3147-39-5Relevant academic research and scientific papers
Synthesis of xyloketal A, B, C, D, and G analogues
Pettigrew, Jeremy D.,Wilson, Peter D.
, p. 1620 - 1625 (2006)
A series of demethyl analogues of the natural products xyloketal A, B, C, D, and G have been prepared in a notably direct manner from 3-hydroxymethyl-2- methyl-4,5-dihydrofuran and a series of corresponding phenols. These syntheses featured a boron trifluoride diethyl etherate-promoted electrophilic aromatic substitution reaction as a key step. In the case of the synthesis of analogues of xyloketal A, the process was found to be highly efficient (up to 93% yield). The optimized isolated yield of these reaction products is remarkable in view of the fact that this transformation involves, minimally, six individual reactions. Moreover, these synthetic studies provide significant insight into the possible biogenic origin of the xyloketal natural products.
Novel diphenylmethyl compounds having mycobacterium tuberculosis inhibitory activity
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Paragraph 0525-0528, (2019/02/13)
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.
Biocatalytic Properties and Structural Analysis of Phloroglucinol Reductases
Conradt, David,Hermann, Bianca,Gerhardt, Stefan,Einsle, Oliver,Müller, Michael
supporting information, p. 15531 - 15534 (2016/12/09)
Phloroglucinol reductases (PGRs) are involved in anaerobic degradation in bacteria, in which they catalyze the dearomatization of phloroglucinol into dihydrophloroglucinol. We identified three PGRs, from different bacterial species, that are members of the family of NAD(P)H-dependent short-chain dehydrogenases/reductases (SDRs). In addition to catalyzing the reduction of the physiological substrate, the three enzymes exhibit activity towards 2,4,6-trihydroxybenzaldehyde, 2,4,6-trihydroxyacetophenone, and methyl 2,4,6-trihydroxybenzoate. Structural elucidation of PGRcl and comparison to known SDRs revealed a high degree of conservation. Several amino acid positions were identified as being conserved within the PGR subfamily and might be involved in substrate differentiation. The results enable the enzymatic dearomatization of monoaromatic phenol derivatives and provide insight into the functional diversity that may be found in families of enzymes displaying a high degree of structural homology.
Synthesis and antihyperglycemic activity of phenolic C-glycosides
Rawat, Preeti,Kumar, Manmeet,Rahuja, Neha,Srivastava, Daya Shankar Lal,Srivastava, Arvind Kumar,Maurya, Rakesh
scheme or table, p. 228 - 233 (2011/02/27)
Various phenolic C-glycosides were evaluated for their in vitro and in vivo antihyperglycemic activity employing glucose uptake by rat muscle cell lines (L-6) and low dosed-streptozotocin-induced diabetic rats, respectively. Some of phenolic C-glycosides were isolated from Pterocarpus marsupium and Ulmus wallichiana and other were synthesized by unprotected sugar and phloroacetophenone using Sc(OTf)3 in aqueous ethanol. Eight among tested compounds showed significant lowering of blood glucose level on low dosed-streptozotocin-induced diabetic rats. The compound 24 lowered the blood glucose levels by 34.9% and 33.6% during 0-5 h and 0-24 h, respectively, at the dose of 25 mg/kg body weight which is comparable to standard antidiabetic drug metformin.
Synthesis and fate of o-carboxybenzophenones in the biosynthesis of aflatoxin
Henry, Kevin M.,Townsend, Craig A.
, p. 3300 - 3309 (2007/10/03)
o-Carboxybenzophenones have long been postulated to be intermediates in the oxidative rearrangement of anthraquinone natural products to xanthones in vivo. Many of these Baeyer-Villiger-like cleavages are believed to be carried out by cytochrome P450 enzymes. In the biosynthesis of the fungal carcinogen, aflatoxin, six cytochromes P450 are encoded by the biosynthetic gene cluster. One of these, AflN, is known to be involved in the conversion of the anthraquinone versicolorin A (3) to the xanthone demethylsterigmatocystin (5) en route to the mycotoxin. An aryl deoxygenation, however, also takes place in this overall transformation and is proposed to be due to the requirement that an NADPH-dependent oxidoreductase, AflM, be active for this process to take place. What is known about other fungal anthraquinone → xanthone conversions is reviewed, notably, the role of the o-carboxybenzophenone sulochrin (25) in geodin (26) biosynthesis. On the basis of mutagenesis experiments in the aflatoxin pathway and these biochemical precedents, total syntheses of a tetrahydroxy-o-carboxybenzophenone bearing a fused tetrahydrobisfuran and its 15-deoxy homologue are described. The key steps of the syntheses entail rearrangement of a 1,2-disubstituted alkene bearing an electron-rich benzene ring under Kikuchi conditions to give the 2-aryl aldehyde 43 followed by silyltriflate closure to a differentially protected dihydrobenzofuran 44. Regiospecific bromination, conversion to the substituted benzoic acid, and condensation with an o-bromobenzyl alcohol gave esters 47 and 50. The latter could be rearranged with strong base, oxidized, and deprotected to the desired o-carboxybenzophenones. These potential biosynthetic intermediates were examined in whole-cell and ground-cell experiments for their ability to support aflatoxin formation in the blocked mutant DIS-1, defective in its ability to synthesize the first intermediate in the pathway, norsolorinic acid. Against expectation, neither of these compounds was converted into aflatoxin under conditions where the anthraquinones versicolorin A and B readily afforded aflatoxins B1 and B2. This outcome is evaluated further in a companion paper appearing later in this journal.
Chemistry of 1,3,5-Tris(trimethylsiloxy)-1-methoxyhexa-1,3,5-triene, a β-Tricarbonyl Trianion Equivalent
Chan, T. H.,Stoessel, D.
, p. 2423 - 2428 (2007/10/02)
The title compound has been synthesized and its chemistry studied.Condensation with orthoesters, acid chlorides, or imidazolides gave aromatic compounds in a 5C + 1C condensation.A formal synthesis of lasiodiplodin has been completed.
Boron Trichloride as a Selective Demethylating Agent for Hindered Ethers: a Synthesis of the Phytoalexins α- and β-Pyrufuran, a Synthesis of Tri-O-methylleprolomin and its Demethylation
Carvalho, Christopher F.,Russo, Albert V.,Sargent, Melvyn V.
, p. 777 - 792 (2007/10/02)
Boron trichloride has been found to be an efficient reagent for the selective cleavage of sterically hindered methoxy groups in methoxyarenes.The scope and utility of this reaction are explored with examples drawn from derivatives of benzene, naphtalene, 9,10-dihydrophenanthrene and dibenzofuran.The method is applied to the synthesis of the phytoalexins α- (56) and β-pyrofuran (58) (1,3,4-trimethoxydibenzofuran-2-ol and 1,2,4-trimethoxydibenzofuran-3-ol).A synthesis of tri-O-methylleprolomin (61), a derivative of the unusual lichen metabolite leprolomin (60), is described and its demethylation with boron trichloride is studied.
