpene (±)-α-cedrene reported by Wender in 1981 offers a uniquely short and elegant access to the bridged-tricyclic target compound by exploiting an intramolecular arene-olefin photocycloaddition. However, the synthesis was performed only in the racemic series so far. This synthesis was now re-investigated and the catalytic methods for the enantioselective preparation of the chiral key intermediate were evaluated. It was found that Cu-catalyzed allylic substitution of a cinnamyl chloride with MeMgBr in the presence of a Taddol-derived chiral phosphine-phosphite ligand affords the corresponding (1-methylallyl)arene with high enantioselectivity (94% ee). Hydroboration and subsequent Suzuki coupling gave (R)-curcuphenol methyl ether from which (-)-α-cedrene was prepared along the route paved by Wender.
- Westphal, Julia,Schumacher, Christian Eric,Schmalz, Hans-Günther
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- 2-BENZYL-BENZIMIDAZOLE COMPLEMENT FACTOR B INHIBITORS AND USES THEREOF
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The present invention provides a compound of formula (I) a method for manufacturing the compounds of the invention, and its therapeutic uses. The present invention further provides a combination of pharmacologically active agents and a pharmaceutical comp
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Page/Page column 47
(2015/05/19)
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- Modulation on C- and N-terminal moieties of a series of potent and selective linear tachykinin NK2 receptor antagonists
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Herein we describe the synthesis of a series of new potent tachykinin NK2 receptor antagonists by the modulation of the Cand N-terminal moieties of ibodutant (MEN 15596, 1). The Nterminal benzo[b]thiophene ring was replaced by different substituted naphthalenes and benzofurans, while further modifications were evaluated at the C-terminal tetrahydropyran moiety. Most compounds demonstrated a high affinity for the human NK2 receptor and high in vitro antagonist potency, indicating that a wide range of substituents at both termini can be incorporated in the molecule without detrimental effects on the interactions with the NK2 receptor. Selected compounds were tested in vivo confirming their activity as NK2 antagonists. In particular, after both iv and id administration to guinea pig, compound 61b was able to antagonize NK2-induced colonic contractions with a potency and duration-of-action fully comparable to the reference compound 1 (MEN 15596, ibodutant).
- Gensini, Martina,Altamura, Maria,Dimoulas, Tula,Fedi, Valentina,Giannotti, Danilo,Giuliani, Sandro,Guidi, Antonio,Harmat, Nicholas J. S.,Meini, Stefania,Nannicini, Rossano,Pasqui, Franco,Tramontana, Manuela,Triolo, Antonio,Maggi, Carlo Alberto
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experimental part
p. 65 - 78
(2010/11/16)
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- Binding of Phenylalkylamine Derivatives at 5-HT1C and 5-HT2 Serotonin Receptors: Evidence for a Lack of Selectivity
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Certain phenyalkylamine derivatives have been considered to bind selectively at 5-HT2 serotonin receptors.It is now recognized that the most widely used derivatives, i.e., 1-(2,5-dimethoxy-4-X-phenyl)-2-aminopropanes where X = Me (DOM), Br (DOB), and I (DOI) (1-3, respectively) also bind at the more recently identified population of serotonin 5-HT1C receptors.The purpose of the present investigation was to determine whether simple phenylalkylamines bind selectively at one population of receptors over the other.An examination of 34 derivatives reveals (i) similar structure-affinity relationships and (ii) a significant correlation (r = >0.9, n = 25) between 5-HT1C and 5-HT2 affinity.None of the compounds included in the present study displayed more than a 10-fold selectivity for one population of these receptors over the other; the results suggest that these compounds (including the widely used 5-HT2 agonists DOB and DOI) are 5-HT1C/5-HT2 agents.
- Glennon, Richard A.,Raghupathi, Reva,Bartyzel, Piotr,Teitler, Milt,Leonhardt, Sigrun
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p. 734 - 740
(2007/10/02)
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- Regiospecific Oxidation of Methyl Groups in Dimethylanisoles
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Dimethylanisoles in which one of the methyl groups is meta and the other is ortho or para are regiospecifically oxidized in high yield to the corresponding ortho- and para-substituted aldehydes by copper(II) and peroxydisulfate.Subsequent oxidation of the
- Hauser, Frank M.,Ellenberger, Suzanne R.
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p. 723 - 724
(2007/10/02)
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