59684-62-7Relevant academic research and scientific papers
Total Synthesis and Antibiotic Properties of Amino-Functionalized Aromatic Terpenoids Related to Erogorgiaene and the Pseudopterosins
Greven, Tobias,Neud?rfl, J?rg-Martin,Rausch, Marvin,Schmalz, Hans-Günther,Schneider, Tanja,Schumacher, Christian Eric
, (2022/02/23)
Following a concept recently introduced by Hergenrother,[6] the present study addresses the question of whether certain antimicrobially active aromatic (marine) natural products can be converted into more potent broad-spectrum antibiotics by introducing an aminoalkyl side chain. To this end, phenolic mono- and sesquiterpenoids (incl. carvacrol, xanthorrhizol, and 7-hydroxycalamene) as well as the diterpenes 7-hydroxyerogorgiaene and 9-deoxypseudopterosin A were converted into amino-functionalized analogs that display either an amino-methyl or a 2-amino-ethoxy substituent in place of (or next to) the OH group. This was achieved either by Pd-catalyzed nitromethylation/reduction of the aryltriflates, by O-alkylation of the phenols with bromoacetonitrile and subsequent reduction, or by ortho-hydroxymethylation/amination. During the study, an efficient enantioselective total synthesis of 7-hydroxyerogorgiaene (8 steps, 29 % overall yield) and 9-deoxypseudopterosin A (9 steps, 30 % overall yield) was elaborated using an asymmetric cobalt-catalyzed hydrovinylation (91 % ee) of 3-methoxy-4-methyl-styrene as the chirogenic step. Other important C?C bond forming steps include a Pd-catalyzed Suzuki cross-coupling and diastereoselective Lewis acid-mediated cyclization reactions. A total of 16 amino derivatives of natural products were prepared and subsequently tested for their antibacterial properties. Some of the diterpene-derived amines showed high efficacy, not only against Gram-positive (S. aureus SG511, S. aureus HG003, B. subtilis 168; MIC=0.5 to 2 μg/ml), but also against Gram-negative bacterial strains (E. coli K12; E. coli I-11276b; MIC=8 to 32 μg/ml). This clearly supported the underlying working hypothesis.
Preparation of [kisantorizoru[kisantorizoru]
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Paragraph 0076-0078, (2020/09/12)
[Problem] an easy operation, can be obtained in a high yield of high-purity [kisantorizoru[kisantorizoru][kisantorizoru[kisantorizoru] preparation. [Solution] a method for preparing [kisantorizoru[kisantorizoru], amino acids in the presence of a condensation agent in a solvent extract curcuma [kisantoriza[kisantoriza] · stirring, the reaction mixture obtained in the step [kisantorizoruamino[kisantorizoruamino] acid ester, the reaction mixture, a mixture solution was prepared by adding ester-based solvent, the mixture was extracted with water under acidic conditions process, and the water contained in the hydrolyzed ester is extracted [kisantorizoruamino[kisantorizoruamino] extract, [kisantorizoru[kisantorizoru] comprises obtaining, [kisantorizoru[kisantorizoru] preparation. [Drawing] no
Cobalt-Catalyzed Enantioselective Negishi Cross-Coupling of Racemic α-Bromo Esters with Arylzincs
Liu, Feipeng,Zhong, Jiangchun,Zhou, Yun,Gao, Zidong,Walsh, Patrick J.,Wang, Xueyang,Ma, Sijie,Hou, Shicong,Liu, Shangzhong,Wang, Minan,Wang, Min,Bian, Qinghua
supporting information, p. 2059 - 2064 (2018/02/14)
The first cobalt-catalyzed enantioselective Negishi cross-coupling reaction, and the first arylation of α-halo esters with arylzinc halides, are disclosed. Employing a cobalt-bisoxazoline catalyst, various α-arylalkanoic esters were synthesized in excellent enantioselectivities and yields (up to 97 % ee and 98 % yield). A diverse range of functional groups, including ether, halide, thioether, silyl, amine, ester, acetal, amide, olefin and heteroaromatics is tolerated by this method. This method was suitable for gram-scale reactions, enabling the synthesis of (R)-xanthorrhizol with high enantiopurity. Radical clock experiments support the intermediacy of radicals.
Preparation and use of enantioenriched 2-aryl-propylsulfonylbenzene derivatives as valuable building blocks for the enantioselective synthesis of bisabolane sesquiterpenes
Serra, Stefano
, p. 1561 - 1572 (2015/02/05)
We have demonstrated that different enantioenriched 2-arylpropylsufonylbenzene derivatives are very useful building blocks for the synthesis of aromatic bisabolane sesquiterpenes. Their preparation and the exploitation of their chemical reactivity have been comprehensively investigated. Accordingly, the naturally occurring bisabolane sesquiterpenes (-)-curcuphenol, (-)-xanthorrhizol, (+)-glandulone A, (+)-curcudiol, (+)-turmerone and (+)-curcudiol-10-one were synthesized in high enantiomeric purity. It is worth noting that the compounds (+)-curcudiol-10-one and (+)-glandulone A were prepared in enantioenriched form for the first time. Through the proposed synthetic approaches, we were able to confirm both chemical structures and the absolute configurations previously assigned to the two aforementioned sesquiterpenes.
Enantioselective iridium-catalyzed hydrogenation of β,γ- unsaturated carboxylic acids: An efficient approach to chiral 4-alkyl-4-aryl butanoic acids
Song, Song,Zhu, Shou-Fei,Yang, Shuang,Li, Shen,Zhou, Qi-Lin
supporting information; experimental part, p. 2708 - 2711 (2012/04/17)
Chiral acids: A highly enantioselective iridium-catalyzed hydrogenation of β,γ-unsaturated carboxylic acids is developed for the preparation of chiral 4-alkyl-4-aryl butanoic acids (see scheme). Copyright
A short synthesis of bisabolane sesquiterpenes
Du, Zhen-Ting,Zheng, Shuai,Chen, Gang,Lv, Dong
experimental part, p. 8053 - 8061 (2011/11/05)
A facile total synthesis of three members of the bisabolane sesquiterpene family, namely (±)-curcumene, (±)-xanthorrhizol and (±)-curcuhydroquinone had been achieved in high overall yield. The synthesis used bromobenzene derivatives as starting materials.
Efficient total synthesis of racemic bisabolane sesquiterpenes curcuphenol and xanthorrhizol starting from substituted acetophenones
Montiel, Luisa E.,Zepeda, L. Gerardo,Tamariz, Joaquin
experimental part, p. 1261 - 1273 (2010/09/07)
A total synthesis of natural bisabolane sesquiterpenes curcuphenol (1) and xanthorrhizol (2) was developed by using the substituted acetophenones 4 and 5, respectively, as starting materials. The acetyl group of the latter was activated through ethoxycarb
The first enantiospecific synthesis of (-)-heritol: absolute configuration determination
Chavan, Subhash P.,Thakkar, Mahesh,Kalkote, Uttam R.
, p. 643 - 646 (2007/10/03)
The first enantiospecific synthesis of (-)-heritol, from naturally occurring (R)-(+)-citronellal and confirmation of its absolute configuration, is described.
An enantiospecific synthesis of (+)-isoparvifolinone and (-)-parvifoline
Chavan, Subhash P.,Thakkar, Mahesh,Kalkote, Uttam R.
, p. 535 - 537 (2007/10/03)
An enantiospecific synthesis of (+)-isoparvifolinone and (-)-parvifoline, from naturally occurring (R)-(+)-citronellal, employing intramolecular Friedel-Crafts acylation as the key step, is described.
Synthesis of (R)-curcumene and (R)-xanthorrizol based on 1,2-aryl migration via phenonium ion
Ehara, Takeru,Tanikawa, Shin,Ono, Machiko,Akita, Hiroyuki
, p. 1361 - 1364 (2008/03/11)
Solvolysis reaction of methyl (4S,5S)-4-(4′-methoxyphenyl)-5- tosyloxy-2(E)-hexenoate 5 in water-saturated MeNO2 gave the 1,2-migration product, (4S,5S)-5-hydroxy-4-(4′-methoxyphenyl)-2-(E)- hexenoate 6 (55% yield), which was converted to methyl (R)-(4′- methylphenyl)hexanoate 11 in 25% overall yield (5 steps). Treatment of (R)-11 with MeLi gave tertiary alcohol congener 12, which was subjected to dehydration to afford (R)-(-)-curcumene 1. An introduction of hydroxyl group at meta-position of the aromatic ring in (R)-11 was achieved based on consecutive treatment [1) selective iodination, 2) conversion of aryl iodide to aryl boronate, 3) conversion of aryl boronate to phenol]. Thus obtained phenol (R)-16 was treated with MeLi to give tertiary alcohol congener 17, which was subjected to dehydration to afford (R)-(-)-xanthorrizol 2.
