56724-03-9Relevant academic research and scientific papers
Vanadium-Catalyzed Oxidative Intramolecular Coupling of Tethered Phenols: Formation of Phenol-Dienone Products
Gilmartin, Philip H.,Kozlowski, Marisa C.
, p. 2914 - 2919 (2020/04/10)
A mild and efficient method for the vanadium-catalyzed intramolecular coupling of tethered free phenols is described. The corresponding phenol-dienone products are prepared directly in good yields with low catalyst loadings. Electronically diverse tethered phenol precursors are well tolerated, and the catalytic method was effectively applied as the key step in syntheses of three natural products and a synthetically useful morphinan alkaloid precursor.
4-benzylaminobenzenesulfonamide derivative and preparation and application thereof
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, (2020/08/30)
The invention provides a 4-benzylaminobenzenesulfonamide derivative represented by a formula (I) or a pharmaceutically acceptable salt, a solvate or a metabolite thereof. In the formula (I), R1, R2, R3, R4, R5 and R6 are defined in the specification. The
Hydrazide-Catalyzed Polyene Cyclization: Asymmetric Organocatalytic Synthesis of cis-Decalins
Plamondon, Samuel J.,Warnica, Josephine M.,Kaldre, Dainis,Gleason, James L.
supporting information, p. 253 - 258 (2019/11/28)
Polyene cyclizations offer rapid entry into terpenoid ring systems. Although enantioselective cyclizations of (E)-polyenes to form trans-decalin ring systems are well precedented, highly enantioselective cyclizations of (Z)-polyenes to form the correspond
Volatiles from the xylarialean fungus Hypoxylon invadens
Dickschat, Jeroen S.,Wang, Tao,Stadler, Marc
, p. 734 - 746 (2018/04/16)
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.
Chemoselective Reduction of Sterically Demanding N,N-Diisopropylamides to Aldehydes
Xiao, Peihong,Tang, Zhixing,Wang, Kai,Chen, Hua,Guo, Qianyou,Chu, Yang,Gao, Lu,Song, Zhenlei
, p. 1687 - 1700 (2018/02/23)
A sequential one-pot process for chemoselectively reducing sterically demanding N,N-diisopropylamides to aldehydes has been developed. In this reaction, amides are activated with EtOTf to form imidates, which are reduced with LiAlH(OR)3 [R = t-Bu, Et] to give aldehydes by hydrolysis of the resulting hemiaminals. The non-nucleophilic base 2,6-DTBMP remarkably improves reaction efficiency. The combination of EtOTf/2,6-DTBMP and LiAlH(O-t-Bu)3 was found to be optimal for reducing alkyl, alkenyl, alkynyl, and 2-monosubstituted aryl N,N-diisopropylamides. In contrast, EtOTf and LiAlH(OEt)3 in the absence of base were found to be optimal for reducing extremely sterically demanding 2,6-disubstituted N,N-diisopropylbenzamides. The reaction tolerates various reducible functional groups, including aldehyde and ketone. 1H NMR studies confirmed the formation of imidates stable in water. The synthetic usefulness of this methodology was demonstrated with N,N-diisopropylamide-directed ortho-metalation and C-H bond activation.
α-Ketocarbenium Ions Derived from Orthoquinone-Containing Polycyclic Aromatic Compounds
Urakawa, Kazuki,Kawabata, Yuta,Matsuda, Masaki,Sumimoto, Michinori,Ishikawa, Hayato
, p. 2534 - 2537 (2018/05/22)
α-Ketocarbenium ions derived from synthesized orthoquinone-containing polycyclic aromatic compounds were generated in the presence of Br?nsted acids such as sulfuric acid, trifluoromethanesulfonic acid, and fluorosulfonic acid. The prepared α-ketocarbeniu
TRICYCLIC PIPERIDINE COMPOUNDS
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Page/Page column 88, (2016/11/21)
The present invention relates to compounds of the formula (I) wherein R1a, R1b, R2, R3, (R4)n and ring (A) are as described in the description, to their preparation, to pharmaceutically acc
Structural interrogation of benzosuberene-based inhibitors of tubulin polymerization
Herdman, Christine A.,Devkota, Laxman,Lin, Chen-Ming,Niu, Haichan,Strecker, Tracy E.,Lopez, Ramona,Liu, Li,George, Clinton S.,Tanpure, Rajendra P.,Hamel, Ernest,Chaplin, David J.,Mason, Ralph P.,Trawick, Mary Lynn,Pinney, Kevin G.
, p. 7497 - 7520 (2015/12/18)
The discovery of 3-methoxy-9-(3′,4′,5′-trimethoxyphenyl)-6,7-dihydro-5H-benzo[7]annulen-4-ol (a benzosuberene-based analogue referred to as KGP18) was originally inspired by the natural products colchicine and combretastatin A-4 (CA4). The relative struct
Inverting the regioselectivity of the berberine bridge enzyme by employing customized fluorine-containing substrates
Resch, Verena,Lechner, Horst,Schrittwieser, Joerg H.,Wallner, Silvia,Gruber, Karl,MacHeroux, Peter,Kroutil, Wolfgang
supporting information, p. 13173 - 13179 (2013/01/15)
Fluorine is commonly applied in pharmaceuticals to block the degradation of bioactive compounds at a specific site of the molecule. Blocking of the reaction center of the enzyme-catalyzed ring closure of 1,2,3,4- tetrahydrobenzylisoquinolines by a fluoro moiety allowed redirecting the berberine bridge enzyme (BBE)-catalyzed transformation of these compounds to give the formation of an alternative regioisomeric product namely 11-hydroxy-functionalized tetrahydroprotoberberines instead of the commonly formed 9-hydroxy-functionalized products. Alternative strategies to change the regioselectivity of the enzyme, such as protein engineering, were not applicable in this special case due to missing substrate-enzyme interactions. Medium engineering, as another possible strategy, had clear influence on the regioselectivity of the reaction pathway, but did not lead to perfect selectivity. Thus, only substrate tuning by introducing a fluoro moiety at one potential reactive carbon center switched the reaction to the formation of exclusively one regioisomer with perfect enantioselectivity. Custom-made substrates: Employing customized substrates with a fluoro atom at the normally preferred reaction site switched the regioselectivity of the berberine-bridged enzyme. With this strategy, it was possible to get access to (S)-11-hydroxy-functionalized berbines in an asymmetric fashion by using the wild-type enzyme (see scheme). Copyright
Dihydrospiro[dibenzo[a,d][7]annulene-5,4'-imidazol] compounds for the inhibition of beta-secretase
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Page/Page column 8, (2008/06/13)
The present invention provides a 10,11-dihydrospiro[dibenzo[a,d][7]annulene-5,4′-imidazol]-5′(1′H)-one compound of formula I Also provided are methods and compositions for the inhibition of β-secretase (BACE) and the treatment of β-amyloid deposits and neurofibrillary tangles.
